POLYISOCYANURATE RIGID FOAMS AND PROCESSES FOR THEIR PRODUCTION AND USE

摘要

PIR rigid foams are produced from a polyisocyanate component and a polyol component that includes at least one polyester polyol and at least one polyether polyol. The polyisocyanate and polyol components are reacted in amounts such that the volume ratio of polyisocyanate component to polyol component is from 100:100 to 100:110 and the index is from 100 to 400. These foams are characterized by good adhesion to a substrate and impermeability to water vapor. The foams are generally produced by a casting process and are particularly useful as an insulating material for containers and tanks.