| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polyacetal resin composition excellent in blow moldability, having good appearance, high in impact resistance, and useful for e.g. automotive fuel tanks, comprising two kinds of polyacetal with specific shear viscosity ratio. SOLUTION: This resin composition comprises (A) 80-99.5wt.% of a branched or crosslinked polyacetal and (B) 20-0.5wt.% of a linear high-molecular weight polyacetal with the shear viscosity ratio for the components A and B satisfying the relationship: 1.0<=ηL/ηB<=3.0 (ηL is the shear viscosity of the component B;ηB is the shear viscosity of the component A; determined at 190 deg.C under a shear rate of 1.2×10<3> s<-1> with a capillary L/D of 10). It is preferable thatηL andηB are 500-1,300 Pa.s and 350-700 Pa.s, respectively, and the component A is obtained pref. by copolymerization between trioxane as the main monomer, a cyclic ether or cyclic formal as comonomer and a compound bearing two or more cyclic ether or cyclic formal groups in the presence of a cationic active catalyst. |
