Hard foam

Abstract

A hard foam formed from a carboxylic acid ester-based polymer having a ring structure, the hard foam being obtained by heating the carboxylic acid ester-based polymer having a ring structure to generate a gaseous organic acid from the carboxylic acid ester-based polymer, and foaming the heated carboxylic acid ester-based polymer with the gaseous organic acid, and a method for producing the same. The hard foam can be used as various heat insulating materials, various vibration isolators, various acoustic materials, various soundproof materials and the like. Therefore, the hard foam is expected to be used for automobile component materials, materials for airplanes, materials for the space field, materials for industries, materials for medical assistance, and the like.

Dependencies are inferred from the claim text.