METHOD FOR POLYMERIZING VINYL CHLORIDE

摘要

The formation of a polymer crust on the surfaces of a polymerisation reactor in which vinyl chloride is polymerised alone or together with other ethylenically unsaturated monomers is avoided completely or virtually completely by adding a crust preventer to the polymerisation mixture. This additive comprises one or more substances from the following list: iodine, iodine compounds, bromine, bromine compounds, thiocyanates, isothiocyanates, phytic acid and derivatives thereof, and reducing organic compounds. In addition, the reactor surfaces can be treated with polar organic compounds or an organic dye.