Polymeric foams

摘要

A method the preparation of rigid foams by reacting an organic polyisocyanate with an isocyanate-reactive material in the presence of a blowing promoter characterised in that the isocyanate-reactive material comprises at least one isocyanate-reactive cyclic carbonate or isocyanate-reactive cyclic urea, the reaction being performed in the presence of an inert insoluble organic liquid which is present as the dispersed phase of an emulsion or a microemulsion, and in the presence of a metal salt catalyst.