中华医学超声杂志

应用化学 ›› 1988, Vol. 0 ›› Issue (2): 23-28.

• 研究论文 • 上一篇    下一篇

丁二烯/甲苯/叔丁氧基钾-正丁基锂体系聚合反应的研究 Ⅲ.链转移

周广滨1, 许国津2, 李晶洁2   

  1. 1. 华南工学院;
    2. 大连工学院化工学院高分子材料系
  • 收稿日期:1986-10-06 修回日期:1987-09-28 出版日期:1988-04-10 发布日期:1988-04-10
  • 基金资助:
    中国科学院基金委员会资助

A STUDY OF THE BUTADIENE/TOLUENE/POTASSIUM BUTOXIDE-N-BUTYLLITHIUM POLYMERIZATION SYSTEM Ⅲ.CHAIN TRANSFER

Zhou Guangbin1, Xu Guojin2, Li Jingjie2   

  1. 1. South China Institute of Technology;
    2. Dalian Institute of Technology, Polymer Division
  • Received:1986-10-06 Revised:1987-09-28 Published:1988-04-10 Online:1988-04-10

PDF

408

被引次数

7

摘要： 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Ci分别为:Ci(Li)=0.11×10-3,Ci(Na)=0.40×10-3,Cs(K)=1.43×103-(K/Li=1.1),Ci(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,Ci增大约10倍,当K/Li从0.5增加到1.1时,Cs的变化很小.体系中可能存在向单体的链转移反应.

关键词: 丁二烯, 阴离子引发聚合反应, 甲苯, 链转移

Abstract: The chain transfer of butadiene polymerization was studied with n-butyl lithium and potassium butoxide as catalyst, toluene as solvent and chain transfer agent. The chain transfer constants to toluene with different counterions were found to be:Cs(Li)=0.11x10-3, Cs(Na)=0.40x10-3, Cs(K)=1.43x10-3, (K/Li=1.1), Cs(K))=1.26x10-3K/Li=0.5) respectively. The propagation rate constant increased 1.7 times for every 10℃ increase in temperature, and the chain transfer rate constant increased 2.1 times. The apparent activation energy of chain transfer was 62.8 kJ/mol. When increeasing K/Li from 0 to 0.5, Cs increased about 10 times, but when K/Li increased from 0.5 to 1.1, Cs changed scantly. Probably there existed certain chain transfer to monomer in this system.

Key words: Butadiene Anionic initiation polymerization Toluene Chain transfer

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