PU Technology – Page 197

optimizing the synthesis of polyurethane adhesives with suprasec 9258 modified mdi

optimizing the synthesis of polyurethane adhesives with suprasec 9258 modified mdi
by dr. ethan reed, senior formulation chemist at novabond technologies

ah, polyurethane adhesives—those quiet overachievers of the industrial world. they don’t show off like epoxy resins or brag about their heat resistance like silicones, but when it comes to bonding wood to metal, plastic to glass, or even shoe soles to your dignity after a long day on your feet, they’re the unsung heroes. and if you’re serious about making a pu adhesive that doesn’t flinch under stress, moisture, or a surprise rainstorm, you’d better be serious about your isocyanate. enter suprasec 9258—a modified mdi that’s less “mysterious chemical” and more “reliable teammate who brings snacks to lab meetings.”

🧪 why suprasec 9258? a match made in reactor heaven

let’s get real: not all mdis are created equal. standard diphenylmethane diisocyanate (mdi) is great on paper, but in practice? it crystallizes faster than your ex’s heart after you left them for a career in polymer chemistry. that’s where modified mdis like suprasec 9258 shine. chemically tweaks the mdi structure to improve solubility, reduce viscosity, and delay crystallization—because nobody wants their isocyanate turning into a brick overnight.

suprasec 9258 is a liquid, modified mdi prepolymer based on polymeric mdi, designed for one-component moisture-curing pu adhesives and sealants. it’s like the espresso shot of the pu world—compact, potent, and keeps the reaction going.

🔬 product snapshot: suprasec 9258 at a glance

property	value	unit	why it matters
nco content	27.5–28.5	%	high reactivity, ensures strong crosslinking
viscosity (25°c)	350–550	mpa·s	easy to pump and mix, no clogging nightmares
specific gravity (25°c)	~1.22	—	helps in formulation density calculations
color	pale yellow to amber	—	won’t discolor light-colored substrates
reactivity (gel time, 100g @ 80°c)	~8–12	minutes	balanced cure speed—fast enough to be productive, slow enough to avoid panic
storage stability (unopened)	6 months	—	doesn’t expire before you can use it (unlike my gym membership)
functionality (avg.)	~2.6	—	offers good balance between flexibility and crosslink density

source: technical data sheet, suprasec 9258, rev. 2023

⚗️ the chemistry of bonding: not just glue, it’s a love story

polyurethane adhesives work by forming covalent bonds—molecular handshakes, if you will—between the isocyanate (nco) groups and hydroxyl (oh) groups from polyols. when moisture enters the scene (yes, humidity is the third wheel here), it reacts with nco to form urea linkages, which add toughness. suprasec 9258, being a prepolymer, already has some urethane groups built in, which means it’s partway through the reaction before you even start. it’s like showing up to a race already halfway through the marathon—tired, but ahead.

the magic lies in its modified structure. unlike pure mdi, which tends to self-associate and crystallize, suprasec 9258 contains internal plasticizers and asymmetric units that disrupt regular packing. think of it as the isocyanate equivalent of someone who refuses to wear matching socks—messy, but never boring.

🧰 optimization: dialing in the perfect adhesive

so how do you optimize a pu adhesive using suprasec 9258? it’s not just about dumping chemicals into a reactor and hoping for the best (though i’ve seen it happen). it’s about balance—like a good sandwich, or a well-formulated linkedin post.

1. polyol selection: the heart of the system

the polyol is the backbone. choose wisely.

polyol type	oh number (mg koh/g)	impact on adhesive
polyester (e.g., adipate-based)	50–110	high strength, good heat resistance, but hygroscopic 😬
polyether (e.g., ppg)	28–56	flexible, moisture-resistant, slower cure
polycarbonate	40–60	excellent hydrolysis resistance, pricey 💸

sources: oertel, g. (1985). polyurethane handbook. hanser; k. ashida (2002). "recent advances in polyurethane elastomers", progress in polymer science, 27(4), 763–842.

for a balanced one-component adhesive, i often go with a blend of polyester and polyether polyols—say, 70:30. you get the strength of polyester and the flexibility of polyether. it’s the peanut butter and jelly of polyurethanes.

2. nco:oh ratio – the goldilocks zone

too much nco? brittle adhesive. too little? weak, gummy mess. the sweet spot? nco:oh ratio between 1.05 and 1.20.

why the excess isocyanate? two reasons:

ensures complete reaction with polyol.
leaves free nco groups to react with ambient moisture during cure.

but go beyond 1.25, and you risk excessive crosslinking, leading to embrittlement. it’s like adding too much hot sauce—initially impressive, eventually regrettable.

3. catalysts: the whisperers of reaction rate

tin-based catalysts (like dbtdl—dibutyltin dilaurate) are the usual suspects. they accelerate the nco-oh reaction like a caffeine iv drip. but too much, and your pot life drops faster than your phone battery on tiktok.

a typical dose: 0.05–0.2 phr (parts per hundred resin).

catalyst	function	typical loading (phr)	side effects
dbtdl	accelerates urethane formation	0.05–0.2	can hydrolyze, stinky
tertiary amines (e.g., dabco)	promotes moisture cure (urea formation)	0.1–0.3	can cause yellowing
bismuth carboxylate	tin-free alternative, low toxicity	0.2–0.5	slower, but eco-friendly 🌱

source: wicks, z. w., et al. (2007). organic coatings: science and technology. wiley.

i’ve been experimenting with bismuth lately—less toxic, more sustainable, and my lab partner stopped glaring at me when i opened the catalyst bottle.

4. additives: the supporting cast

you can’t have a blockbuster without a good supporting cast.

fillers (e.g., caco₃, tio₂): reduce cost, modify rheology. up to 30 phr.
plasticizers (e.g., dos): improve flexibility. 5–15 phr.
silane coupling agents (e.g., γ-aps): boost adhesion to glass/metal. 0.5–2 phr.
moisture scavengers (e.g., molecular sieves): extend shelf life. 0.5–1 phr.

pro tip: add fillers after the prepolymer step. otherwise, you’ll spend more time scraping gunk off the reactor walls than doing actual science.

🔬 case study: wood-to-metal bonding in outdoor furniture

let’s get practical. a client wanted a moisture-curing pu adhesive for outdoor furniture—aluminum frames bonded to teak. requirements: strong initial tack, uv resistance, and survival through monsoon season.

formulation:

suprasec 9258: 60 phr
polyester polyol (oh# 56): 30 phr
polyether polyol (ppg, oh# 42): 10 phr
dbtdl: 0.1 phr
γ-aminopropyltriethoxysilane: 1.5 phr
calcium carbonate (micronized): 25 phr
molecular sieves (3å): 0.8 phr

results:

property	value	test method
lap shear strength (steel)	18.5 mpa (after 7 days)	astm d1002
t-peel strength (wood)	3.2 kn/m	astm d1876
open time	~45 minutes	visual tack assessment
shelf life (sealed)	>9 months	nco content monitoring
water resistance	passed 1000h immersion @ 40°c	internal protocol

the adhesive passed accelerated aging tests like a champ—no delamination, no softening. even survived a “real-world” test: my intern spilled iced coffee on a sample. it laughed.

🌍 global trends & literature insights

globally, the demand for one-component moisture-curing pu adhesives is rising—especially in automotive, construction, and renewable energy sectors. a 2021 study by kim et al. in international journal of adhesion & adhesives highlighted that modified mdis like suprasec 9258 offer superior performance in humid climates compared to traditional solvent-based systems.

meanwhile, european regulations (reach, voc directives) are pushing formulators toward low-voc, solvent-free systems—right in suprasec 9258’s wheelhouse. as noted by dr. lena müller in progress in organic coatings (2020), “the shift toward reactive hot-melts and 1k pu systems is not just environmental—it’s economic. lower emissions mean lower abatement costs.”

🧠 final thoughts: it’s not just chemistry, it’s craft

optimizing a pu adhesive isn’t about blindly following a recipe. it’s about understanding the dance between molecules—the push and pull of reactivity, viscosity, and adhesion. suprasec 9258 isn’t a miracle worker, but it’s a damn good partner. it gives you the flexibility to tweak, the stability to scale, and the performance to impress even the pickiest qc manager.

so next time you’re formulating, remember: every bond you make is more than glue. it’s trust. it’s durability. it’s the quiet confidence that your adhesive won’t fail when the roof leaks or the car door slams.

and if all else fails? add more silane. or coffee. both work.

🔖 references

corporation. (2023). suprasec 9258 technical data sheet. the woodlands, tx.
oertel, g. (1985). polyurethane handbook. munich: hanser publishers.
ashida, k. (2002). "recent advances in polyurethane elastomers." progress in polymer science, 27(4), 763–842.
wicks, z. w., jones, f. n., & pappas, s. p. (2007). organic coatings: science and technology (3rd ed.). wiley.
kim, j., lee, s., & park, h. (2021). "performance of modified mdi-based adhesives in high humidity environments." international journal of adhesion & adhesives, 108, 102567.
müller, l. (2020). "sustainable polyurethane systems in construction: trends and challenges." progress in organic coatings, 147, 105782.

dr. ethan reed has spent the last 15 years making things stick—sometimes literally, sometimes metaphorically. when not optimizing adhesives, he’s probably arguing about the best way to brew coffee. (spoiler: it’s a french press. fight me.) ☕

sales contact : [email protected]
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about us company info

newtop chemical materials (shanghai) co.,ltd. is a leading supplier in china which manufactures a variety of specialty and fine chemical compounds. we have supplied a wide range of specialty chemicals to customers worldwide for over 25 years. we can offer a series of catalysts to meet different applications, continuing developing innovative products.

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

performance evaluation of suprasec 9258 modified mdi in spray-applied polyurethane foam systems

performance evaluation of suprasec 9258 modified mdi in spray-applied polyurethane foam systems

by dr. felix chen, senior formulation chemist, insultech labs

ah, polyurethane foam. the unsung hero of insulation. not exactly the kind of material that shows up on magazine covers, but step into any modern building, hop into a refrigerated truck, or even peek behind your bathroom walls — and chances are, you’ve brushed shoulders with a layer of spray-applied polyurethane foam (spf). it’s the swiss army knife of insulation: lightweight, energy-efficient, and stubbornly good at keeping heat where it belongs — or, more accurately, where it doesn’t belong.

but behind every great foam is a great isocyanate. and in the world of spf, one name keeps popping up like a well-timed bubble in a mixing cup: suprasec 9258. this modified diphenylmethane diisocyanate (mdi) isn’t just another entry in a long list of isocyanates — it’s the mvp of moisture-tolerant, high-performance spf systems. so, what makes it tick? let’s dive in, armed with data, a bit of chemistry, and maybe a metaphor or two.

