A novel process for the chlorination of polymers in solution

A new uniform process for the solution chlorination of PVC, PE, and natural rubber has been developed with initiation by γ-irradiation or radical initiators (azocompounds). The solvent used is dichloromethane instead of the industrially used tetrachloroethane or tetrachloromethane. The reaction is carried out in an autoclave with stirrer at temperatures between 70 and 100°C and pressures from 4 to 7 bar. As a result of the simultaneous chlorination of the solvent, trichloromethane is formed and only less than 1 wt.-% tetrachloromethane. Characterization of the chlorinated polymers by DSC and NMR measurements showed no differences to conventionally chlorinated products.