| 摘要 |
PROBLEM TO BE SOLVED: To provide a pipe joint made of vinyl chloride rein having both good shock resistance and good long term durability. SOLUTION: A copolymer of alkyl(metha)acrylate having under -60 deg.C homopolymer of Tg and a multifunctional monomer is graft copolymerized with a monomer composition composed of (mtha)acrylate having over -60 deg.C homopolymer of Tg and a multifunctional monomer to obtain an acrylic copolymer. 1 to 20 wt.% resin particles (a) formed of the acrylic copolymer and having the mean particle diameter of under 0.15μm is graft copolymerized with 99 to 80 wt.% vinyl chloride monomer to obtain vinyl chloride resin. An impact modifier (b) having the mean particle diameter of 0.20μm or more is added to the vinyl chloride resin having the average degree of polymerization of 900 to 1500 in a vinyl chloride resin part to form a vinyl chloride resin composition wherein (a)/(b) is at the weight ratio of 30/70 to 95/5. The vinyl chloride resin composition has Izod impact strength of 15 kJ/m2 at 0 deg.C, and in repeated tensile fatigue test at a temperature of 23 deg.C, at a frequency of 5 Hz and with applied stress of 0 to 20 Mpa, the count of tension to fracture is 80000 or more. This pipe joint is made of the above vinyl chloride resin composition.
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