zweikomponentiger polyurethane adhesive for wood materials

摘要

A two-component polyurethane adhesive for adhesively bonding wooden materials based on a polyol component A consisting of a) 10 to 98 wt. % of at least one oleochemical polyol, b) 1 to 7.5 wt. % of at least one diol having a hydroxyl value of 400 to 2000 and c) 1 to 7.5 wt. % of at least one tri-, tetra- or pentafunctional polyol having a hydroxyl value of 200 to 2000, the wt. % of each of a), b) and c) is based on the whole of the polyol mixture, and a polyisocyanate component B), wherein the NCO/OH ratio of components A) and B) is within the range of 1.5 to 0.9. The addition to the polyol component of 0 to 60 wt. %, based on the total weight of the polyol mixture, of a homogeneously dissolved resin, brings about a sharp increase in the adhesive strength. The adhesive maintains its strength even after boiling for 24 hours and drying for 7 days at 60° C. The adhesive is highly suitable for loadbearing structural members made of wood.