PURPOSE: To enable stabilised extrusion processing of vinylidene chloride resin (VDC resin) without using a plasticiser, by a method wherein a specific quantity of a mixture of a styrene acrylonitrile copolymer resin and uncured epoxy resin is added to vinylidene chloride resin and extruded with a screw extruding machine.

CONSTITUTION: A 0.5-40 pts.wt. mixture of AS resin and uncured epoxy resin is added to 100 pts.wt. VCD resin and they are extruded with a screw extruding machine. A mixture ratio of the uncured epoxy resin and AS resin is that the uncured epoxy resin falls within a range of R-60wt.% and the AS resin falls within a range of (100-R)-40wt.% in the mixture of the uncured epoxy resin and AS resin. However, the R is the value to be obtained by the following formula of R=0.03×E where the E is an epoxy equivalent of the uncured epoxy resin. The VCD resin consisting mainly of vinylidene chloride is of thermoplastic resin comprised of vinylidene copolymer obtained by copolymerizing the vinylidene chloride and a small quantity of monomer copolymerizable with the vinylidene chloride, for example, vinyl chloride or alkylacrylate or alkylmethacrylate.