FOAMABLE POLYMERISATE BASED ON POLYPHENYLENE OXIDE AND A VINYLAROMATIC COMPOUND, METHOD FOR THE PRODUCTION AND USE THEREOF

摘要

Hitherto, heat distortion resistant foams based on polyphenylene oxide and a vinylaromatic compound have been prepared by polymerising the vinylaromatic compound in the presence of polyphenylene oxide. The finished polymer blend is then granulated, mixed with the blowing agent in the extruder and subsequently expanded. This process is complex and expensive. In the process according to the invention, the foamable polymer is prepared in a one-step process, ie. the mixing with the blowing agent takes place during the polymerisation. In addition, caking on the reactor walls is prevented by adding the starting materials in a specific sequence, which results in an increase in yield. Expansion then follows. The foams produced from the foamable polymers are preferably employed for thermal insulation.