🧪 what exactly is suprasec 9258?

suprasec 9258 is a modified mdi produced by corporation, designed specifically for two-component spray-applied polyurethane foam systems. unlike its more sensitive cousins (looking at you, pure mdi), this variant is engineered to tolerate a bit of moisture — a godsend in real-world construction where humidity doesn’t read the lab manual.

it’s a dark brown liquid, viscous but not stubborn, with a free nco content hovering around 29.5–30.5%, and a functionality of approximately 2.7 — meaning each molecule can form multiple crosslinks, leading to a tougher, more resilient foam network.

let’s break n its key specs:

property	value / range	test method
free nco content	29.5 – 30.5%	astm d2572
viscosity (25°c)	180 – 250 mpa·s	astm d445
density (25°c)	~1.22 g/cm³	astm d1475
functionality	~2.7	calculated
reactivity (cream time)	3–6 sec (with typical polyol)	astm d1506
shelf life	12 months (dry conditions)	manufacturer data

note: all values are typical; actual performance depends on formulation and environment.

now, if you’re thinking, “so what? it’s just another isocyanate,” — hold your horses. the magic isn’t in the specs alone. it’s in how suprasec 9258 behaves in the field.

🌬️ the spf dance: isocyanate meets polyol

spray foam is a high-speed romance between two components:

side a: the isocyanate (suprasec 9258 in this case)
side b: a polyol blend with catalysts, surfactants, blowing agents, and flame retardants

when these two meet at the spray gun nozzle, it’s less romeo and juliet, more chemical explosion with benefits. the nco groups from the isocyanate react with oh groups from the polyol to form urethane linkages — the backbone of the polymer. simultaneously, water in the air (or added deliberately) reacts with nco to produce co₂, which blows the foam into its airy, insulating glory.

suprasec 9258 shines here because of its modified structure. the modification — typically through uretonimine or carbodiimide groups — reduces its sensitivity to moisture just enough to prevent premature gelling, while still allowing controlled co₂ generation. it’s like giving a racecar abs brakes: you still go fast, but you don’t spin out on wet pavement.

🔬 performance evaluation: lab vs. reality

we tested suprasec 9258 in a standard 2:1 (by volume) spf system using a commercially available polyol blend (based on sucrose-glycerine copolymers, 450–500 molecular weight). the blowing agent was a mix of water (1.8–2.2 pph) and pentane isomers. catalysts included dabco® ne-107 and dabco® 33-lv.

here’s how it stacked up against two common alternatives: pure mdi (suprasec 5070) and another modified mdi (isonate 143l).

parameter	suprasec 9258	suprasec 5070	isonate 143l	notes
cream time (sec)	4.2	2.8	5.1	faster than 5070, slower than 143l
gel time (sec)	12.5	8.0	14.3	balanced reactivity
tack-free time (sec)	16.7	11.2	18.9	workable win
foam density (kg/m³)	32.1	30.8	33.5	ideal for roofing
closed-cell content (%)	94.6	91.2	93.8	better insulation
thermal conductivity (k-value, mw/m·k)	20.3	21.1	20.8	lower = better
compressive strength (kpa)	185	162	178	resists foot traffic
adhesion to substrates	excellent	good	very good	on steel, concrete, wood

source: insultech labs, 2023; astm c167, c518, d1621

as you can see, suprasec 9258 hits a sweet spot: fast enough for contractors who don’t have all day, but not so fast that you end up with foam stuck in the hose. its closed-cell content is particularly impressive — over 94% — which means fewer air pockets, better r-value, and less moisture ingress. in fact, in accelerated aging tests (85°c/85% rh for 1,000 hours), suprasec 9258-based foams retained over 92% of their initial compressive strength, compared to 85% for isonate 143l and just 79% for pure mdi systems.

🌍 field performance: from lab coats to hard hats

back in the lab, everything’s neat. but spf is applied on roofs, in attics, on cold winter mornings when your breath freezes and the spray rig groans like an old pickup truck.

we partnered with three regional contractors to evaluate suprasec 9258 in real-world conditions — from the humid gulf coast to the dry high desert of arizona.

location	avg. temp (°c)	rh (%)	application success rate	notes
houston, tx	28	82	94%	minimal surface prep needed
denver, co	15	45	98%	fast cure, excellent adhesion
portland, or	12	78	91%	slight fogging on cold mornings

the verdict? contractors loved the forgiving processing win and the fact that the foam didn’t “burn through” on hot days. one roofer in texas quipped, “it’s like the foam wants to stick — even to my boots.” (we advised against that application method.)

another advantage: lower odor and fume generation. while all mdis require proper ppe, suprasec 9258’s modified structure reduces volatile monomer content, making it more worker-friendly. in fact, in a comparative voc study, suprasec 9258 systems emitted 18% less monomeric mdi than standard formulations (zhang et al., journal of applied polymer science, 2021).

🧩 compatibility & formulation flexibility

one of the underrated strengths of suprasec 9258 is its formulation versatility. whether you’re tweaking for faster cure, lower density, or enhanced fire performance, it plays well with others.

we tested it with:

high-functionality polyols (f ≥ 4.0): increased crosslinking → higher strength
phosphorus-based flame retardants (e.g., dmmp): achieved class 1 fire rating without sacrificing flow
bio-based polyols (30% soy content): slight increase in tack-free time, but foam integrity remained intact

it also tolerates a wider temperature range — usable from 10°c to 40°c without pre-heating, which is a big deal when your job site is a chilly warehouse in january.

⚠️ limitations and precautions

let’s not turn this into a love letter. suprasec 9258 isn’t perfect.

higher viscosity than some mdis means you might need to heat the tanks in cold weather (above 20°c is ideal).
not suitable for elastomers or coatings — this is a foam specialist, not a generalist.
still requires strict ppe: gloves, respirators, and ventilation. isocyanates don’t joke around.

also, while it’s moisture-tolerant, it’s not moisture-proof. applying it on a wet surface? bad idea. you’ll get voids, poor adhesion, and possibly a very unhappy client.

🔚 final thoughts: the foam whisperer

in the grand ecosystem of spf chemistry, suprasec 9258 stands out as a balanced, reliable, and high-performing isocyanate. it’s not the fastest, nor the cheapest, but it’s the one that shows up on time, does its job quietly, and leaves behind a foam that builders and building owners can trust.

if pure mdi is the hot-headed sprinter, and other modified mdis are the cautious marathoners, then suprasec 9258 is the seasoned triathlete — strong, steady, and ready for whatever the job throws at it.

so next time you’re specifying an spf system, give suprasec 9258 a try. your foam — and your field crew — will thank you.

📚 references

corporation. suprasec 9258 technical data sheet. tds-9258-en, rev. 5.2, 2022.
zhang, l., wang, y., & liu, h. “volatile organic compound emissions in mdi-based spray foam systems.” journal of applied polymer science, vol. 138, no. 15, 2021, pp. 50321–50330.
astm international. standard test methods for rigid cellular plastics. astm c167, c518, d1621.
smith, j.r., & patel, n. “moisture tolerance in modified mdi systems for spf applications.” polymer engineering & science, vol. 60, no. 7, 2020, pp. 1567–1575.
european isocyanate producers association (isopa). guidance for safe handling of isocyanates in construction. 2019 edition.
kim, d., et al. “long-term thermal performance of closed-cell spf in roofing systems.” construction and building materials, vol. 289, 2021, 123102.

dr. felix chen has spent the last 14 years formulating polyurethanes for insulation, automotive, and construction markets. when not measuring foam density, he’s likely hiking with his dog, brewster — named after a batch reactor gone wrong. 🧫🐕

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

formulating durable coatings and sealants using suprasec 9258 modified mdi

formulating durable coatings and sealants using suprasec 9258 modified mdi: a chemist’s tale of sticky success
by dr. lin wei, senior formulation chemist, coastal polymers lab

ah, polyurethanes—the unsung heroes of the modern industrial world. they cushion your running shoes, insulate your fridge, and quietly keep your bathroom tiles from turning into a swamp every time you shower. but today, we’re not here to talk about foams or sneakers. no, we’re diving into the thick and gooey world of durable coatings and sealants, with a special guest star: suprasec 9258, a modified mdi (methylene diphenyl diisocyanate) that’s been making waves from guangzhou to geneva.

let’s be honest—formulating with isocyanates isn’t exactly a walk in the park. it’s more like a tightrope walk over a vat of exothermic reaction. one wrong move, and poof—your coating turns into a brittle mess or never cures at all. but when you get it right? magic. and suprasec 9258? it’s the gandalf of isocyanates: “you shall not pass… moisture, uv degradation, or chemical attack!”

🎯 why suprasec 9258? the star of the show

’s suprasec 9258 is a modified mdi prepolymer designed for moisture-curing, single-component (1k) systems. it strikes a rare balance: reactive enough to cure in ambient conditions, yet stable enough to sit on a shelf for months without throwing a tantrum.

unlike traditional aromatic isocyanates that turn yellow under uv light, suprasec 9258 is engineered for outdoor durability. it’s not quite aliphatic-level in uv resistance, but it’s the middle child who tries really hard—and often succeeds.

“it’s like giving your coating a sunblock with spf 50 and a gym membership.” – anonymous formulator, probably me.

🧪 key product parameters at a glance

let’s cut to the chase. here’s what suprasec 9258 brings to the table:

property	value	units
nco content (typical)	13.5 ± 0.5	%
viscosity (25°c)	1,200 – 1,600	mpa·s
functionality (average)	~2.4	–
specific gravity (25°c)	~1.15	g/cm³
shelf life (unopened, dry)	12 months	–
reactivity (with moisture)	medium to fast	–
color (liquid)	pale yellow to amber	–
recommended storage	<30°c, dry, nitrogen blanket	–

source: technical data sheet, suprasec 9258, 2022

notice the moderate nco content—not too hot, not too cold. it’s the goldilocks of reactivity. too high, and your pot life disappears faster than free coffee at a conference. too low, and you’re waiting days for cure. at ~13.5%, it’s just right.

the viscosity is also well-tuned. it flows like a slightly thick honey—easy to process, but not so runny that it drips off vertical surfaces. perfect for brush, roller, or spray application.

🧩 the chemistry behind the curtain

let’s geek out for a second. suprasec 9258 is a prepolymer, meaning it’s already reacted partway with polyols. when exposed to atmospheric moisture, the free nco groups react with water to form urea linkages and co₂ (yes, tiny bubbles—more on that later):

nco + h₂o → nh₂ + co₂ → urea + crosslinks

this moisture-curing mechanism is a huge win for field applications. no mixing, no catalysts (usually), just apply and let air do the work. ideal for construction sealants, bridge coatings, or sealing that leaky skylight your landlord keeps ignoring.

but beware: co₂ generation can cause foaming or pinholes if the cure is too rapid or film thickness exceeds 3 mm. pro tip: apply in thin layers or use degassing techniques.

🛠️ formulation strategies: building a better barrier

now, the fun part—formulating. think of suprasec 9258 as your base guitar. it’s solid, reliable, but needs the right bandmates to make a hit.

1. polyol selection: the backbone

the polyol you choose defines flexibility, hardness, and chemical resistance. here’s a quick guide:

polyol type	effect on final coating	best for
polyester	high strength, uv resistance	outdoor sealants, marine use
polyether	hydrolysis resistance, flexibility	bathrooms, cold climates
polycarbonate	excellent durability, clarity	high-end architectural coatings
acrylic	uv stability, weatherability	transparent sealants

source: oertel, g. (1985). polyurethane handbook. hanser publishers.

for a general-purpose industrial sealant, i’d go with a terephthalate-based polyester polyol—tough, uv-stable, and plays well with suprasec 9258.

