| 摘要 |
A process for producing a polyacetal copolymer, the process making catalyst deactivation easy and efficient, requiring no cleaning step, merely requiring simple equipment and simple operation techniques, and rendering a high polymerization yield and high quality possible. In the invention, trioxane as a major monomer (a) is copolymerized with one or more comonomers (b) that are a cyclic ether and/or cyclic formal having at least one carbon-carbon bond, using a nonvolatile protonic acid as a polymerization catalyst (c) at a polymerization environment temperature of 100°C or lower until the conversion reaches 50% and thereafter at a polymerization environment temperature in the range of 115°C to 140°C. This process includes: a crushing step in which a dry-process crusher is used to obtain a crude polyacetal copolymer (d2) crushed to such a degree that when the crude copolymer (d2) is screened with a sieve having an opening size of 11.2 mm, 90 parts by weight or more thereof passes therethrough; and a deactivation step in which a basic compound (e) is added to the ingredient (d2) and the mixture is melt-kneaded to thereby deactivate the ingredient (c). |
