PVC PVC ENHANCED PROCESS FOR THE PRODUCTION OF EXPANDED PVC AND PLATIC MATERIALS BASED ON EXPANDED PVC OBTAINED THEREWITH

摘要

A process for the production of an expanded PVC of the type comprising heating a lump (13) of a polymer mixture in a closed mold, said process comprising the steps of: (a) Controlling the foaming of the lumps (13) due to a hot molding process in an environment with a certain volume, the control being performed by controlling the microcels (20) of the blowing gas in the lumps (13) (16) of a compressible material suitable for retracting from an initial form (A) having a larger volume to a form (B) having a smaller volume under the action of the pressure produced by the formation of the polymer mixture In the agglomerates (13) of the agglomerates (13); And (b) the step of foaming the microparticles (16) contained in the mass of the molded foamed material into an initial form (A) having a larger volume in form (B), and the density of the foamed material obtained thereby, Characterized in that it is determined by the simultaneous presence of microcells (20) of foam gas in said mass of material (13c) and said microparticles (16) of a larger volume (A) having a larger volume. With respect to the prior art for the production of foam plastic materials, the process of the present invention not only prevents the formation of melt loss during the molding process, even when using a much smaller amount than the amount of foaming agent used in current processes of this type A foamed PVC having a desired density value can be obtained.