EXTRUDED SYNTHETIC RESIN FOAM AND ITS MANUFACTURING METHOD

摘要

An extruded synthetic resin foam comprises a cell structure of substantially two different cell sizes, the smaller size being not more than about 0.25mm while the other size is from about 0.4 to about lmm. The cells are dispersed in an island in the sea manner. A foam such as a styrenic foam is produced by forming a mixture of synthetic resin, a fine mineral powder having hydroxyl groups, and a cell controlling agent,incorporating a volatile foaming agent and extruding the mixture to form a foam. The powder has a particle size of not more than 1000nm and may be a silica having silanol groups.