Radiation-induced degradation of polymethacrylonitrile in solution

Radiation-induced degradation of polymethacrylonitrile (PMAN) was studied in dimethylformamide (DMF) and acetone solutions. Random scission of the polymer chain was confirmed by GPC measurements. The degradation of PMAN was found to occur more rapidly in DMF than in acetone. The overall activation energy of the degradation in DMF was estimated to be 6.1 kcal/mol in the temperature range from 0 to 500C. When the irradiation was performed in the presence of hydroquinone, about 50% of the main-chain scission was suppressed, whereas the degradation was scarcely affected by the addition of triethylamine. The results obtained indicate that the contribution of radical species is important in the degradation of the present system. (author)