Extruded foam slabstock with a high open cell content, used for production of vacuum panels, is based on a mixture of styrene polymer and polymethyl methacrylate.

摘要

Extruded foam slabs based on styrene polymer, with an open cell content of more than 80%, in which the thermoplastic matrix contains (A) 90-50 wt% styrene polymer and (B) 10-50 wt% polymethyl methacrylate. An Independent claim is also included for a process for the production of these foam slabs by extrusion of a thermoplastic melt containing (A), (B) and optionally a thermoplastic (C) with a glass transition point (Tg) above 140 deg C, together with 1-15 wt% volatile blowing agent (based on A + B + C) and optionally other additives, at 110-150 deg C.