| Abstract: | A detailed study of the vulcanization of polybutadiene with various combinations of sulphur, tetramethylthiuram disuphide, ZnO, stearic acid, and zinc dimethyldithiocarbamate is reported. Vulcanization was conducted by heating samples at 2.5°C/min in a differential scanning calorimeter. The reaction was stopped at various points along the vulcanization exotherm, the soluble reaction products and residual curatives were extracted and analyzed, and the crosslink density and percentage polysulphidic crosslinks were determined. The overall reaction mechanism was found to be similar to that for polyisoprene, but the reaction, once initiated, was faster than in polyisoprene, the crosslink density was higher, and the percentage polysulphidic crosslinks was lower. These differences are discussed. © 1993 John Wiley & Sons, Inc. |