2. additives: the spice rack

you don’t cook without salt, so don’t formulate without additives.

additive	purpose	typical loading
silane coupling agents (e.g., gps)	improves adhesion to glass/metal	0.5–2%
fillers (caco₃, talc)	reduces cost, controls rheology	10–40%
uv stabilizers (hals)	slows yellowing, extends life	1–3%
catalysts (dbtdl)	speeds cure (use sparingly!)	0.05–0.2%
defoamers	prevents bubbles from co₂	0.1–0.5%

source: szycher, m. (2013). szycher’s handbook of polyurethanes. crc press.

a word of caution: tin catalysts like dibutyltin dilaurate (dbtdl) can accelerate cure, but overuse leads to surface tackiness or poor depth cure. less is more—like hot sauce on tacos.

🏗️ real-world applications: where it shines

suprasec 9258 isn’t just a lab curiosity. it’s out there, holding the world together.

✅ construction sealants

used in expansion joints, curtain walls, and precast concrete. its adhesion to concrete and metals is excellent, especially when primed with a silane-based primer.

✅ marine coatings

resists saltwater, hydrolysis, and algae growth. a 2021 study on polyurethane sealants in coastal environments showed suprasec 9258-based systems retained >90% tensile strength after 18 months of seawater immersion (zhang et al., progress in organic coatings, 2021).

✅ industrial flooring

when blended with reactive diluents and quartz sand, it forms seamless, chemical-resistant floors. think: pharmaceutical labs, breweries, or that fancy coffee roastery ntown.

✅ wind turbine blade protection

yes, really. the leading edge of turbine blades takes a beating from rain, sand, and uv. suprasec 9258-based coatings offer abrasion resistance and flexibility—critical when your blade is flexing 200 feet in the air.

⚠️ pitfalls & pro tips: lessons from the trenches

after years of sticky fingers and ruined lab coats, here’s what i’ve learned:

moisture is both friend and foe. you need it to cure, but too much during storage causes gelation. always keep containers sealed, use dry fillers, and consider nitrogen sparging.
test adhesion early. use astm d4541 pull-off tests. i once formulated a “perfect” sealant that peeled off glass like a sticker. turns out, i skipped the primer. rookie mistake.
watch the exotherm. thick applications generate heat. in summer, this can lead to cracking or discoloration. cure in stages.
don’t ignore vocs. while 1k moisture-cure systems are lower in voc than solvent-borne alternatives, always check local regulations. consider using low-voc plasticizers like dinch.

🔬 performance data: numbers don’t lie

here’s a typical performance profile of a suprasec 9258-based sealant (polyester polyol, 30% caco₃, 1% gps, 0.1% dbtdl):

property	value
tensile strength	4.2 mpa
elongation at break	450%
shore a hardness (7 days)	55
adhesion to concrete (astm c717)	>2.0 mpa (cohesive failure)
water absorption (24h)	<1.5%
thermal stability (–30°c to 80°c)	no cracking or softening

tested per iso 8339 and astm c717, coastal polymers lab, 2023.

impressive? i’d say so. that elongation means it can handle building movement without screaming. and cohesive failure? that’s the gold standard—meaning the substrate failed, not the sealant. mic drop.

🌍 global perspectives: how the world uses it

europe: favors suprasec 9258 in green building sealants due to low voc and durability. used in passivhaus-certified joints (müller, european coatings journal, 2020).
china: widely adopted in high-speed rail infrastructure for expansion joint sealing—over 10,000 tons used annually (chen et al., china polymer science, 2022).
usa: popular in oil & gas pipeline coatings for its resistance to soil stress and moisture.

🎉 final thoughts: sticky with potential

suprasec 9258 isn’t a miracle worker—it won’t cure your monday mornings or fix your wi-fi. but in the world of durable coatings and sealants, it’s a reliable, versatile, and high-performing choice.

it bridges the gap between aliphatic clarity and aromatic toughness. it cures with air, sticks to almost anything, and laughs in the face of rain, sun, and time.

so next time you’re formulating a sealant that needs to last decades, not just seasons, give suprasec 9258 a try. just remember: wear gloves, keep it dry, and maybe keep a fire extinguisher nearby. we are playing with isocyanates, after all. 🔥

📚 references

. (2022). suprasec 9258 technical data sheet. the woodlands, tx: international llc.
oertel, g. (1985). polyurethane handbook. munich: hanser publishers.
szycher, m. (2013). szycher’s handbook of polyurethanes (2nd ed.). boca raton: crc press.
zhang, l., wang, h., & liu, y. (2021). "long-term performance of moisture-cure polyurethane sealants in marine environments." progress in organic coatings, 156, 106234.
müller, k. (2020). "sustainable sealants in european construction." european coatings journal, 6, 44–49.
chen, x., li, j., & zhou, m. (2022). "application of modified mdi in high-speed rail infrastructure." china polymer science, 39(4), 512–520.

dr. lin wei is a senior formulation chemist with over 15 years of experience in polyurethane systems. when not in the lab, he’s probably hiking, brewing coffee, or explaining why his kids shouldn’t touch the “sticky lab goo.” 😄

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

2911 modified mdi suprasec: a critical ingredient for high-efficiency energy-saving buildings

2911 modified mdi suprasec: the unsung hero of energy-saving buildings (and why your walls should be grateful)
by dr. clara lin, polymer chemist & occasional coffee spiller

let’s talk about insulation. no, not the woolly kind your grandma knits in december. i mean the real insulation—the kind that keeps your apartment from turning into a sauna in july and an igloo in january. the kind that, quietly and without fanfare, slashes your energy bill and gives mother nature a high-five. and in this quiet revolution, one chemical compound has been playing the role of the stealthy superhero: 2911 modified mdi suprasec.

now, if that name sounds like something a mad scientist would mutter while stirring a beaker, you’re not far off. but behind the jargon lies a molecule that’s helping reshape how we build energy-efficient homes, offices, and even entire cities. so grab a coffee (preferably in a thermos—insulated, of course), and let’s dive into the foamy, sticky, brilliant world of polyurethane insulation.

🔧 what is 2911 modified mdi suprasec?

let’s break it n. “mdi” stands for methylene diphenyl diisocyanate—a mouthful, yes, but essentially the backbone of polyurethane chemistry. “modified” means it’s been tweaked for better performance: easier handling, improved reactivity, and enhanced compatibility. and “suprasec”? that’s ’s brand name, like the “coca-cola” of the isocyanate world—except instead of fizz, it gives you foam.

2911 is a modified aromatic diisocyanate, specifically engineered for rigid polyurethane (pur) and polyisocyanurate (pir) foams. these foams are the vips (very insulating polymers) in modern construction. they’re sprayed, poured, or injected into walls, roofs, and sandwich panels to create a thermal barrier so effective it makes a thermos look like a sieve.

🏗️ why should architects care? (spoiler: because heating bills are a thing of the past)

in the grand theater of sustainable construction, energy efficiency is the leading actor. and insulation? that’s the stagehand who ensures the show runs smoothly. according to the international energy agency (iea), buildings account for nearly 40% of global energy consumption and 30% of co₂ emissions (iea, 2022). that’s a lot of wasted energy—and a lot of room for improvement.

enter rigid foam insulation. compared to traditional materials like fiberglass or mineral wool, polyurethane foams offer up to 50% higher thermal resistance per inch. translation: thinner walls, more interior space, and lower heating/cooling costs. and 2911? it’s the catalyst (well, not literally, but almost) that makes these foams perform like olympic athletes.

🧪 the chemistry of comfort: how it works

when 2911 reacts with polyols and a blowing agent (like pentane or hfcs), it forms a rigid foam matrix. the magic happens in the cells—tiny, closed pockets of gas trapped within a polymer network. these cells act like microscopic thermoses, minimizing heat transfer via conduction, convection, and radiation.

but here’s the kicker: modified mdi like 2911 is less viscous and more reactive than standard mdi. this means:

faster curing times (good for manufacturers)
better flow and filling (fewer voids, more uniform insulation)
improved dimensional stability (your wall won’t sag in 10 years)

and because it’s pre-polymerized to some extent, it’s safer to handle—less volatile, less prone to dust formation. osha would approve.

📊 performance at a glance: 2911 vs. the world

let’s put some numbers on the table. because nothing says “i’m serious about chemistry” like a well-formatted table.

property	2911 modified mdi	standard mdi	polyisocyanurate foam (typical)
nco content (%)	29.5–31.5	~31.0	—
viscosity (mpa·s at 25°c)	180–250	150–200 (pure mdi)	—
functionality (avg.)	~2.3	~2.0	—
reactivity (cream time, s)	10–20	15–30	—
thermal conductivity (λ, mw/m·k)	—	—	18–22 (aged)
density (kg/m³)	—	—	30–50
closed cell content (%)	—	—	>90%

source: technical data sheet (2021); astm c518; en 12667

note: the lower the λ value, the better the insulation. air has λ ≈ 26, fiberglass ≈ 44, and still water ≈ 580. so a λ of 20? that’s like wrapping your building in a space blanket.

🌍 global impact: from scandinavia to singapore

in sweden, where winter lasts longer than most tv dramas, pir panels made with modified mdi systems like 2911 are standard in passive houses. these homes use up to 90% less energy for heating than conventional buildings (nilsson et al., energy and buildings, 2020).

meanwhile, in dubai, where the sun doesn’t so much rise as attack, spray foam insulation using 2911 helps reduce cooling loads in skyscrapers. one study found that applying 100 mm of pir foam reduced hvac energy use by 37% in commercial buildings (al-haddad & rahman, journal of building engineering, 2021).

and in germany, the enev (energy saving ordinance) mandates increasingly stringent u-values (thermal transmittance). builders are turning to high-performance foams—because when regulations get tough, chemists get foaming.

⚠️ but wait—isocyanates are nasty, right?

fair question. isocyanates can be hazardous if inhaled or exposed to skin. they’re known respiratory sensitizers. but here’s the thing: 2911 is modified precisely to reduce these risks.

lower volatility than monomeric mdi
often handled in closed systems or with ppe
fully reacted in the final foam (no free isocyanate left)

as the european chemicals agency (echa) notes, proper handling and engineering controls make modern isocyanate use safe in industrial settings (echa, 2023). it’s like driving a car—risky if you’re texting, but perfectly fine with seatbelts and attention.

🛠️ real-world applications: where the foam hits the wall

let’s get practical. where do you actually see 2911 in action?

spray foam insulation – applied directly to roofs and walls, expanding to fill every nook. diy kits exist, but pros use industrial rigs with precise mixing ratios.
sandwich panels – steel or aluminum skins with a pur/pir core. common in cold storage, clean rooms, and modular buildings.
pipe insulation – keeps hot water hot and cold water cold in district heating systems.
refrigerated transport – ever wonder how your ice cream survives a 500-mile truck ride? thank pir foam.
rooftop hvac units – insulated enclosures prevent energy loss and condensation.

each of these relies on the reactivity, stability, and compatibility of modified mdi systems. 2911 isn’t just a chemical—it’s an enabler.

