Polymerization of methacrylonitrile with potassium in ammonia

The molecular weight of polymethacrylonitrile obtained in the system lithiumammonia-methacrylonitrile at −75° increased with decreasing concentrations of lithium and increasing concentrations of methacrylonitrile, and in addition was found to be proportional to [methacrylonitrile]/[lithium]. On the basis of this and additional evidence, a one-electron transfer from lithium to methacrylonitrile to give an anion radical is postulated. In addition, the structure of the colored polymer obtained is discussed on the basis of the infrared spectra.