| 摘要 |
PCT No. PCT/JP96/01933 Sec. 371 Date Mar. 7, 1997 Sec. 102(e) Date Mar. 7, 1997 PCT Filed Jul. 11, 1996 PCT Pub. No. WO97/03100 PCT Pub. Date Jan. 30, 1997In preparing a polyacetal copolymer through copolymerization of trioxane as the principal monomer with a cyclic ether or cyclic formal having at least one carbon-carbon bond as the comonomer, 0.05 to 100 ppm (on the weight basis), based on the total amount of the monomers, of a heteropoly-acid or an acidic salt thereof is used as a polymerization catalyst, and a liquid mixture preliminarily prepared by mixing at least part or the whole of the comonomer with the polymerization catalyst is added to trioxane to effect copolymerization. According to such the process, the polymerization yield and the degree of polymerization (molecular weight) are enhanced, and a polyacetal copolymer having an improved stability can be obtained.
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