PRODUCTION METHOD FOR OXYMETHYLENE COPOLYMER

摘要

A method for the continuous production, at high polymerization yield, of an oxymethylene copolymer having improved thermal stability and formaldehyde emission, while maintaining toughness and rigidity, is provided. Provided is a production method for oxymethylene copolymer, including: a step of carrying out a copolymerization reaction of trioxane and 1,3-dioxolane in an amount of 0.9-2.4 mass % with respect to the trioxane, in the presence of 0.001-0.007 mol % of boron trifluoride and 0.006-2.0 mass % of a sterically hindered phenol with respect to the trioxane; and a step of adding a polymerization terminator to the reaction system at the point in time that the polymerization yield of the copolymerization reaction has reached 92% or above, to terminate polymerization.

主权项

1. A process for producing an oxymethylene copolymer comprising the steps of:
performing copolymerization reaction of raw material monomers including trioxane and 0.9 to 2.4% by mass of 1,3-dioxolane relative to the trioxane in the presence of 0.001 to 0.007% by mole of boron trifluoride relative to the trioxane and 0.006 to 2.0% by mass of a sterically hindered phenol relative to the trioxane; and terminating the copolymerization by adding a polymerization terminator to the reaction system at a point in time when the copolymerization reaction gives a polymerization yield of 92% or more.