CRYSTALLINE, GRINDABLE POLYURETHANE PREPOLYMERS

摘要

A crystalline grindable end-blocked prepolymer useful in providing a polyurethane elastomer having a 100% modulus less than approximately 250 psi, tensile of 3500 to 6500 psi, and less than 30% initial tensile set, said prepolymer being the product of reacting an organic polyisocyanate, a long chain crystalline diol having an average molecular weight of approximately 500 to 5000, a polyhydroxy cross-linking agent, and an end-blocking agent.