Thermoplastic corrugation-free foam

摘要

A thermoplastic foam comprising a styrenic polymer, and a blowing agent consisting of 100% carbon dioxide. The thermoplastic foam has no visible corrugation, or preferably none at all, and has an average cell size of 0.20 mm to 0.30 mm. The average cell size is preferably less than 0.25mm. The foam may be formed by extrusion using the device of figure 3.