Microemulsion Copolymerizations of Methyl Methacrylate with Acrylonitrile and Styrene, and Characterization of Copolymers

678-688Microemulsion (M E) and conventional emulsion (CE) copolymerizations of the monomer pairs, methyl methacrylate (MMA)/ acrylonitrile (AN) and methyl methacrylate (MMA)/ styrene (STY), are carried out at 70oC with five different compositions of these monomer pairs in the initial reaction mixtures. Sodium lauryl sulphate (SLS), n-hexanol (HA) and potassium persulphate (KPS) are employed as surfactant, cosurfactant and free radical initiator, respectively. FTIR,1HNMR, TG/DTA ,GC, and GPC techniques are employed to characterize these copolymers. Kelen-Tudos (K-L) method is employed to evaluate the reactivity ratios for M E and C E copolymerizations of the monomer pairs, MMA/AN and MMA/STY, in the present study. The K-T method yields the reactivity ratios, rMMA and rAN, for ME copolymerization of MMA/AN as 2.50 ± 0.02 and 0.30 ± 0.02, respectively, and rMMA and rAN for the C E  copolymerization of MMA/AN are obtained as 1.60 ± 0.02 and 0.30 ± 0.02, respectively. The rMMA and rSTY for the M.E. copolymerization of MMA/STY are obtained from K-T method as 0.45 ± 0.02 and 0.65 ± 0.02, respectively, and the rMMA and rSTY for the C E copolymerization of MMA/STY are obtained as 0.74 ± 0.02 and 0.79 ± 0.02, respectively. The results obtained are compared with the literature