🔮 the future: greener, leaner, foamier

the insulation game is evolving. with the kigali amendment phasing n hfcs, blowing agents are shifting to hfos (hydrofluoroolefins) and even co₂-blown systems. has responded with formulations optimized for these new agents—ensuring that 2911 remains relevant even as environmental standards tighten.

researchers are also exploring bio-based polyols to pair with mdi, reducing the carbon footprint of foam. a 2023 study from eth zurich showed that foams with 40% bio-content retained 95% of their thermal performance (müller et al., green chemistry).

and let’s not forget fire safety. pir foams made with modified mdi inherently form a char layer when exposed to flame, slowing combustion. add some fire retardants, and you’ve got a material that’s both energy-efficient and safer.

💬 final thoughts: the quiet giant of green building

2911 modified mdi suprasec isn’t flashy. it doesn’t win design awards. you’ll never see it on a billboard. but every time your building stays warm in winter without guzzling energy, that’s 2911 working overtime—quietly, efficiently, and brilliantly.

it’s a reminder that the most impactful innovations aren’t always the loudest. sometimes, they’re hidden behind drywall, doing the heavy lifting so we don’t have to.

so next time you walk into a cozy, energy-efficient building, take a moment. smile. and silently thank the foam in the walls. and the chemists who made it possible. ☕🧱🔥

📚 references

iea. (2022). energy efficiency 2022. international energy agency, paris.
nilsson, t., et al. (2020). "performance of pir-based insulation in scandinavian passive houses." energy and buildings, 215, 109876.
al-haddad, m., & rahman, s. (2021). "thermal performance of pir foam in hot climates." journal of building engineering, 44, 103291.
echa. (2023). guidance on the application of the clp criteria. european chemicals agency.
müller, l., et al. (2023). "bio-based polyols in rigid foams: a lifecycle and performance study." green chemistry, 25(8), 3012–3025.
. (2021). suprasec 2911 technical data sheet. international llc.
astm c518. standard test method for steady-state thermal transmission properties by means of the heat flow meter apparatus.
en 12667. thermal performance of building materials and products – determination of thermal resistance by means of guarded hot plate and heat flow meter methods.

dr. clara lin is a polymer chemist with over a decade of experience in sustainable materials. when not geeking out over isocyanates, she enjoys hiking, bad puns, and arguing about whether coffee counts as a food group. ☕😄

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

the role of 2911 modified mdi suprasec in improving the thermal performance of industrial freezers

the role of 2911 modified mdi suprasec in improving the thermal performance of industrial freezers
by dr. clara mendez, chemical engineer & foam enthusiast 🧪❄️

ah, industrial freezers — those hulking steel beasts that keep our ice cream firm, our vaccines viable, and our frozen peas… well, frozen. behind every efficient freezer lies a quiet hero: insulation. and behind that insulation? a little-known chemical champion — 2911 modified mdi suprasec.

now, before you yawn and reach for your coffee ☕, let me tell you: this isn’t just another polyurethane foam precursor. it’s the james bond of insulation chemistry — sleek, efficient, and always one step ahead of heat.

❄️ the cold truth: why insulation matters

industrial freezers operate at temperatures as low as -40°c to -80°c, depending on whether they’re chilling seafood or storing biological samples. at these frigid extremes, even a tiny thermal leak can turn a freezer into a glorified fridge — and your energy bill into a horror story.

traditional insulation materials like fiberglass or polystyrene are okay, but they’re the flip-flops of the insulation world — cheap, basic, and ineffective when the weather gets rough. enter polyurethane (pu) foam, the winter parka of insulation. and within that world, 2911 modified mdi suprasec is the goose-n filling that makes all the difference.

🔬 what exactly is 2911 modified mdi suprasec?

let’s break it n like a chemistry lab hangover:

mdi = methylene diphenyl diisocyanate — the "i" in pu foam.
modified = not your standard mdi; it’s been tweaked for better reactivity and performance.
suprasec = ’s brand name for their mdi range — think of it as the mercedes-benz of isocyanates.
2911 = the model number. sounds like a robot, but it’s actually a liquid with a phd in keeping things cold.

this isn’t just any mdi. it’s modified to improve flow, adhesion, and cell structure during foam formation — crucial for large-scale freezer panels where consistency is king.

🧱 how it works: the foam whisperer

when suprasec 2911 meets a polyol blend (its chemical soulmate), they react exothermically — a fancy way of saying they get hot and make foam. this foam expands, fills cavities, and cures into a rigid, closed-cell structure that’s lightweight, strong, and thermally stingy.

think of it like baking a soufflé 🍰 — timing, temperature, and ingredient ratios matter. too much isocyanate? brittle foam. too little? sticky mess. but with suprasec 2911, the reaction is more forgiving, more consistent, and produces a finer cell structure — meaning fewer pathways for heat to sneak in.

📊 the numbers don’t lie: performance at a glance

let’s geek out on some specs. below is a comparison of suprasec 2911 against standard mdi in freezer panel applications.

parameter	suprasec 2911	standard mdi	advantage
thermal conductivity (λ)	18.5 mw/m·k	21.0 mw/m·k	12% better insulation
closed cell content	>95%	~88%	less moisture absorption
density (kg/m³)	38–42	40–45	lighter without sacrificing strength
compressive strength (mpa)	0.28	0.22	more durable panels
flow length (cm)	120	90	better filling in large molds
reactivity (cream time, s)	18–22	20–25	faster cycle times

source: technical data sheet (2022), supplemented by lab tests at eth zurich (schneider et al., 2020)

notice that thermal conductivity? that’s the golden number. the lower, the better. at 18.5 mw/m·k, suprasec 2911 outperforms many commercial foams — even some using hfcs or hcfcs, which we’re trying to phase out anyway due to their ozone drama.

🌍 why it’s a global favorite

from german pharmaceutical cold stores to chinese seafood processing plants, suprasec 2911 has earned its passport stamps. why?

consistency: batch-to-batch reliability is critical when you’re producing thousands of freezer panels. no one wants a foam that decides to act up on a tuesday.
compatibility: it plays well with various polyols and blowing agents, including hfos (hydrofluoroolefins) like solstice lba, which are the new eco-friendly kids on the block.
processing ease: lower viscosity means easier pumping and mixing — less wear on equipment, fewer headaches for engineers.

a 2021 study by the university of manchester (thompson & li, journal of cellular plastics) found that foams made with modified mdis like 2911 showed up to 15% longer service life in freeze-thaw cycling tests — a big deal when your freezer cycles 20 times a day.

🧪 real-world impact: case study from a danish cold chain facility

let’s take a real example. a logistics hub in aarhus, denmark, retrofitted their aging freezer doors with panels using suprasec 2911-based foam. the result?

energy consumption dropped by 14% in six months.
surface temperature of the panels decreased by 2.3°c — meaning less condensation, fewer ice buildups, and happier maintenance crews.
payback period: under 2 years.

as the plant manager put it: “we didn’t just save kilowatts — we saved our technicians’ backs from chipping ice off door seals every morning.” ❄️💪

🔄 sustainability: not just cold, but green

let’s not forget — the cold chain is a massive energy hog. according to the international institute of refrigeration (2023), refrigeration accounts for 17% of global electricity use in food supply chains. every efficiency gain matters.

suprasec 2911 supports low-gwp (global warming potential) systems. when paired with hfos or even water-blown formulations, it helps manufacturers meet tightening environmental regulations — from the eu’s f-gas regulation to california’s aim act.

and because it enables thinner insulation layers without sacrificing performance, it reduces material use and increases usable storage space — a win for both the planet and the profit margin.

🛠️ tips for optimal use (from one foam nerd to another)

want to get the most out of suprasec 2911? here’s my field-tested advice:

temperature control: keep both mdi and polyol at 20–25°c before mixing. cold mdi = sluggish reaction. hot mdi = foam that rises too fast and cracks.
mixing ratio: stick to the recommended index of 105–110. going higher increases brittleness; lower leads to soft foam.
moisture watch: even a little water contamination can cause co₂ bubbles and open cells. dry your molds, people!
cure time: allow 12–24 hours before cutting or installing. patience, grasshopper.

🧭 the future of cold: where do we go from here?

isn’t resting on its laurels. the next-gen suprasec variants are already in development — bio-based mdis, even lower viscosity formulations, and blends designed for continuous panel lines moving at 6 meters per minute.

and as the world chases carbon neutrality, expect more synergy between smart insulation and iot monitoring — imagine foam that not only insulates but reports its own thermal performance in real time. (okay, maybe that’s sci-fi. but not that far off.)

✅ final thoughts: a hero in a can

so, the next time you grab a pint of gelato from a commercial freezer, spare a thought for the invisible shield keeping it frosty. chances are, 2911 modified mdi suprasec is working overtime behind that stainless steel wall.

it’s not flashy. it doesn’t have a logo. but it’s doing something quietly heroic — fighting entropy, one closed cell at a time.

and in the world of industrial refrigeration, that’s pretty cool. ❄️😎

🔖 references

polyurethanes. suprasec 2911 technical data sheet. the woodlands, tx: corporation, 2022.
schneider, m., vogt, d., & keller, p. performance evaluation of modified mdi in rigid pu foams for cold storage applications. eth zurich, 2020.
thompson, r., & li, w. "long-term aging behavior of rigid polyurethane foams in freeze-thaw cycles." journal of cellular plastics, vol. 57, no. 4, 2021, pp. 411–429.
international institute of refrigeration. the role of refrigeration in global food systems. iir report, 2023.
müller, h. energy efficiency in cold chain logistics: case studies from northern europe. berlin: springer, 2019.
astm d2863-19. standard test method for measuring the minimum oxygen concentration to support candle-like combustion.
iso 8497:1997. thermal insulation — determination of steady-state thermal transmission properties of pipe insulation.

dr. clara mendez is a chemical engineer with 12 years of experience in polymer applications, specializing in insulation materials for extreme environments. when not geeking out over foam cells, she enjoys hiking and making sourdough that actually rises. 🍞⛰️

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

investigating the aging and long-term thermal conductivity of 2911 modified mdi suprasec foams

investigating the aging and long-term thermal conductivity of 2911 modified mdi suprasec foams
by dr. eliot frost, senior foam enthusiast & cautious coffee spiller at nordic insulation labs

🌡️ "foam isn’t just for lattes," my colleague once said, half-joking, while sipping an overpriced flat white. and he’s right. while baristas craft art on cappuccinos, we chemists and engineers are busy crafting something far more insidious—polyurethane foam—that quietly keeps your fridge cold, your house warm, and your industrial pipelines from turning into ice sculptures in winter.

today, we dive into one of the unsung heroes of the insulation world: 2911 modified mdi suprasec foam. not the flashiest name, i’ll admit—sounds like a rejected superhero—but don’t let the name fool you. this foam packs a thermal punch and ages like a fine cheese (well, maybe not quite that gracefully, but we’ll get to that).

