Copolymers of Bromine-containing Monomers 8. Copolymers of Acrylonitrile with some Brominated Phenyl Methacrylate

Acrylonitrile was free radical copolymerized with 2,4,6-tribromophenyl methacrylate of pentabromophenyl methacrylate in aqueous emulsion or dimethylformamide solutions.The thermal and flammability characteristics of the resulting polymers were investigated.The reactivity ratios of the monomers and the initial rates for homopolymerization and copolymerization reactions were determined.The monomer reactivity ratios were found to depend slightly on the reaction medium and the reaction rates are in the order acrylonitrile > pentabromophenyl methacrylate > tribromophenyl methacrylate.Thermal stability determined from TGA and DTG measurements showed that poly(2,4,6-tribromophenyl methacrylate) and its acrylonitrile copolymers were thermally more stable than the poly(pentabromophenyl methacrylate) and its acrylonitrile copolymers, though the latter showed better flame-retardant properties as was demonstrated by Iimiting oxygen index measurements.