SYNTHESIS OF TERPOLYMER METHYL METHACYLATE-STYRENE-BIS(4-METHACRYLOYLMETHYLPHENYL)-SULPHIDE

Abstract

Bis(4-methacryloylmethylphenyl)-sulphide (BMMPhS) was used as a third monomer to obtain terpolymers containing also methyl methacrylate (MM) and styrene (St). Copolymerization was carried out using two curing systems, the first consisting of benzoyl peroxide (BP) and NN-dimethylaniline (DMA) and the second one consisting of luperox (L), dimethylaniline and cobalt naphthenate (Co). Curing systems were examined as follows: 40% solution of BMMPhS in the mixed solvent MM-St (50:50) was polymerized and gelation times were measured at room temperature. Concentration of one component of the curing system was changed but the others were kept at the constant level. The influence of BMMPhS concentration on gelation times was also determined. The curing systems I BP(6%) + DMA(6%) and II L(4%) > ;DMA(8%) + Co(2%) were used to determine this influence of BMMPhS concentration on gelation times. Using the two above–mentioned curing systems, polymerizations of the compositions containing 40% of BMMPhS and 60% of mixed solvent were made. Quantity of MM and styrene in the solvent was changed in the range from 10% to 90% by weight of each component. Based on the obtained results two curing systems were chosen and used for preparation of terpolymer films. The curing systems were the same as in the case of determining the influence of BMMPhS concentration on gelation times. Content of BMMPhS in the films was 40% compared to the solvent but the content of MM and styrene in solvent changed as follows: 90%MM-10%St, 75%MM-25%St, 50%MM-50%St, 25%MM-75%St and 10%MM-90% St., when curing system I was used, and 75%MM-25%St, 60%MM-40%St and 50%MM-50%St. in the case of curing system II. Films of terpolymers were heated at 80°C for 4 h and next cut into stripes which were tested for mechanical properties like tensile strength, elongation at break, Young's modulus, hardness by Brinnell's method. Their thermal properties were also determined.