Polymerization of acrylonitrile initiated by Ce(IV)‐sucrose redox system: A kinetic study

Abstract

The polymerization of acrylonitrile (M), initiated by the free radicals formed in situ in the Ce (IV)-sucrose redox system, was studied in aqueous sulfuric acid medium under nitrogen atmosphere in the temperature range of 30-608C. . The rate of Ceric ion disappearance and the rate of polymerization R p have been measured. The effects of some water-miscible organic solvents, surfactants, ionic strength, and complexing agents on the rate of polymerization were investigated. The temperature-dependence of the rate was studied and the activation parameters were computed using the Arrhenius and Eyring plots. A mechanism consistent with the experimental data, involving Ce(IV)-sucrose complex formation, which generates free radicals, is suggested. The chain termination step of the polymerization reaction was determined.

Effect of pH Value on the aqueous precipitation copolymerization of acrylonitrile and vinyl acetate

“…The redox pair used in industries includes persulfate‐bisulphite, chlorate‐bisulphite, hydroxylamine sulfonate‐bisulphite, etc. The application of new redox pairs in aqueous polymerization process, such as K 2 CrO 4 ‐NaAsO 2 ,4, 18 potassium persulfate (K 2 S 2 O 8 )‐thiourea,19 Ce(IV)‐sucrose,20 chloramine‐T/hydrogen,21 Ce(IV)‐oxalic acid,22 were also investigated. The reductants are usually weak acid salts, which generate effective ingredient by ionization in aqueous solution at certain pH value.…”