Influence of organoaluminium compounds on the molecular weight characteristics of polybutadiene formed in the presence of sodium initiators

A study has been made of the MW and MWD of butadiene polymers prepared in the presence of complexes of diisobutyl aluminium hydride in toluene and in toluene mixtures with THF and with 4,4-dimethyl-1,3-dioxane. Aluminium introduced into the active centre sharply lowers the rate of chain transfer to toluene. In the presence of initiators containing diisobutyl aluminium hydride the chain transfer rate is significantly higher in the case of low Al/Na ratios.