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由钴催化体系合成的间规1,2-聚丁二烯是结晶性的,熔点205—210℃,与1,2-链节含量无关。低1,2-含量(12—20mol％)时,热氧化峰温为185℃左右,高1,2-含量(95—100mol％)时,200到240℃。换言之,与主链双键相比,侧链乙烯基的热氧化反应发生在更高的温度,即在熔融后的较窄的温度范围表现出较大的热效应。高1,2-含量间规聚丁二烯热氧化的热效应和活化能值,似与合成转化率有一定联系,当达到一定转化率时,热效应急剧增高,而活化能降低,估计这与残留在试样中催化剂的量及存在形式有关。
Syndiotactic 1,2-polybutadiene synthesized by a cobalt catalyst system is crystalline with a melting point of 205-210 ° C, independent of the content of 1,2-mer. Low 1,2-content (12-20 mol%) gives a peak temperature of about 185 ° C for thermal oxidation and 200 to 240 ° C for high 1,2-content (95-100 mol%). In other words, the thermal oxidation reaction of the side chain vinyl occurs at a higher temperature than the main chain double bond, ie, shows a larger thermal effect in a narrower temperature range after melting. The thermal effect and activation energy value of the syngas-polybutadiene with high content of 1,2-content seems to be related to the conversion rate of synthesis. When a certain conversion rate is reached, the thermal effect increases sharply and the activation energy decreases. The amount of catalyst in the sample and the existence of the form.