PRODUCTION OF VINYL CHLORIDE RESIN MOLDED PRODUCT

PROBLEM TO BE SOLVED: To perform mixing and extrusion molding at a low temp. without imparting heat history and to obtain excellent surface appearance by connecting at least two gear pumps and introducing a vinyl chloride resin compsn. into the gear pumps in a powdery or non-melted state under pressure to subject the same to shearing mixing in the gear pumps before performing extrusion molding directly. SOLUTION: A powdery compd. such as a hard vinyl chloride resin compsn. or the like is introduced into gear pumps 10 under pressure through a cylinder 3 and a screw 6 set to predetermined temp. This compd. is introduced into the grooves of a pair of gears 17 to be rotated along the housing of the gear pumps 10 while adjusted to constant temp. to be mixed by the shearing force applied at the discharge ports of the respective gear pumps by the meshing of paired gears 17, 18 to be extruded toward an extrusion die housing 22. The pressure in a die rises and resin temp. also rises at the same time. Since two or more gear pumps are connected, a chance imparting shearing force to the resin compsn. increases and the kneading effect proportional to the number of the gear pumps is imparted. The resin compsn. can be molded at low temp. without being thermally decomposed to obtain excellent appearance and physical properties.