Isocyanate terminated quasi-prepolymers useful for preparing urethane-group-containing polyisocyanurate foams having low friability

摘要

Flame retardant intumescent polyisocyanurate rigid foams are prepared by trimerizing isocyanate-terminated quasi-prepolymers containing predominately urethane linkages prepared by reacting an organic polyisocyanate with polyester polyols derived from the transesterification of dimethyl terephthalate process residue. The solvent blown rigid polyisocyanurate foams have exceptionally low friability.