Influence of pressure on the radical polymerization of acrylonitrile in dimethylformamide solution

Abstract

1. The rate of homogeneous radical polymerization of acrylonitrile in dimethylformamide at 50°, in contrast to the heterogeneous radical polymerization of acrylonitrile, quadruples when the pressure is raised from atmospheric to 2000 kg/cm2, while the average molecular weight of the polymer increases by 50%. 2. The comparatively small increase in the molecular weight of the polymer at 2000 kg/cm2 is evidently due to the fact that a substantial role in the system studied is played by the reaction of chain transfer through dimethylformamide, and this reaction is accelerated by pressure almost to the same degree as the reaction of chain growth.