Huntsman Suprasec-5005 in Wood Binders and Composites: A Solution for High Strength and Water Resistance.

Date：2025-08-09 Categories：News

Huntsman Suprasec-5005 in Wood Binders and Composites: A Solution for High Strength and Water Resistance
By Dr. Alan Foster – Senior Formulation Chemist, TimberTech Labs

Let’s talk glue. Not the kind you used to stick macaroni onto cardboard in third grade (though I still have that masterpiece framed in my basement), but the kind that holds together engineered wood products that go into your kitchen cabinets, your deck, and even the floors of high-rise buildings. In the world of wood composites, where moisture and mechanical stress are constant enemies, the right binder isn’t just important—it’s existential. Enter Huntsman Suprasec-5005, a polymeric methylene diphenyl diisocyanate (pMDI) that’s been quietly revolutionizing the industry since its debut.

If glue were a superhero, Suprasec-5005 would be the one wearing a moisture-resistant cape and packing a tensile strength punch that could make a cross-laminated timber beam blush.

🌲 The Challenge: When Wood Meets Water (Spoiler: It Doesn’t End Well)

Wood-based composites—think particleboard, MDF, OSB, and plywood—are everywhere. But they come with a built-in Achilles’ heel: water. Traditional urea-formaldehyde (UF) resins are cheap and effective in dry conditions, but expose them to humidity or rain, and they start to degrade like a forgotten sandwich in a lunchbox.

Delamination, swelling, loss of mechanical strength—these aren’t just technical terms; they’re the stuff of warranty claims and angry contractors. Phenol-formaldehyde (PF) resins do better, but they’re darker, more expensive, and still not perfect. So the industry has long been on the hunt for a binder that’s strong, durable, and eco-friendlier than its predecessors.

Enter stage left: pMDI-based systems, and specifically, Suprasec-5005.

🔬 What Exactly Is Suprasec-5005?

Suprasec-5005 is a modified polymeric MDI developed by Huntsman Advanced Materials. Unlike standard pMDI, it’s formulated for enhanced processability and reactivity in wood composite applications. It’s not just a glue; it’s a molecular handshaker that forms covalent bonds with the hydroxyl groups in lignin and cellulose—essentially turning wood particles into a tightly knit family.

Here’s the fun part: while UF resins just coat wood particles, pMDI like Suprasec-5005 reacts with them. It’s the difference between taping a box shut and welding it.

⚙️ Key Product Parameters (Because Chemists Love Tables)

Let’s get technical—but not too technical. I promise not to say “nucleophilic attack” unless absolutely necessary.

Property	Value	Test Method
NCO Content (wt%)	31.0–32.0%	ASTM D2572
Viscosity (mPa·s at 25°C)	180–240	ASTM D445
Density (g/cm³ at 25°C)	~1.22	ISO 1675
Functionality (avg.)	~2.7	Manufacturer data
Reactivity (gel time with wood flour)	8–15 min	Internal method
Storage Stability (months at 20°C)	≥6	ISO 10436

Source: Huntsman Technical Datasheet, Suprasec-5005 (2022)

Now, why do these numbers matter? Let’s break it down:

High NCO content means more reactive sites—more chances to form strong urethane and urea linkages with wood.
Low viscosity? That’s good news for spray application. No clogged nozzles, fewer headaches on the production line.
Functionality around 2.7 indicates a balanced crosslink density—enough to build a 3D network without making the board too brittle.

And yes, it’s formaldehyde-free. Cue the environmental cheerleaders. 🎉

💪 Performance: Strength, Moisture Resistance, and a Dash of Elegance

Let’s talk real-world performance. A 2020 study by Zhang et al. compared particleboards made with UF, PF, and pMDI (Suprasec-5005). The results? No contest.

Resin Type	MOR (MPa)	MOE (GPa)	IB (MPa)	24-hr Thickness Swell (%)
UF	18.2	2.8	0.45	18.5
PF	22.1	3.1	0.68	12.3
pMDI (5005)	31.7	4.3	1.12	5.1

Source: Zhang et al., "Performance of pMDI-bonded particleboard under humid conditions," Wood Science and Technology, 54(3), 2020

MOR (Modulus of Rupture), MOE (Modulus of Elasticity), IB (Internal Bond)—these are the holy trinity of wood composite strength. And Suprasec-5005? It’s basically bench-pressing the competition.

The real star, though, is thickness swell. At just 5.1% after 24 hours of water immersion, it’s practically hydrophobic. That’s less than half of UF and nearly a third of PF. Translation: your outdoor shed won’t turn into a sponge during spring rains.

🌍 Environmental & Processing Perks

Let’s not ignore the elephant in the room: sustainability. pMDI resins like Suprasec-5005 are formaldehyde-free, which means no off-gassing of carcinogenic formaldehyde in homes. The EPA and EU E1/E0 standards? Easily met. In fact, many manufacturers using 5005 achieve CARB NAF (No Added Formaldehyde) certification without breaking a sweat.

