Controlled one-step synthesis of hyperbranched 1,4-cis + 1,2-polybutadiene by using novel catalytic dithio system

Abstract

Cobalt Diethyldithiocarbamate + Ethylaluminumsesquichloride used as a catalyst for the synthesis of hyperbranched, low solution viscosity, high molecular weight 1,4-cis-polybutadiene containing 20–40% of 1,2-vinyl bonds. The effect of solvent used, catalyst and monomer concentrations, Al:Co ratio, temperature, polymerization time on conversion of butadiene were studied as controlling parameters. Polymer microstructure, intrinsic viscosity, molecular mass distribution, branching index were measured in the butadiene polymerization. Polymerization process was carried out in one step by controlled radical-coordination mechanism. The productivity of the used catalyst is 20.0–50.0 kg Polymer/g Co∙h with the 86.0–99.0% yield of polybutadiene. The obtained hyperbranched polybutadiene samples have branching indexes 0.30–0.75. Synthesized hyperbranched 1,4-cis + 1,2-polybutadiene has been used in transdermal drug delivery system.

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