THE THERMAL-DEGRADATION OF POLYMETHACRYLONITRILE WITH DIFFERENT END-GROUPS

Polymethacrylonitrile (PMAN) was prepared by bulk, solution and precip itation polymerization. The thermal stability of the polymer, which is affected by the structure of the chain end groups, was studied by non -isothermal thermogravimetry (TG). On the basis of the differential TG curves of samples prepared by polymerization in the presence of chlor inated solvents, it may be concluded that, in addition to end-chain an d random main chain scission initiated depolymerization, hydrogen chlo ride evolution also occurs during the thermal degradation of PMAN.