Modified Silane Adhesive Sealants

Modified silanes (MS) are odourless, non-corrosive and do not contain isocyanates, solvents, silicones or PVC. They are normally available as single-component adhesive sealants (although two-part systems are also available) and require atmospheric moisture during the cure cycle. 

The slow cure cycle of MS adhesive sealants has been addressed by some manufacturers and two-part (mix-in-the-nozzle) versions are increasingly being made available. The cure time on these products is typically less than 15 minutes. 

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Two-Component Sealants.Two-component butyl sealants are room temperature vulcanized materials. Low in moisture vapor transmission and easy working because of low molecular weight and semi-liquid form, these sealants are filled with calcium carbonate and titanium dioxide, plasticized with polybutene, and may be modified with epoxy and silane adhesion promoters. The cure system is p-qui-none dioxime activated with a peroxide. 

Epoxies, poljmrethanes, two-part acrylics and the adhesive/sealant products (silicones, and modified silanes) all have excellent gap-filling capabilities and some of these products will offer excellent resistance to impact loading and peel loads. 

Some adhesives - often the higher viscosity epoxies, two-part acrylics and certainly the silicone and modified silane sealants - have good wet strength and this property can be useful for applications where an initial grab strength is useful. 

Apart from the development of polyurethane adhesives and sealants with isocyanate reactive groups, a new type of silane-terminated polymer adhesive has been developed called Polyurethane (PUR)-Hybrids. They and modified silicones (MS) and provide the benefits of ... 

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