Process for preparing chlorinated polymer or copolymer of vinyl chloride

摘要

A process for preparing a chlorinated polymer or copolymer of vinyl chloride which comprises varying the amount of ultraviolet rays irradiated to a unit amount of the polymer or copolymer to control the reaction rate within the range from 0.75-0.25 mole/hour/kilogram of the polymer or copolymer until the rate of substitution of chlorine attains at least 1.6 moles/kilogram of the polymer or copolymer, the polymer or copolymer being chlorinated in an aqueous suspension under irradiation of ultraviolet rays. The polymers so produced have excellent thermal stability and excellent processability.