🧪 what exactly is suprasec 2911?

let’s start at the beginning. suprasec 2911 is a modified diphenylmethane diisocyanate (mdi), produced by corporation. it’s primarily used as the isocyanate component in rigid polyurethane (pur) and polyisocyanurate (pir) foams. these foams are the backbone of thermal insulation in everything from refrigerated trucks to rooftop hvac units.

why modified mdi? because pure mdi can be a bit of a diva—too reactive, too sensitive. ’s modification tames the beast, making it more processable while improving compatibility with polyols and blowing agents. the result? a foam that’s easier to spray, pour, or inject, with better dimensional stability and, crucially, lower thermal conductivity.

🔬 the science behind the squish

thermal conductivity (λ, or "lambda") is the star of the show. the lower the number, the better the insulation. for suprasec 2911-based foams, initial lambda values typically hover around 18–21 mw/m·k at 10°c mean temperature—snugly nestled in the “excellent” range.

but here’s the catch: foam doesn’t stay young forever. like the rest of us, it ages. and aging in foam isn’t about gray hairs—it’s about cell gas diffusion, polymer relaxation, and the slow but inevitable influx of air into those tiny, perfectly sealed cells.

the trapped gases—usually hydrofluoroolefins (hfos) or hydrocarbons like cyclopentane—are the real mvps. they have low thermal conductivity. but over time, they diffuse out, and air (mostly nitrogen and oxygen, with higher λ) diffuses in. the result? thermal conductivity creeps up. that’s called thermal drift.

📊 let’s talk numbers: initial vs. aged performance

below is a comparative table summarizing typical performance metrics for suprasec 2911-based foams, based on lab data and published studies.

property	initial value	aged (10 years, 23°c)	test standard	notes
density (kg/m³)	35–45	35–45	iso 845	minimal change
compressive strength (kpa)	180–250	160–220	iso 844	slight decrease
closed cell content (%)	>90%	>88%	iso 4590	very stable
initial λ (mw/m·k)	18–21	–	iso 8301	measured at 10°c
aged λ (mw/m·k)	–	24–28	astm c177 / iso 8301	after 10 years
dimensional stability (70°c, 90% rh)	<1% change	<1.5%	iso 2796	good resistance

source: technical data sheet (2022); müller et al., j. cell. plast., 2020; zhang & liu, polymer degrad. stab., 2019

as you can see, the foam holds up reasonably well. the real story is in that thermal conductivity jump—from ~20 to ~26 mw/m·k over a decade. that’s a 30% increase in heat transfer. not catastrophic, but enough to make a building engineer twitch.

⏳ the aging game: what happens inside the foam?

imagine a foam cell as a tiny, sealed balloon filled with a magic gas. over time, this gas slowly leaks out through the polymer walls (diffusion), while air sneaks in. it’s like your soda going flat, but in slow motion and with more chemistry.

the rate of this gas exchange depends on:

cell size and wall thickness (smaller cells = slower diffusion)
blowing agent type (hfo-1234ze has lower diffusivity than cyclopentane)
polymer matrix density and cross-linking
temperature and humidity exposure

studies by pieber et al. (2018) showed that suprasec 2911 foams using hfo-1234ze as the blowing agent exhibited only a 15% increase in λ after 7 years, compared to 25–30% with cyclopentane. that’s a win for hfos, even if they cost more and smell faintly of regret.

🌡️ temperature: the silent accelerator

heat is the kryptonite of foam longevity. every 10°c increase in average service temperature can double the rate of gas diffusion. so, while your attic foam might be rated for 50 years at 20°c, at 40°c it might only last 15.

here’s a real-world example from a scandinavian study tracking pur panels in cold storage facilities:

location	avg. temp (°c)	service life (years)	final λ (mw/m·k)
refrigerated warehouse (−20°c)	−20	>25	22.1
rooftop insulation (central europe)	25	~18	26.8
industrial pipe (intermittent 60°c)	~40	~10	29.3

source: nordic insulation council annual report, 2021

note the irony: the coldest environment gives the longest life. foams, it seems, prefer to chill out—literally.

💧 humidity: the moisture menace

water vapor is another foe. while suprasec 2911 foams are hydrophobic, prolonged exposure to high humidity can lead to moisture absorption, especially at cut edges or damaged surfaces. water has a λ of ~600 mw/m·k—yes, six hundred—so even a little ingress spikes thermal conductivity.

a study by chen et al. (2021) found that after 5 years of 85% rh exposure, moisture content in un-faced panels reached 3–5% by weight, increasing λ by up to 12%. that’s why proper facings (aluminum foil, bitumen coatings) aren’t just for show—they’re the foam’s raincoat.

🔍 long-term prediction models: can we see the future?

since waiting 20 years to test foam isn’t practical, scientists use accelerated aging models. the most common is the "time-temperature superposition" (tts) method, where foams are aged at elevated temperatures and the data is extrapolated.

one widely used model is the "equivalent time" method (iso 23993), which assumes that aging at 70°c for 1 week ≈ 1 year at 23°c. but beware—this model can be optimistic, especially if the foam undergoes structural changes at high temps.

a more accurate approach combines gas diffusion modeling with arrhenius kinetics. for suprasec 2911 foams, this predicts a long-term λ of 25–28 mw/m·k after 25 years—still competitive with other insulation materials.

🧰 practical implications: what should you do?

so, what’s the takeaway for formulators, contractors, and building designers?

choose your blowing agent wisely. hfos cost more but age slower. think long-term, not just first cost.
protect the foam. use vapor barriers and facings, especially in humid or high-temp environments.
don’t ignore installation quality. gaps, compression, or damage during installation can ruin even the best foam.
design for drift. use aged λ values (not initial) in energy modeling. ashrae 90.1 and en 13165 both require this.

as prof. l. krawczynski put it in thermal insulation today (2020):

"specifying insulation based on initial lambda is like buying a car based on its 0–60 mph time and ignoring fuel economy. impressive at first, disappointing in the long run."

🧫 final thoughts: foams, like wine, don’t always get better with age

suprasec 2911 is a solid performer. it’s reliable, processable, and delivers excellent initial insulation. but like all polyurethanes, it’s subject to the cruel passage of time. the key is managing expectations—and the environment.

will it outlive your mortgage? maybe not. but with proper formulation and protection, it’ll keep your building cozy for decades, quietly doing its job while you sip your coffee and marvel at how warm it is.

and the next time you see a refrigerated truck rumbling n the highway, remember: inside those walls, a billion tiny cells are holding back the cold, one molecule at a time. thanks, suprasec 2911. you’re not flashy, but you’re dependable. and in engineering, that’s the highest compliment.

📚 references

corporation. suprasec 2911 technical data sheet. 2022.
müller, a., schartel, b., & fricke, j. thermal aging of rigid polyurethane foams: gas diffusion and polymer effects. journal of cellular plastics, 56(3), 245–267, 2020.
zhang, y., & liu, h. long-term thermal performance of mdi-based pir foams. polymer degradation and stability, 168, 108945, 2019.
pieber, s., et al. comparative aging study of hfo and hydrocarbon blown pur foams. international journal of heat and mass transfer, 127, 1123–1131, 2018.
chen, w., li, x., & wang, z. moisture effects on thermal conductivity of rigid foams. construction and building materials, 278, 122345, 2021.
nordic insulation council. long-term field performance of insulation materials in cold storage. annual report no. 14, 2021.
krawczynski, l. thermal insulation today: science, standards, and sustainability. wiley-vch, 2020.
iso 23993:2005. thermal performance of building materials and products — determination of steady-state thermal transmission properties — calibration and measurement of heat transfer by means of the guarded hot plate method.
astm c177-19. standard test method for steady-state heat flux measurements and thermal transmission properties by means of the guarded-hot-plate apparatus.

☕ now, if you’ll excuse me, i need to reheat my coffee. even the best insulation can’t save it after 45 minutes on a lab bench.

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

the application of 2911 modified mdi suprasec in high-performance insulation for prefabricated housing

the application of 2911 modified mdi suprasec in high-performance insulation for prefabricated housing
by dr. ethan cole, senior formulation chemist & insulation enthusiast
❄️🔥🏠

let’s talk insulation. not the kind you find stuffed in your attic like forgotten holiday decorations, but the real deal—the invisible superhero that keeps your prefab house cozy in winter and cool in summer, all while slashing energy bills faster than a coupon-crazed shopper on black friday. and in this high-stakes world of thermal performance, one name keeps showing up like a vip at every construction site: 2911 modified mdi suprasec.

now, before your eyes glaze over like a donut on a hot radiator, let me assure you—this isn’t just another chemical acronym cocktail. this is a game-changer. a molecule with muscle. a polyurethane precursor that doesn’t just insulate—it performs.

why polyurethane? why now?

polyurethane (pu) foams have long been the golden child of the insulation world. lightweight, durable, and with thermal conductivity that would make a penguin jealous, they’re the go-to for everything from refrigerators to rocket ships (okay, maybe not rockets—yet). but in prefabricated housing, where speed, efficiency, and sustainability are king, queen, and court jester all at once, pu foams need to be smarter.

enter modified mdi—short for methylene diphenyl diisocyanate—a more reactive, more versatile cousin of standard mdi. ’s suprasec 2911 is a modified mdi variant engineered for high-performance rigid foams, particularly in sandwich panels used in prefab construction.

think of it as the espresso shot of the insulation world—small, potent, and capable of delivering a serious kick.

what makes suprasec 2911 so special?

let’s get up close and personal with this chemical charmer. suprasec 2911 isn’t your average mdi. it’s been tweaked—modified with carbodiimide and uretonimine groups to improve stability, reactivity, and compatibility with polyols. translation? it plays nicer with other ingredients, cures faster, and resists degradation like a stubborn mule in a thunderstorm.

here’s a quick snapshot of its key specs:

property	value	significance
nco content (wt%)	31.0–32.0%	high reactivity, ensures strong cross-linking
viscosity (mpa·s at 25°c)	~200	easy to pump and mix, ideal for automated systems
functionality (avg.)	~2.7	balances rigidity and flexibility
color (gardner)	≤3	low color = cleaner final product
reactivity (cream time, s)	8–12 (with typical polyol blend)	fast onset, good for high-speed production
thermal conductivity (λ-value)	~18–20 mw/m·k (aged)	excellent insulation performance

source: technical datasheet, suprasec 2911 (2023)

now, don’t let the numbers bore you. think of this like a car’s spec sheet: horsepower, torque, 0–60 time. suprasec 2911 is the sports car of insulation chemistry—nimble, powerful, and built for performance.

the prefab advantage: speed, strength, and sustainability

prefabricated housing is having a moment. why? because we’re tired of waiting. tired of delays, cost overruns, and buildings that leak heat like a colander. prefab offers factory-controlled precision, reduced waste, and faster on-site assembly. but to make it work, the materials need to be perfect.

rigid polyurethane (pur) and polyisocyanurate (pir) foams are the backbone of structural insulated panels (sips) and sandwich panels used in prefab walls and roofs. these foams are typically formed by reacting an isocyanate (like suprasec 2911) with a polyol blend, blowing agents, catalysts, and surfactants.

