Aqueous polymerization of acrylamide initiated by acidic thiourea/potassium bromate redox system

Abstract

Abstract The aqueous polymerization of acrylamide initiated by bromate/thiourea redox system has been studied in acidic media at 25 ± 0.2°C in a nitrogen atmosphere. The rate of polymerization has been found to vary with the first power of the potassium bromate concentration within the range 0.75·10 −2 to 2.0·10 −2 mole·1 −1 and nearly with the first power of the hydrochloric acid concentration within the range 2.85·10 −2 to 8.55·10 −2 mole·1 −1 . However, the rate of polymerization is independent of the thiourea concentration, but varies with the first power of the monomer concentration within the range 6.0·10 −2 to 10.0·10 −2 mole·1 −1 . The initial rate increases but the maximum conversion decreases as the temperature increases within the range 19 to 35°C. The over all energy of activation has been found to be 22.9 kcal·mole −1 within the temperature range mentioned above. Water miscible organic solvents and mono‐ and dibasic salts show the same effect as given by MISRA et al . The effect of cationic and anionic surfactants has been found to increase and decrease the rate of polymerization (R p ) respectively, however non‐ionic detergents have no effect on the (R p ).