Patent ID: 6451430
Filing Date: 2002-09-17
Classification: B32B,C08G,Y10T

Abstract:
A method of preparing a composite foam structure of a rigid polyurethane foam core material and a bonded layer of cured polyester resin composition, which method comprises:a) providing a rigid polyurethane foam material, prepared by the reaction of a foamable composition which comprises: a polyisocyanate; a polyol; a catalyst; a blowing agent; and an organic additive, which organic additive is selected from the group consisting of: i) an additive monomer having one or more hydroxyl groups; and ii) an additive prepolymer prepared by the reaction of the hydroxyl groups of the additive monomer with a stoichiometric amount or excess amount of a polyisocyanate; the additive monomer and additive prepolymer having ethylenically unsaturated groups which remain unreacted in the foamable composition and resulting prepared rigid foam, the ethylenically unsaturated groups selected from the group consisting of: allyl groups; acrylic groups; and combinations thereof; b) applying a layer of an unsaturated polyester resin composition which comprises an ethylenically unsaturated polyester resin, a monomer, and a curing agent to one or both surfaces of the foam material; and c) curing the polyester resin composition, to bond chemically the contacting surfaces of the polyester resin layer and the rigid foam material, by the polymerization reaction of the ethylenically unsaturated groups of the foam material with the polyester resin layer.