MACRORADICAL FORMATION AND LOSS KINETICS IN VARIOUS POLYMERS UNDER CONDITIONS OF PLASTIC-FLOW AT HIGH-PRESSURES

The laws of radical formation kinetics in poly(ethylene), poly(propyle ne), poly(vinyl pyrrolidone), poly(vinyl chloride), poly(styrene),poly (carbonate), and poly(imide) at high pressures were studied under the plastic flow conditions in Bridgman's anvils. A critical rotation angl e was observed at which the radical concentration attains a stationary level. The rates of mechanochemical activation and loss of macroradic als were determined. It was demonstrated that plastic deformation at h igh pressures leads to a sharp increase in the macroradical loss rate constant compared to that for the isothermal loss at a normal pressure .