| abstract |
(57) [PROBLEMS] To provide a polyacetal copolymer with a simple process, a high yield, and an excellent quality such as thermal stability. SOLUTION: In producing a polyacetal copolymer by copolymerization with trioxane as a main monomer and a cyclic ether or cyclic formal having at least one carbon-carbon bond as a comonomer, as a polymerization catalyst, (A) a heteropoly acid or an acid salt thereof, at least one nonvolatile protonic acid catalyst selected from an isopoly acid or an acid salt thereof, and (B) at least one polymerization catalyst selected from a perfluoroalkylsulfonic acid or a derivative thereof. Are used together for copolymerization, and then a deactivator for the catalyst is added for deactivation. |