Ready-to-use Aliphatic Polyisocyanates

Polyurethanes adhesives are made from macromolecules or polymers formed by the reaction between a polyisocyanate and another polymer - commonly known as a polyol - that contains OH groups. When selecting an aliphatic polyisocyanate for your adhesive formulation, two main categories can be distinguished: two-component (or 2K) and heat-activated, one-component (or 1K). 2K polyurethane adhesives Two-component systems consist of a polyisocyanate and a polyol that are mixed just prior to application and cure at room temperature. Therefore, 2K polyurethane adhesives are used :    - on substrates sensitive to heat (plastics, wood, cars....),    - on objects too big to be stoved (trains, airplanes, bridges...). 1K polyurethane adhesives One-component PUs are similar materials to the previous one, except that a blocked isocyanate is used to provide a storage stable one-pack formulations containing the polyol. After application of the adhesive on the substrate and during stoving at elevated temperature, the isocyanate is de-blocked and then it reacts with the polyol to form the PU network.