| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a vinyl chloride resin pipe which is excellent in impact resistance and mechanical strength and does not shrink at temperatures close to its Vicat softening point. SOLUTION: In the method for producing the vinyl chloride resin pipe which is molded from a vinyl chloride resin composition mainly containing a vinyl chloride resin 800-5,000 in average molecular weight which is obtained by graft copolymerizing 97-90 wt.% of vinyl chloride monomer on 3-10 wt.% of an acrylic copolymer obtained by copolymerizing 100 pts.wt. of acrylic monomer containing at least 80 wt.% of an alkyl (meth)acrylate the glass transition temperature of the home-polymer of which is lower than -20 deg.C with 0.1-10 wt.% of a poly- functional monomer, the temperature of the outer surface of the pipe is adjusted between the glass transition temperature of the composition (Tg) and (Tg+40 deg.C), the temperature of the inner surface is adjusted between (Tg+60 deg.C) and (Tg+100 deg.C) to form a temperature inclination in the thickness direction of the pipe, and the pipe is stretched in the circumferential direction in a draw ratio of 1.3-2.5 and in the axial direction in a raw ratio of 1.1-2.5.
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