Dual component polyurethane compounds on the basis of renewable resources, particularly suitable for use as tough elastic adhesives with adjustable hydrolytic degradability

摘要

Two-component polyurethane composition comprises polyol component (K1) and a polyisocyanate component (K2). The polyol component (K1) comprises castor oil (A1) and 1,2,3-propanetriol (A2). The polyisocyanate component (K2) comprises at least one aromatic polyisocyanate (B1). The ratio of wt.% of (A1/A2) is 4-50. The ratio of all isocyanate groups of the aromatic polyisocyanate (B1) and all hydroxy groups is the sum of (A1+A2) i.e. 1.15:1-0.85:1. The sum of all hydroxy-groups of (A1+A2) is >= 93%, preferably >= 99%. Independent claims are also included for: (1) a bonding method comprising mixing the polyol component (K1) and the polyisocyanate component (K2) of the two-component polyurethane composition, applying the mixed polyurethane composition to at least one of the substrate surfaces to be adhered, adding within the open time and curing the polyurethane composition; and (2) an adhesively bonded article which has been bonded by the above method.