Karla Sarić

Copolymers of Styrene with Some Brominated Acrylates

Abstract Styrene was copolymerized with 2,3-dibromopropyl acrylate, 2,4,6-tribromophenyl acrylate, or pentabromophenyl acrylate in either aqueous emulsion, dimethylformamide, or benzene solutions with a free radical initiator, and the thermal and flammability properties of the resulting polymers are described. The reactivity ratios of the monomers and the initial reaction rates for homopolymerization and copolymerization reactions in benzene were established. The monomer reactivity ratios were found to depend slightly on the reaction medium. The reaction rates for both homopolymerizations and copolymerizations increased in the order styrene < 2,3-dibromopropyl acrylate < 2,4,6-tribromophenyl acrylate < pentabromoacrylate. The thermal stability of the polymers, determined from TGA and DTG measurements, showed that poly(2,4,6-trtbromophenyl acrylate) and its styrene copolymers were the most stable and the copolymers of styrene with 2,3-dibromopropyl acrylate had the best flame-retardant properties as was de...

Copolymers of Bromine-Containing Monomers. 6. Terpolymerization of Styrene, Acrylonitrile, and 2, 4, 6-Tribromophenyl Methacrylate

Abstract 2,4,6-Tribromophenyl methacrylate was terpolymerized with styrene and acrylonitrile in aqueous emulsion and dimethylformamide solution. Experimental terpolymerization data agreed well with values calculated from the Alfrey-Goldfinger equation. The relationship between monomer feed and terpolymer compositions is presented on a triangular coordinate graph. The lines of unique composition for each monomer and the lines of binary azeotropic composition for monomer pairs were established for both systems. No true azeotropic composition could be determined, but a “pseudo-azeotropic” region was established. The experimental terpolymerization data agreed well with the theoretical values over a wide range of monomer composition up to high conversions. The influence of 2,4,6-tribromophenyl methacrylate on the thermal stability and flammability behavior of the terpolymers is described.

Copolymers of Bromine-Containing Monomers. 5. Terpolymerization of Acryionitrile, Styrene, and Pentabromophenyl Acrylate

Abstract The terpolymerization of acryionitrile, styrene, and pentabromophenyl acrylate in dimethylformamide solution was investigated. Experimental terpolymerization data agreed well with calculations using the Alfrey-Goldfinger equation. The relationship between monomer feed and terpolymer compositions are presented on triangular coordinate graphs, and the lines of unique and the lines of binary azeotropic composition were identified. No point of true ternary azeotropic composition was found but a “pseudoazeotropic” region was identified. The experimental results of the terpolymerization agreed well with the theoretical curves over a wide range of monomer composition up to high conversions. The influence of pentabromophenyl acrylate units on the thermal and flammability characteristics of the terpolymers are described.