Abstract: The mechanism of the anionic polymerization of butadiene and the quantitative relatioship of vinyl content versus the concentration of lewis bases including THF, DOX and Et2O were studied. Results obtained indicated that experimental data collected in the presence of the Lewis bases employed conformed with the quantitative relationship presented by the authors in their previous paper on this same subject. A complex equilibrium constant K and a coordination solvated index n were determined from the intercept and slope of the logarithmic equation at different temperatures. Moderate increases in reaction temperatures tended to bring about slight decreases in the values ot K and n. Quantitative relationships between K and/or n and temperature were obtained. A more generalized polymerization mechanism of butadiene was thereby proposed.