High-modulus, flexible urethane coating and method of preparation

摘要

A high-modulus, solid urethane spray coating is prepared by spraying onto a substrate equal volumes of an A-side and a B-side mixture together, the A side comprising 100 parts of a prepolymer prepared by reacting a polyether triol with a low-functionality MDI, and the B side comprising from about 5 to 40 parts of a butane diol and 60 to 95 parts of a polyether triol, and a catalyst system which comprises a tetravalent tin catalyst in combination with an acid-blocked amine catalyst.