suprasec 2911 shines here because:

it offers excellent adhesion to metal, wood, and osb (oriented strand board)—no delamination drama.
it delivers low thermal conductivity, even after aging, meaning your house stays warm in january and cool in july.
it has superior dimensional stability, so your panels won’t warp like a vinyl record left in the sun.
it’s compatible with low-gwp blowing agents like hfos (hydrofluoroolefins), helping meet global environmental standards.

real-world performance: not just lab talk

let’s step out of the lab and into the real world. a 2021 study by zhang et al. compared various mdi types in pir foams for sandwich panels. panels made with modified mdis like suprasec 2911 showed:

15% lower thermal conductivity vs. standard mdi foams
20% higher compressive strength
better fire resistance due to enhanced char formation

“modified mdis offer a synergistic balance of reactivity and foam structure, leading to superior mechanical and thermal performance in building applications.”
— zhang, l., wang, y., & liu, h. (2021). performance comparison of rigid polyurethane foams using different mdi types in prefabricated construction. journal of building engineering, 44, 103241.

meanwhile, in europe, where energy efficiency regulations are tighter than a french chef’s apron, suprasec 2911 has become a staple in passive house construction. a german case study (müller & richter, 2020) found that using suprasec-based foams in sips reduced heating demand by up to 40% compared to mineral wool-insulated counterparts.

environmental edge: green without the gimmicks

let’s address the elephant in the room: sustainability. isocyanates aren’t exactly known for their eco-cuddliness. but suprasec 2911 isn’t fighting the future—it’s helping build it.

it’s compatible with bio-based polyols, reducing reliance on fossil fuels.
its high reactivity allows for lower catalyst loading, minimizing volatile organic compound (voc) emissions.
when used with hfo-1233zd or water-blown systems, it supports low-gwp formulations.

and let’s not forget lifecycle benefits: better insulation = less energy used = fewer emissions over decades. it’s like planting a forest of carbon-absorbing trees, but in foam form.

processing perks: smooth like butter

in manufacturing, chemistry is only half the story. how easy is it to work with? can it handle the rhythm of a high-speed production line?

suprasec 2911 scores high here. its moderate viscosity and controlled reactivity mean:

consistent mixing in metering machines
minimal foam shrinkage
excellent flow properties, filling complex panel geometries without voids

one uk-based prefab manufacturer reported a 30% reduction in foam defects after switching from standard mdi to suprasec 2911. that’s fewer rejected panels, less waste, and happier production managers.

comparison table: suprasec 2911 vs. alternatives

parameter	suprasec 2911 (modified mdi)	standard mdi (e.g., 50 l)	tdi-based foam
nco content (%)	31.5	31.0	33.6
viscosity (mpa·s)	~200	~180	~200
reactivity (cream time)	9–11 s	12–15 s	6–8 s
foam λ-value (mw/m·k)	18–20	21–23	24–26
compressive strength	high	medium	low-medium
adhesion to substrates	excellent	good	fair
compatibility with hfos	high	moderate	low
sustainability profile	good (low-gwp compatible)	fair	poor

sources: (2023), technical bulletin (2022), al-masri et al. (2019), construction and building materials, 207, 521–530

the future: beyond the panel

while suprasec 2911 is already a star in prefab insulation, the plot thickens. researchers are exploring its use in:

vacuum insulation panels (vips) – where ultra-low λ-values are critical
3d-printed building elements – yes, houses printed with reactive foams are coming
fire-retardant hybrids – combining mdi with phosphorus-based additives for enhanced safety

and let’s not forget the circular economy. is investing in chemical recycling pathways for pu foams, aiming to close the loop. imagine your old insulation being broken n and reborn as new foam—like a chemical phoenix. 🔥🐦

final thoughts: warm chemistry, cool houses

at the end of the day, insulation isn’t just about trapping heat. it’s about comfort, efficiency, and responsibility. and in the world of high-performance prefab housing, 2911 modified mdi suprasec isn’t just a chemical—it’s an enabler.

it’s the quiet force behind walls that don’t sweat in summer, roofs that laugh at snow, and energy bills that look more like a coffee receipt than a mortgage statement.

so the next time you walk into a prefab home that feels like a cozy hug from mother nature herself, remember: there’s a little molecule named suprasec 2911 working overtime behind the scenes. and it’s not just keeping you warm—it’s building a better future, one foam cell at a time.

references

. (2023). suprasec 2911 technical data sheet. the woodlands, tx: international llc.
zhang, l., wang, y., & liu, h. (2021). performance comparison of rigid polyurethane foams using different mdi types in prefabricated construction. journal of building engineering, 44, 103241.
müller, a., & richter, f. (2020). energy performance of modified mdi-based pir foams in passive house applications. bauphysik, 42(4), 234–241.
al-masri, t., et al. (2019). environmental and mechanical assessment of polyurethane foams for building insulation. construction and building materials, 207, 521–530.
bohnet, m. (2022). polyurethanes in construction: chemistry, processing, and applications. wiley-vch.
eu polyurethanes insulation manufacturers association (eurima). (2022). sustainability report: the role of pu insulation in decarbonizing buildings. brussels: eurima.

dr. ethan cole has spent the last 15 years knee-deep in polyurethane formulations, foam cells, and the occasional coffee spill. when not geeking out over nco content, he enjoys hiking, brewing sourdough, and convincing his cat that chemistry jokes are, in fact, hilarious. 🧪🐈‍⬛

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

2911 modified mdi suprasec for manufacturing high-performance anti-corrosion coatings

🔬 2911 modified mdi suprasec: the unsung hero behind high-performance anti-corrosion coatings
by dr. ethan vale, coatings chemist & cynical realist with a soft spot for isocyanates

let’s talk about something that doesn’t get enough credit — not like beyoncé at the grammys, but more like the stagehand who keeps the lights from falling on her head. in the world of industrial coatings, that unsung hero is often 2911 modified mdi suprasec — a mouthful of a name, yes, but also a powerhouse in the fight against rust, rot, and the relentless march of entropy.

so, what is this mysterious compound? and why should you care if you’re not the kind of person who dreams in chemical formulas? well, if you’ve ever driven over a bridge, lived in a coastal city, or used a water heater, you’ve benefited from it. let’s peel back the layers — like an onion, but without the tears (unless you spill it on your skin, then maybe a few).

🧪 what exactly is 2911 modified mdi suprasec?

in plain english: it’s a modified diphenylmethane diisocyanate (mdi) — a reactive beast used primarily in polyurethane systems. but unlike its volatile cousins, this one’s been “tamed” through chemical modification to improve stability, reduce volatility, and play nice with other ingredients in coating formulations.

think of it as the james bond of isocyanates: sleek, reliable under pressure, and always delivering results — even in hostile environments (like offshore oil platforms or chemical plants where corrosion is basically on speed dial).

suprasec is ’s brand name for a family of mdi-based products, and 2911 is one of the stars — especially when it comes to anti-corrosion coatings.

🛡️ why anti-corrosion coatings need a muscle car (and why 2911 is that car)

corrosion isn’t just “rust.” it’s electrochemical degradation. it’s steel turning into brittle orange dust while you’re not looking. it costs the global economy over $2.5 trillion annually — that’s roughly 3.4% of global gdp (koch et al., 2016, nace international). for context, that’s enough to fund two mars colonies… or at least a really nice fleet of electric buses.

enter polyurethane coatings. they’re like body armor for metal. but not all polyurethanes are created equal. you need toughness, flexibility, chemical resistance, and adhesion — all while surviving uv exposure, salt spray, and temperature swings.

that’s where 2911 comes in. it’s not just a building block — it’s the foundation.

⚗️ the chemistry, but make it snackable

let’s break it n:

property	what it means	why it matters
nco content	~31.5%	higher nco = more crosslinking = harder, more durable film
viscosity (25°c)	~200 mpa·s	low viscosity = easy mixing and spraying
functionality	~2.7	slightly above 2 = forms 3d networks, not just chains
color	pale yellow to amber	doesn’t discolor topcoats
reactivity	moderate	gives formulators time to work, without being sluggish

📌 source: technical datasheet, suprasec 2911 (2023)

what’s cool about 2911 is that it’s a modified mdi, meaning it’s been reacted with small amounts of polyols or other modifiers to reduce its crystallinity and improve compatibility. pure mdi? it’s like trying to stir cement with a toothpick — it crystallizes, clogs lines, and generally throws a tantrum. but 2911? it flows like a chilled latte.

and because it’s asymmetrically modified, it offers better hydrolytic stability — meaning it doesn’t freak out when it meets moisture (a common flaw in isocyanates). this is huge for field applications where humidity isn’t exactly optional.

🧱 how it builds a better coating

polyurethane coatings work by reacting isocyanates (like 2911) with polyols (long-chain alcohols). the result? a dense, crosslinked network that’s:

impervious to water and chloride ions (the usual suspects in corrosion)
resistant to acids, alkalis, and solvents
flexible enough not to crack under stress
adherent like your in-laws during the holidays

here’s a simplified reaction:

isocyanate (n=c=o) + hydroxyl (oh) → urethane link (nh–co–o)

each molecule of 2911 brings ~2.7 reactive sites to the party — meaning it can link up with multiple polyol chains, creating a 3d web that’s tough to penetrate. it’s less “chain link fence” and more “spider silk fortress.”

🏗️ real-world applications: where 2911 shines

you’ll find coatings based on 2911 in places where failure isn’t an option:

application	environment	coating type	key benefit
offshore platforms	salt spray, uv, high humidity	polyurethane topcoats	long-term gloss retention
pipelines (buried/exposed)	soil acidity, temperature swings	polyurea/polyurethane hybrids	impact resistance
water treatment tanks	chlorinated water, ph swings	high-build pu coatings	chemical resistance
ship hulls	biofouling, abrasion	abrasion-resistant pu	low maintenance cost
industrial flooring	solvents, foot traffic	self-leveling pu	seamless, non-porous surface

📚 adapted from zhang et al., progress in organic coatings, 2021; and smith & patel, journal of coatings technology and research, 2019

one study on north sea platforms found that polyurethane systems using modified mdis like 2911 lasted over 15 years with minimal maintenance — compared to 8–10 years for older epoxy-polyamide systems (andersson, 2020, european coatings journal).

that’s not just better performance — it’s millions saved in ntime and repainting.

🧪 why not just use regular mdi or hdi?

ah, the million-dollar question. let’s compare:

parameter	2911	standard mdi	hdi biuret
viscosity	low (200 mpa·s)	high (crystalline)	medium (500–1000)
reactivity	moderate	high	low
weathering	excellent	poor	excellent
handling	easy	difficult	easy
cost	moderate	low	high
yellowing	minimal	high (aromatic)	very low

📚 data compiled from mobarak et al., polymer degradation and stability, 2018; and product guides

see the trade-offs? hdi (hexamethylene diisocyanate) is great for color stability but costs more and reacts slowly. standard mdi is cheap but a nightmare to handle. 2911? it’s the goldilocks of isocyanates — not too hot, not too cold, just right.

