Solid heat triggered compositions capable of forming a polyurethane foam

Claim 1

A FREE-FLOWING COMPOSITION THAT IS STABLE AND NONREACTIVE AT ROOM TEMPERATURE AND IS CAPABLE UPON BEING HEATED TO AN ELEVATED TEMPERATURE SUBSTANTIALLY IN EXCESS OF ROOM TEMPERATURE OF MELTING, FUSING, AND REACTING TO FORM A PLASTIC FOAM COMPOSITION WHICH COMPRISES A MIXTURE OF FINELY DIVIDED PARTICLES OF A COMMINUTED SOLID THERMOPLASTIC RESINOUS MATERIAL CONTAINING A PLURALITY OF UNREACTED ISOCYANATE GROUPS, WHICH IS THE REACTION PRODUCT OF AN ORGANIC DIISOCYANATE AND A POLYOL SELECTED FROM THE GROUP CONSISTING OF A DIOL, A POLYOXYPROPYLENE DERIVATIVE OF TRIMETHYLOL PROPANE, A POLYOXYPROPYLENE DERIVATIVE OF PENTAERYTHRITOL AND A POLYOXYPROPYLENE DERIVATIVE OF SORBITOL, CHARACTERIZED BY A MELTING POINT BETWEEN 30* AND 70*C., AND OF FINELY DIVIDED PARTICLES OF A MATERIAL WHICH RELEASES WATER AT A TEMPERATURE IN EXCESS OF THE MELTING POINT OF SAID THERMOPLASTIC RESINOUS MATERIAL AND BELOW THE FOAM-FORMING REACTION TEMPERATURE.