Silane-modified polymerSMP

A flexible material applied to joints and interfaces to exclude water, air or other media while accommodating movement between the parts, in contrast to an adhesive whose primary job is to transfer load. Silicone, polyurethane, polysulphide and silane-modified polymer chemistries dominate construction and industrial sealing.

A curing mechanism in which a one-part adhesive, sealant or coating reacts with atmospheric humidity, hardening from the exposed surface inwards. One-part polyurethanes, silicones and silane-modified polymers cure this way; cure through thick sections is slow and depends on humidity and temperature.

A polymer family with a backbone of alternating silicon and oxygen atoms, giving outstanding resistance to weathering, UV and temperature extremes while remaining flexible. Silicones are used as sealants, gaskets, mould-making rubbers and liquid-applied roof coatings, and most sealant grades cure at room temperature with atmospheric moisture.

A broad polymer family formed by reacting isocyanates with polyols, producing everything from soft foams and elastomers to rigid plastics, adhesives, sealants and coatings. In construction and roofing it appears as insulation foam, liquid-applied waterproofing membranes and flexible adhesives, and many one-part grades cure with ambient moisture.