Butadiene polymerization in the presence of butyl lithium modified with sodium butylate

Abstract Dilatometry in toluene, cyclohexane and heptane as been used to study butadiene polymerization kinetics over n-butyl lithium in combination with sodium tert-butylate as initiators. The molecular characteristics, the elasto-plastic and physico-mechanical properties of the synthesized polymers were also examined. The type of the hydrocarbon solvent has been found to affect the process rate and the micro-structure of the polymers. The chain-transfer constant to toluence has been estimated at 0·4 × 10 −4 for a 0·5 concentration ratio of Na : Li at 60°C. The found characteristics of the process kinetics and the polymer properties are explained as due to the reactivity changes of the reactive centres which depend in the contentsof NaC bonds in them.