Vinyl chloride polymers.

摘要

The invention relates to a process for preparing vinyl chloride polymers by suspension polymerization in a polymerization reactor of vinyl chloride, optionally in combination with at most 30% (wt) of one or more monomers copolymerizable therewith, monomer-soluble, radical-forming initiators and optionally in the presence of primary suspending agents. The improvement comprises the addition of 0.01 - 0.5 part by weight of at least one polyvinyl ester with an average degree of solvolysis lower than 70 moles % per 100 parts by weight of the starting monomer to the polymerization reactor before or during this polymerization, which polyvinyl ester is chosen from the polymeric vinyl esters of aliphatic and/or aromatic carboxylic acids with 3 - 20 C-atoms per molecule.