Foamability of Thermoplastic Vulcanizates (TPVs) with Carbon Dioxide and Nitrogen

The foamability of thermoplastic vulcanizate (TPV) has been investigated in a customized foaming system using carbon dioxide (CO ₂ ) and nitrogen (N ₂ ) as a physical blowing agent. TPV or dynamic vulcanizate is a special class of thermoplastic elastomer that is produced by technological blending of a rubber and a thermoplastic simultaneously. The rubbery part was dynamically cured in a thermoplastic matrix. The influence of blowing agent content and the processing conditions on the expansion behaviour, the cell-number density and the foam structure are discussed. The TPV foam with N ₂ produced a uniform and fine cell structure with a smooth surface, indicating that N ₂ could be a very good physical blowing agent for TPV material.