Radiation-induced copolymerization of phenylvinyl alkyl ethers and maleic anhydride

Alternating copolymers of phenylvinyl ethyl ether (I) and phenylvinyl sec-butyl ether (II) with maleic anhydride (MAn) were prepared in bulk or in benzene solution by high-energy irradiation at dose rates of 42, 160, and 540 Gy/h, respectively. The overall energies of activation in copolymerization of I and II with MAn were 15.5 and 18.8 kJ/mol, respectively. The reaction proceeds by the free-radical mechanism and was found to be largely dependent on the bulkiness of the alkyl group. In the copolymerization of I and MAn, the molecular weight increases with conversion. By applying the model described by Shirota and co-workers, it was established that participation of charge-transfer-complex monomers increases with the increase of the total monomer concentration and with the bulkiness of the alkyl group in electron donor monomer.