SODIUM-INITIATED COPOLYMERIZATION OF STYR ENE AND BUTADIENE IN HYDROCARBON MEDIUM

An analysis of the main factors determining the process kinetics and m olecular masses of polymer formed in a nonterminating copolymerization accompanied by chain transfer to solvent is reported. The copolymeriz ation of styrene (M1) with butadiene (M2), initiated by homogeneous or ganosodium initiators in hydrocarbon medium, was also investigated exp erimentally. The following reactivity ratios were found: r1 = 0.42, r2 = 0.3. A relative chain transfer constant to toluene for homopolymeri zation of styrene was also determined: k(t)/k(p) = 4 x 10(-5). The cal culated dependences for the initial rates of copolymerization and mole cular masses of copolymers on the initial monomer feed composition are in good agreement with those obtained experimentally.