PROCESS FOR PRODUCING ACRYLONITRILE POLYMER

摘要

A process for producing an acrylonitrile polymer is disclosed. The process comprises initiating polymerization of a mixture comprising from 10 to 70% by weight of a polymerizable unsaturated monomer mixture containing at least 70 mol% of acrylonitrile, from 15 to 60% by weight of a good organic solvent and from 15 to 60% by weight of a poor solvent for an acrylonitrile polymer by using a radical intiator and, after the polymer is precipitated, adding at least one of said good organic solvent and said poor solvent to the polymerization system in a total amount of from 1 to 10 parts by weight of solvent(s) per part by weight of the polymerizable unsaturated monomer mixture. The resulting acrylonitrile polymer has a high degree of polymerization and a reduced viscosity of 2.0 or higher.