Fosroc Nitoseal MS Hybrid Sealants



For too long, applicators have put up with messy, stringing polyurethane sealants. But it doesn’t have to be that way: sealant technology has moved on with Fosroc’s polyurethane hybrid sealants, Nitoseal MS250 and MS400.

Nitoseal MS: the best of polyurethanes and silicones combined

Nitoseal MS sealants are based on silyl modified polymers, also known as hybrid polyurethanes or MS polymers.

Embracing Fosroc ANZ’s proven Duraflex technology, our Nitoseal MS250 and MS400 sealants combine the benefits of polyurethanes and silicones. They offer the weathering and adhesion performance of silicones, with the toughness of polyurethanes. Unlike polyurethanes, MS sealants do not contain isocyanate.

Nitoseal MS250 is our general construction sealant while Nitoseal MS400 is for trafficable joints.

“Nitoseal MS sealants combine a polyurethane backbone with silicone functional groups,” explains Martin Venn, Fosroc ANZ’s Technical Support Manager. “They are moisture tolerant and won’t gas or bubble from excessive moisture in the environment, which is a big advantage compared to polyurethanes. They also offer better long-term UV stability and are easier to apply.”

The future of sealants in colour

Fosroc ANZ is backing Nitoseal MS as the new go-to sealant for the construction industry. That’s why we are manufacturing Nitoseal MS250 in 11 Australian Standard colours and offering colour matching for both products.

Colin Picton, our Product Segment Specialist for Waterproofing & Sealants, explains: “Polyurethane sealants are considered the ‘standard’ in Australia, almost out of habit. But in Europe, for example, hybrids really drive the market.

This is based on performance but also because the industry is concerned about the health impacts of isocyanate, including skin and eye irritations and occupational asthma.

“Fosroc ANZ offers PU-only sealants but we believe the real value is in the MS hybrid range. You are getting the best performance but also a quicker, easier and safer sealing experience for the applicator.”

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