Regularities of diene copolymerization by coordination catalytic systems and the mechanism of stereoregulation

Abstract
A study has been conducted of the relative reactivity of a series of dienes (butadiene, isoprene, 2,3‐dimethylbutadiene, cyclohexadiene‐1,3), as well as of butadiene and styrene, in copolymerization by various coordination catalyst systems based on transition metals: nickel, cobalt, titanium, chromium, molybdenum, and tungsten. The microstructure of homopolymers and copolymers of dienes has been investigated. Regularities have been established in the mutual influence of the comonomers on the microstructure of a polymer chain. Experimental data on the influence of the concentration of diene monomer, and electron‐donating and electron‐accepting compounds on the microstructure of polydiene chain have been used in discussing the alternative mechanisms of stereoregulation in diene polymerization by active centers of the π‐allyl type.