CLOSED CELL POLYMER FOAM

摘要

A closed-cell polymer foam having a density of less than 100 kg.m<-3> is described. The cells in the foam contain a foam blowing agent comprising (a) a blend of two or more hydrofluorocarbons, (b) a blend comprising a carbon dioxide and one or more hydrofluorocarbons or (c) a blend comprising dimethyl ether and one or more hydrofluorocarbons, and the polymer is a blend comprising at least 50 % by weight of an olefinic polymer(s) and up to 50 % by weight of a polar polymer(s) having a lower molecular weight than the olefinic polymer which when in the heat plasticised state is able to dissolve the foam blowing agent. A process for preparing the foam is also described.