STYRENIC POLYMER FOAM WITH COMONOMER CONTENT

摘要

Disclosed is a process for making a styrenic polymer foam structure, comprising: a) heating a styrenic polymer material comprising greater than 50 percent by weight styrenic monomeric units and 0.1 to 40 percent by weight of oxygen-containing units based upon the total weight of the styrenic polymer material to form a melt polymer material; and b) incorporating into the melt polymer material a blowing agent comprising 5 weight percent or more carbon dioxide based upon the total weight of the blowing agent. Further disclosed is a foam structure obtainable according to the above process. The oxygen-containing comonomer content in the styrenic polymer material enables process operating pressures to be significantly reduced when using carbon dioxide as a blowing agent compared to a styrenic polymer material without comonomer content. The foam structure formed is of low density and of good quality.