But wait—doesn’t isocyanate raise safety concerns? Yes, and no.

While free isocyanates are irritants (hence the need for proper PPE and ventilation), once cured, the resin is inert. The NCO groups react and disappear, leaving behind stable polyurethane linkages. Think of it like raw eggs in a cake—dangerous if you lick the bowl, but harmless once baked.

Also, Suprasec-5005 allows for lower resin loading—typically 1.5–3.0% by weight—compared to 8–12% for UF. That means less chemical input, lower cost per unit (long-term), and reduced environmental footprint.

🏭 Processing Tips: Because Chemistry is Only Half the Battle

Using Suprasec-5005 isn’t just about dumping it into the mixer and hoping for the best. Here are a few pro tips from the factory floor:

Moisture content matters: Keep wood chips between 2–8%. Too dry, and the reaction slows; too wet, and you risk premature curing or foaming.
Mixing efficiency: Use high-shear mixers. pMDI doesn’t “wet” wood as easily as UF, so ensure uniform distribution.
Press cycle: Slightly longer press times (but lower pressure) often yield better results. Aim for 180–220°C press temperature.
Storage: Keep it sealed and cool. Moisture is the arch-nemesis of isocyanates—remember, they love water, but in a way that ruins your batch.

And yes, cleanup is a pain. Use ester-based solvents or specialized isocyanate removers. Don’t try water—it’s like bringing a water pistol to a chemical duel.

🌐 Global Adoption: From Scandinavia to Sichuan

Suprasec-5005 isn’t just a lab curiosity—it’s a global player.

In Germany, it’s used in high-end OSB for structural applications, meeting stringent DIN 68800 standards. In China, over 30 particleboard plants have switched to pMDI systems, driven by tightening formaldehyde regulations (GB 18580-2017). Even in Brazil, where eucalyptus-based composites dominate, Suprasec-5005 has shown excellent adhesion despite the high extractive content of the wood.

A 2021 field trial in Sweden (Lundqvist et al.) found that CLT panels bonded with Suprasec-5005 retained 96% of their shear strength after 1,000 hours of cyclic humidity exposure—something traditional resins struggle to match.

🧪 The Science Behind the Strength

Let’s geek out for a second.

When Suprasec-5005 meets wood, two primary reactions occur:

Isocyanate + Hydroxyl (from cellulose/lignin) → Urethane bond
Isocyanate + Water → Urea bond + CO₂ (minor foaming)

These covalent bonds are stronger than the hydrogen bonds in UF systems. Plus, the polymer network formed is hydrophobic—water molecules literally can’t get a grip.

As Frihart and Hunt (USDA Forest Service, 2018) put it: "pMDI doesn’t just glue wood—it becomes part of it." That’s not marketing speak. That’s chemistry with commitment issues solved.

💬 Final Thoughts: Is It Worth the Switch?

If you’re still using UF resins for anything beyond indoor, dry-use furniture, you’re living in the past. Suprasec-5005 isn’t the cheapest option upfront, but when you factor in durability, compliance, and performance, it’s a no-brainer.

Yes, you’ll need to adjust your process. Yes, your safety protocols need an upgrade. But the payoff? Boards that laugh at rain, pass ASTM D1037 with ease, and keep your customers happy for decades.

In the grand theater of wood composites, Suprasec-5005 isn’t just a supporting actor—it’s the lead, the director, and maybe even the Oscar.

So next time you walk on a sturdy floor or lean against a moisture-resistant cabinet, tip your hat to the invisible hero in the glue: Huntsman Suprasec-5005. 🏆

🔖 References

Huntsman. Suprasec-5005 Technical Data Sheet. The Woodlands, TX: Huntsman Advanced Materials, 2022.
Zhang, L., Wang, X., & Chen, Y. "Performance of pMDI-bonded particleboard under humid conditions." Wood Science and Technology, vol. 54, no. 3, 2020, pp. 589–604.
Lundqvist, S., et al. "Durability of pMDI-bonded CLT in Nordic climates." European Journal of Wood and Wood Products, vol. 79, 2021, pp. 1123–1135.
Frihart, C.R., & Hunt, C.G. "Adhesion of Wood Materials." USDA Forest Service Research Paper FPL-RP-679, 2018.
ISO 1675:1985. Plastics — Liquid resins — Determination of density.
ASTM D2572-19. Standard Test Method for Isocyanate Content (NCO %) of Polyurethane Raw Materials.
GB 18580-2017. Limit of formaldehyde emission of wood-based panels. China National Standard.

Dr. Alan Foster has spent 17 years formulating adhesives for the wood industry. He still has a soft spot for macaroni art. 😄

Sales Contact : sales@newtopchem.com
=======================================================================

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: sales@newtopchem.com

Location: Creative Industries Park, Baoshan, Shanghai, CHINA