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以Ti(n-C_8H_17O)_4-Al(i-C_4H_9)_s为催化剂合成1,2-聚丁二烯,采用Ti-Bd-Al三组分陈化方式,考察了陈化温度和时间对聚合的影响。结果发现,Ti:Bd:Al=1:20:10,在90℃高温下陈化0.5h;或Ti:Bd:Al=1:20:15,75℃陈化1.5h,Ti的催化活性较催化剂组分单加或室温陈化提高50％以上,而Al的用量却降低了50—70％,所得聚丁二烯的分子量高,分子量分布较窄,凝胶含量也较低。动力学研究表明,高温陈化引起的催化活性提高,不是因为提高了催化剂的利用率,而是由于形成的活性种有较大的增长速率常数。
1,2-polybutadiene was synthesized by using Ti (n-C_8H_17O) _4-Al (i-C_4H_9) _s as catalyst. The effects of aging temperature and time on the polymerization Impact. The results showed that Ti: Bd: Al = 1:20:10, aging at 90 ℃ for 0.5h, Ti: Bd: Al = 1:20:15, aging at 75 ℃ for 1.5h, The addition of catalyst components alone or at room temperature increased by 50% or more, while the amount of Al was reduced by 50-70%. The resulting polybutadiene had a high molecular weight, a narrow molecular weight distribution and a low gel content. Kinetic studies have shown that the catalytic activity caused by aging at high temperatures is not due to increased catalyst utilization, but due to the larger growth rate constants of the active species formed.