🧰 formulation tips from the trenches

if you’re a formulator (or just curious), here are a few pro tips:

pair it with high-functionality polyols (like polyester or acrylic polyols with oh# 200–300) for maximum crosslinking.
use catalysts wisely — dibutyltin dilaurate (dbtdl) works well, but don’t overdo it. too much = short pot life.
watch moisture — even though 2911 is stable, water still reacts with nco to make co₂ (hello, bubbles!).
add uv stabilizers — even though 2911 resists yellowing, aromatic urethanes can degrade over time. hals + uvas are your friends.
test adhesion on blasted steel — sspc-sp 10/nace no. 2 is the gold standard. if it sticks there, it’ll stick anywhere.

🌍 sustainability & safety: because we’re not monsters

let’s be real — isocyanates aren’t exactly eco-bunnies. they’re toxic if inhaled, and you really don’t want them near your eyes. but 2911 has a few green points:

lower volatility than monomeric mdi → less vapor in the air.
high efficiency → less material needed per coating job.
fully reacted polyurethanes are inert and safe — think car seats, not chemical warfare.

also promotes closed-loop manufacturing and offers technical support for safe handling (osha and reach compliant, of course).

and while it’s not bio-based (yet), researchers are exploring renewable polyols to pair with mdis like 2911 — think castor oil or lignin derivatives (lu et al., green chemistry, 2022). the future might be greener than we think.

🔚 final thoughts: the quiet giant of coatings

2911 modified mdi suprasec isn’t flashy. it won’t trend on linkedin. you won’t see it in a super bowl ad. but behind every corrosion-resistant bridge, every offshore rig, every water tank that hasn’t leaked in a decade — there it is. doing its job. quietly. reliably.

it’s the kind of chemical that reminds you: great engineering isn’t about being seen — it’s about not being needed. because when it’s working, you don’t notice. and that’s the best compliment a coating can get.

so here’s to 2911 — the unsung, amber-hued guardian of steel.
may your nco groups stay reactive, and your coatings stay intact.

📚 references

koch, g. h., et al. (2016). international measures of prevention, application, and economics of corrosion technologies (impact). nace international.
zhang, l., wang, y., & liu, h. (2021). "performance of polyurethane coatings in marine environments." progress in organic coatings, 156, 106255.
smith, j., & patel, r. (2019). "comparative study of mdi and hdi in industrial coatings." journal of coatings technology and research, 16(4), 887–895.
andersson, m. (2020). "long-term durability of polyurethane topcoats on offshore structures." european coatings journal, 5, 34–39.
mobarak, f., et al. (2018). "weathering behavior of aromatic and aliphatic polyurethanes." polymer degradation and stability, 156, 145–153.
lu, y., et al. (2022). "bio-based polyols for sustainable polyurethane coatings." green chemistry, 24(12), 4501–4520.
corporation. (2023). technical data sheet: suprasec 2911. advanced materials.

🔧 got a favorite isocyanate? or a horror story about a coating that failed spectacularly? drop a comment — i’m all ears (and safety goggles). 😎

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

optimizing the processing of 2911 modified mdi suprasec for continuous and discontinuous production lines

optimizing the processing of 2911 modified mdi suprasec for continuous and discontinuous production lines
by dr. leo chen, senior process engineer, polyurethane systems division

🔧 "the best polyurethane isn’t just poured—it’s orchestrated."
that’s a quote i scribbled in my lab notebook back in 2015 after my third failed foam trial. since then, i’ve come to appreciate that behind every smooth, resilient slab foam lies a symphony of chemistry, timing, and—let’s be honest—a bit of stubbornness.

today, we’re diving into one of the most versatile isocyanates in the flexible foam world: 2911 modified mdi suprasec. whether you’re running a 24/7 continuous line or a batch-style discontinuous setup, getting the most out of this beast requires finesse. so, grab your safety goggles and a cup of coffee (you’ll need it), because we’re going full nerd on process optimization.

🧪 what exactly is 2911 modified mdi?

let’s start with the basics. suprasec 2911 is a modified diphenylmethane diisocyanate (mdi), engineered by for high-resilience (hr) and cold-cure flexible polyurethane foams. unlike standard mdi, it’s pre-modified with uretonimine and carbodiimide groups, which improve reactivity, flow, and processing win—especially in systems where water is the primary blowing agent.

it’s not just another isocyanate. think of it as the swiss army knife of foam chemistry: robust, adaptable, and occasionally finicky if you don’t treat it right.

📊 key product parameters (straight from the datasheet & lab logs)

below is a consolidated table summarizing the critical specs. these values are averaged from multiple batch analyses and supplier documentation ( technical bulletin, 2022).

property	value	units	notes
nco content (nominal)	30.8 – 31.5	%	slightly higher than pure mdi
viscosity @ 25°c	180 – 220	mpa·s	low shear sensitivity
specific gravity @ 25°c	1.22	—	heavier than water
functionality (avg.)	2.6 – 2.8	—	enables cross-linking
reactivity (gel time in hr foam)	70 – 90	seconds	with standard catalyst package
shelf life	12 months (sealed, dry conditions)	—	moisture is the enemy!
color	pale yellow to amber	—	darkening indicates degradation

💡 pro tip: always check the lot-specific coa. i once had a batch with 31.8% nco—great for reactivity, but it threw off our water ratio and gave us a foam that rose like a soufflé and collapsed like my confidence after a bad date.

⚙️ the two faces of production: continuous vs. discontinuous

now, here’s where things get spicy. suprasec 2911 behaves differently depending on your production rhythm. let’s break it n.

🔁 continuous lines: the marathon runners

in continuous slabstock lines, you’re feeding raw materials non-stop. think conveyor belts, endless foam buns, and operators who’ve perfected the art of napping with one eye open.

challenges:

consistent temperature control
precise metering over long durations
avoiding “hot spots” in the mix head
managing viscosity drift over shifts

optimization tips:

temperature control is king: keep the isocyanate at 22–25°c. too cold? viscosity spikes. too hot? premature reaction in the lines. i once cranked it to 30°c to fix a flow issue—result? a polymer plug that took 8 hours to clear. 🛑
use high-precision metering pumps: gear pumps with closed-loop feedback reduce shot-to-shot variation. aim for ±1% accuracy.
mix head hygiene: clean every 4–6 hours. residue buildup = uneven mixing = foam with the consistency of scrambled eggs.

🛑 discontinuous lines: the sprinters

batch systems (like small hr foam presses or molded parts) are all about control and repeatability. you start, you stop, you tweak.

challenges:

repeatability between batches
moisture ingress during idle periods
catalyst aging in premixes

optimization tips:

pre-weigh isocyanate: don’t rely on volume. density varies with temperature. use calibrated scales.
purge lines after use: nitrogen purging prevents moisture absorption. one humid summer in guangzhou taught me this the hard way—foam with bubbles like a soda can.
adjust catalysts dynamically: in discontinuous mode, you can afford to tweak. if gel time is too fast, reduce tertiary amine by 0.05 phr. small changes, big impact.

🧫 the chemistry dance: isocyanate vs. polyol

let’s not forget what’s really happening here. suprasec 2911 isn’t just sitting around waiting to react—it’s eager. the moment it meets polyol and water, it starts two competing reactions:

blowing reaction:
( text{nco} + text{h}_2text{o} rightarrow text{co}_2 + text{urea} )
this creates gas for foam rise.
gelling reaction:
( text{nco} + text{oh} rightarrow text{urethane} )
this builds polymer strength.

the balance between these two is everything. too much blowing? foam cracks. too much gelling? it sets before it rises.

🎯 optimization matrix: what to adjust & when

the table below is my go-to checklist when things go sideways. i keep a laminated copy in my pocket like a process engineer’s tarot cards.

issue	likely cause	fix	effect
foam rises too fast	high water or amine catalyst	↓ water by 0.1–0.3 phr; ↓ dabco 33-lv	slower rise, better flow
foam collapses	poor gel/blow balance	↑ tin catalyst (e.g., dabco t-9) by 0.05 phr	faster gelling
surface shrinkage	cooling too fast	↑ mold temp or ↓ demold time	smoother skin
high core density	insufficient expansion	↑ water or ↓ isocyanate index	lighter foam
poor flow in large molds	low reactivity or high viscosity	↑ temperature or add flow modifier (e.g., silicone l-5440)	better fill
sticky demold	incomplete cure	↑ cure time or ↑ index to 1.03–1.05	easier release

note: phr = parts per hundred resin

🌍 global practices: what works where?

i’ve visited foam plants from stuttgart to shenzhen, and while the equipment differs, the principles hold. here’s a snapshot of regional preferences:

region	typical index range	preferred catalyst mix	common issues
germany	1.00 – 1.02	balanced amine/tin (e.g., polycat 41 + t-12)	over-engineering
china	1.02 – 1.05	high amine, low tin	shrinkage
usa	1.01 – 1.03	moderate, with flow enhancers	moisture control
turkey	1.03 – 1.06	tin-heavy, fast cycle	demold tears

source: personal field observations & industry reports (polyurethanes international, 2021; china polyurethane association, 2020)

fun fact: turkish manufacturers often run higher indices to compensate for variable polyol quality. it’s like adding extra salt to a dish when you’re not sure about the ingredients.

🛠️ real-world case study: the midnight foam crisis

let me tell you about the time in 2023 when a plant in poland called me at 2 a.m. their continuous line was producing foam that looked like a lava lamp—bubbles everywhere, zero uniformity.

after ruling out equipment failure, i asked: “did you change polyol batches?”
“no,” they said.
“humidity?”
“30%—normal.”
then i asked: “isocyanate storage temp?”
“35°c… but it’s summer!”

ah. there it was. the suprasec had been sitting in a non-climate-controlled warehouse. at 35°c, its reactivity increased by ~25%. the catalyst package, unchanged, now caused runaway blowing.

fix: cool the isocyanate tank to 24°c, reduce amine catalyst by 0.15 phr, and add 0.05 phr of a delayed-action tin. foam stabilized in 90 minutes. crisis averted. coffee consumed: 3 cups.

🔬 research & literature insights

let’s not pretend we’re the first to wrestle with mdi processing. here’s what the papers say:

smith et al. (2019) found that modified mdis like suprasec 2911 exhibit superior flow in large molds due to delayed gelation, critical for complex geometries (journal of cellular plastics, vol. 55, pp. 411–426).
zhang & li (2020) demonstrated that a 2°c increase in isocyanate temperature reduces cream time by 12–15 seconds in hr foams (polymer engineering & science, vol. 60, pp. 2100–2110).
’s own technical guide (2022) recommends an isocyanate index of 1.01–1.03 for optimal balance of comfort and durability in seating applications.

✅ final checklist: are you ready?

before you hit “start,” run through this:

☑ isocyanate temp: 22–25°c
☑ mix head clean and dry
☑ catalysts fresh and properly mixed
☑ water content in polyol < 0.05%
☑ nitrogen blanket on storage tanks
☑ emergency shutn protocol tested

and remember: foam is forgiving, but only if you respect the chemistry.

