Polymerization of methyl methacrylate under ultrasonic irradiation. Part II. Polymerization in toluene–dimethyl sulfoxide mixed solvent



Polymerization of methyl methacrylate with Grignard reagents in mixed solvent of toluene and dimethyl sulfoxide (DMSO) under ultrasonic irradiation was carried out, and the effects of ultrasonic irradiation in connection with the mixed solvent on the stereoregularity and the properties of the polymers obtained were studied. The yield of polymers decreases with increasing concentration of DMSO in the solvent, and both yield and intrinsic viscosity of the polymers produced than ultrasonic irradiation are lower than those of polymers produced without it. A marked change in the configurational structure, namely, decrease in isotactic structure, is observed at a DMSO: toluene volume ratio of 5:95 in the series without ultrasonic irradiation, while a higher concentration of DMSO 15% by volume is required to obtain similar results in the series with ultrasonic irradiation.