Influence of Polar Modifiers on the Anionic Solution 1,3-Butadiene Polymerization

The present work addresses the critical technological challenge of producing butadiene-based synthetic rubbers with the required skid resistance through anionic polymerizations at positive temperatures. Here, the effects of adding different polar modifiers (bis[2-(N,N-dimethylamino)ethyl] ether, BDMAE; ditetrahydrofurylpropane, DTHFP; tetramethylethylenediamine, TMEDA; sodium stearate, SS; sodium palmitate, SP; sodium tert-amilate, ST) into the monomer feed in anionic solution polymerizations of 1,3-butadiene are investigated. Different feed concentrations and combinations of polar modifiers were tested in order to achieve high yields and vinyl contents with initial temperature of 40 °C. The reactions were evaluated according to the obtained temperature and pressure profiles and physico-chemical characterizations of the obtained polymer, with help of statistical analyses. The results clearly showed the positive effects of using polar modifiers in the feed. Particularly, the combination of BDMAE and sodium salts provided products with high vinyl contents (> 50 %mol) with high yields (> 80 wt%), leading to high temperature peaks (> 90 °C), as desired to enhance the skid resistance. Moreover, the performed statistical analyses and proposed mathematical modeling revealed the existence of multivariate and complex correlations among the analyzed process variables. The findings from this investigation can be pivotal for advancing industrial applications in the production of skid-resistant synthetic rubber.