Improvements in or modification of the process for the catalytic polymerisation of acrylonitrile

摘要

The process of the parent Specification is modified by adding to the polymerization mixture at least 1.7 per cent of sulphur dioxide, calculated on acrylonitrile, the molar amount of sulphur dioxide being greater than the molar amount of catalyst; under these conditions the molecular weight of the polymeric product is independent of the concentration of sulphur dioxide. In an example acrylonitrile is polymerized in a medium consisting of heptane and water, in the presence of ammonium persulphate as a catalyst and sulphur dioxide. Specification 744,206 also is referred to.