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本文以叔丁氧基钾-正丁基锂作引发剂,甲苯作溶剂及链转移剂,研究了丁二烯阴离子链转移反应若干影响因素。含不同反离子引发剂的聚合体系中,向甲苯的链转移常数C_(?)分别为:C_(?)(Li)=0.11×10~(-3),C_(?)(Na)=0.40×10~(-3),C_s(K)=1.43×10~(3-)(K/Li=1.1),C_(?)(K)=1.26×10~(-3)(K/Li=0.5)。温度每升高10℃,增长速率常数增加1.7倍左右,而转移速率常数则增大2.1倍,表观转移活化能为62.8kJ/mol。随着K/Li的增大,链转移常数相应增大,当K/Li从0增加到0.5时,C_(?)增大约10倍,当K/Li从0.5增加到1.1时,C_s的变化很小。体系中可能存在向单体的链转移反应。
In this paper, potassium tert-butoxide-n-butyllithium as initiator, toluene as solvent and chain transfer agent, butadiene anion chain transfer reaction of several influencing factors. In the polymerization system containing different counterion initiator, the chain transfer constants C_ (?) To toluene are: C_ (?) (Li) = 0.11 × 10 -3, C_ (Na) = 0.40 (K / Li = 1.1), C _ (?) (K) = 1.26 × 10 ~ (-3) (K / Li = 0.5). For every 10 ℃ increase in temperature, the growth rate constant increased by 1.7 times, while the transfer rate constant increased by 2.1 times and the apparent activation energy for activation was 62.8 kJ / mol. As K / Li increases, the chain transfer constant increases correspondingly. When K / Li increases from 0 to 0.5, C_ (?) Increases about 10 times. When K / Li increases from 0.5 to 1.1, the change of C_s Very small. The system may exist in the monomer chain transfer reaction.