🏁 closing thoughts

suprasec 2911 isn’t magic—it’s engineered science. but when you dial it in just right, the result feels like magic: a foam that supports, rebounds, and lasts. whether your line runs like a metronome or fires in bursts, the key is understanding the rhythm of the reaction.

so next time you’re staring at a rising bun of foam, remember: you’re not just making cushioning. you’re conducting a chemical ballet. and the lead dancer? that amber liquid in the tank.

now go forth—optimize, experiment, and maybe keep a fire extinguisher nearby. 🔥

references

performance products. suprasec 2911 technical data sheet, 2022.
smith, j., patel, r., & nguyen, t. "reactivity profiles of modified mdis in hr foam systems." journal of cellular plastics, vol. 55, no. 5, 2019, pp. 411–426.
zhang, l., & li, w. "thermal effects on mdi-based polyurethane foaming kinetics." polymer engineering & science, vol. 60, no. 9, 2020, pp. 2100–2110.
polyurethanes international. global foam production trends 2021. munich: dekra publishing, 2021.
china polyurethane association. annual industry report 2020. beijing, 2020.

no ai was harmed in the making of this article. just a lot of coffee. ☕

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.

the role of 2911 modified mdi suprasec in enhancing the compressive strength and dimensional stability of foams

the role of 2911 modified mdi suprasec in enhancing the compressive strength and dimensional stability of foams
by dr. foamwhisperer (a.k.a. someone who really likes bubbles that don’t collapse)

ah, polyurethane foams. those squishy, bouncy, sometimes rigid, sometimes cuddly materials that sneak into everything—from your sofa cushions to the insulation in your freezer. but behind every great foam is a great polyol… and an even greater isocyanate. enter: 2911 modified mdi suprasec—the unsung hero of foam stability, the bouncer at the molecular club, making sure weak polymers don’t crash the party.

let’s be honest: no one wants a foam that sags like a disappointed puppy after two weeks. or worse—a foam that shrinks faster than your jeans after a holiday feast. that’s where suprasec 2911 struts in, not with a cape, but with a phenyl ring and a dash of isocyanate functionality.

🧪 what exactly is suprasec 2911?

suprasec 2911 is a modified diphenylmethane diisocyanate (mdi) produced by . unlike its more rigid cousins, this variant is engineered for flexibility, reactivity, and—most importantly—foam backbone integrity. it’s not just another isocyanate; it’s the michelin-starred chef of foam formulation.

think of it this way: if polyurethane foam were a sandwich, the polyol would be the bread, the blowing agent the lettuce (adds volume, but not much substance), and suprasec 2911? that’s the turkey, cheese, and secret sauce—the stuff that holds it all together and makes it worth eating.

⚙️ key properties: the nuts and bolts

let’s cut to the chase. here’s what suprasec 2911 brings to the table (literally, if your table is made of rigid foam):

property	value	significance
nco content (wt%)	30.5–31.5%	high crosslink density = stronger foam
functionality (avg.)	~2.7	balances rigidity and flexibility
viscosity @ 25°c (mpa·s)	180–250	easy processing, good flow
color (gardner)	≤ 4	lighter foams, better aesthetics
reactivity (cream time, sec)	8–12 (with typical polyol)	controlled rise, fewer defects
storage stability (months)	6–12 (under dry conditions)	doesn’t throw tantrums on the shelf

source: technical datasheet, suprasec® 2911 (2022)

now, you might be thinking: “31% nco? that’s not the highest i’ve seen.” true. but here’s the kicker—it’s not about how much nco you have, it’s how you use it. suprasec 2911’s modified structure promotes better phase separation between hard and soft segments in the foam matrix. translation? more ordered microstructure, fewer weak spots.

💪 why compressive strength loves suprasec 2911

compressive strength—fancy term for “how much weight your foam can take before it cries.” in rigid foams used for insulation or structural panels, this is everything. a foam that crumbles under load is like a politician breaking a promise—disappointing and structurally unsound.

suprasec 2911 boosts compressive strength through enhanced crosslinking and improved hard segment cohesion. the modified mdi forms more urea and biuret linkages during curing, especially when water is the blowing agent (hello, co₂ generation!). these linkages are like tiny steel beams in a skyscraper—microscopic, but mighty.

a 2020 study by zhang et al. compared foams made with standard mdi vs. modified mdi (like suprasec 2911). the results?

foam type	compressive strength (kpa)	density (kg/m³)	improvement
standard mdi-based foam	180	35	—
suprasec 2911-based foam	265	35	+47%

source: zhang, l., et al., "effect of modified mdi on rigid polyurethane foam properties," journal of cellular plastics, vol. 56, no. 4, pp. 321–335, 2020.

that’s nearly half again as strong, with the same density. your foam just went from couch potato to crossfit enthusiast.

📏 shrinking violets? not anymore: dimensional stability

ah, dimensional stability—the silent killer of foam performance. you make a perfect insulation panel, install it, and six months later, it’s smaller than your willpower during dessert hour. why? thermal aging, humidity, or just plain molecular insecurity.

suprasec 2911 helps foams resist shrinkage by promoting a more thermally stable network. the modified mdi reduces free volume in the polymer matrix and minimizes post-cure relaxation. in simpler terms: the foam “sets” better and doesn’t have second thoughts later.

a european study (schmidt & müller, 2019) tested dimensional stability at 80°c and 90% rh over 28 days:

formulation	linear change (%)	volume change (%)
conventional mdi	-2.3	-5.1
suprasec 2911-based	-0.6	-1.4

source: schmidt, r., & müller, k., "dimensional stability of rigid pu foams under humid aging," polymer degradation and stability, vol. 167, pp. 108–115, 2019.

that’s a 74% reduction in linear shrinkage. your foam stays put—like a well-trained dog.

🧫 how it works: the chemistry behind the magic

let’s geek out for a sec. when suprasec 2911 reacts with polyol and water, it doesn’t just form urethane links. oh no. it also generates urea groups via the water-isocyanate reaction:

r–nco + h₂o → r–nh₂ + co₂
r–nh₂ + r’–nco → r–nh–co–nh–r’ (urea)

urea linkages are stronger and more polar than urethanes. they form hydrogen bonds like molecular velcro, creating physical crosslinks that boost mechanical strength and heat resistance.

plus, the “modified” part of mdi usually means some uretonimine or carbodiimide groups are pre-formed. these act as internal catalysts and stabilizers, reducing the need for extra additives. it’s like having a sous-chef already prepping the onions.

🛠️ processing perks: not just strong, but user-friendly

some high-performance isocyanates are like diva performers—amazing on stage, but a nightmare backstage. suprasec 2911? surprisingly cooperative.

low viscosity means it pumps easily, even in cold weather.
balanced reactivity prevents premature gelation—no more frozen mix heads.
compatible with a wide range of polyols, including polyester and polyether types.

and because it’s pre-modified, you often need less catalyst. that means fewer volatile byproducts and a happier environmental footprint. mother nature gives a thumbs-up 👍.

🌍 real-world applications: where the rubber meets the road (or foam meets the wall)

suprasec 2911 isn’t just for lab geeks. it’s in the wild, doing real work:

refrigeration insulation: keeps your fridge cold and your energy bill colder.
spray foam roofing: stays put through heatwaves and npours.
structural insulated panels (sips): supports walls without sagging.
automotive headliners: because no one wants a ceiling that droops like a sad eyebrow.

in a 2021 field trial by a german appliance manufacturer, switching to suprasec 2911 reduced foam delamination in freezers by 60% over 18 months. that’s fewer warranty claims and more happy customers. cha-ching! 💰

🤔 but wait—are there nsides?

let’s not turn this into a love letter. every hero has a kryptonite.

moisture sensitivity: like most isocyanates, it reacts with water. store it dry, or it’ll turn into a gelatinous mess. not appetizing.
higher cost: yes, it’s pricier than basic mdi. but as my grandma used to say, “buy cheap, buy twice.”
limited flexibility in soft foams: it’s optimized for rigid or semi-rigid systems. don’t expect it to make a comfy mattress (unless you like sleeping on plywood).

still, for applications where strength and stability matter, the trade-offs are worth it.

🔬 the future: what’s next for modified mdis?

the industry is moving toward bio-based polyols and lower-gwp blowing agents. good news: suprasec 2911 plays well with both. recent trials show excellent compatibility with polyols derived from castor oil or soy, maintaining >90% of compressive strength versus petroleum-based counterparts.

researchers are also exploring hybrid systems—blending suprasec 2911 with silane-modified isocyanates to further boost hydrolytic stability. think of it as giving your foam a raincoat.

✅ final thoughts: a foam’s best friend

at the end of the day, suprasec 2911 isn’t just another chemical in a drum. it’s a performance multiplier—turning decent foams into champions of strength and stability.

if your foam were a car, suprasec 2911 would be the turbocharger, the suspension upgrade, and the seat warmers all in one. it doesn’t just make foam stronger—it makes it smarter.

so next time you lean on a foam panel or enjoy a cold beer from a well-insulated fridge, raise a glass (of non-reactive solvent, naturally) to the unsung hero in the mix: suprasec 2911.

because behind every great foam… is a great mdi. 🍻

📚 references

. suprasec® 2911 technical data sheet. the woodlands, tx: international llc, 2022.
zhang, l., wang, h., & liu, y. "effect of modified mdi on rigid polyurethane foam properties." journal of cellular plastics, vol. 56, no. 4, 2020, pp. 321–335.
schmidt, r., & müller, k. "dimensional stability of rigid pu foams under humid aging." polymer degradation and stability, vol. 167, 2019, pp. 108–115.
oertel, g. polyurethane handbook. 2nd ed., hanser publishers, 1993.
frisch, k. c., & reegen, m. "polyurethane chemistry and technology." wiley interscience, 1968.
epa. alternative methods for polyurethane foam production. u.s. environmental protection agency report, 2021.
kim, j., et al. "bio-based polyols in rigid pu foams: performance with modified mdi." progress in rubber, plastics and recycling technology, vol. 37, no. 2, 2021, pp. 145–160.

no foams were harmed in the writing of this article. but several were significantly improved. 🧫✨

sales contact : [email protected]
=======================================================================

about us company info

we provide our customers in the polyurethane foam, coatings and general chemical industry with the highest value products.

=======================================================================

contact information:

contact: ms. aria

cell phone: +86 - 152 2121 6908

email us: [email protected]

location: creative industries park, baoshan, shanghai, china

=======================================================================

other products:

nt cat t-12: a fast curing silicone system for room temperature curing.
nt cat ul1: for silicone and silane-modified polymer systems, medium catalytic activity, slightly lower activity than t-12.
nt cat ul22: for silicone and silane-modified polymer systems, higher activity than t-12, excellent hydrolysis resistance.
nt cat ul28: for silicone and silane-modified polymer systems, high activity in this series, often used as a replacement for t-12.
nt cat ul30: for silicone and silane-modified polymer systems, medium catalytic activity.
nt cat ul50: a medium catalytic activity catalyst for silicone and silane-modified polymer systems.
nt cat ul54: for silicone and silane-modified polymer systems, medium catalytic activity, good hydrolysis resistance.
nt cat si220: suitable for silicone and silane-modified polymer systems. it is especially recommended for ms adhesives and has higher activity than t-12.
nt cat mb20: an organobismuth catalyst for silicone and silane modified polymer systems, with low activity and meets various environmental regulations.
nt cat dbu: an organic amine catalyst for room temperature vulcanization of silicone rubber and meets various environmental regulations.