高等学校化学学报 ›› 2006, Vol. 27 ›› Issue (1): 192-195.

• 研究论文 • 上一篇    下一篇

HTEMPO和TMPD调控下MMA可控/活性光聚合研究

刘晓暄, 任亚娥, 张婷, 韩梅, 吴光国   

  1. 汕头大学理学院化学系先进材料研究所, 汕头 515063
  • 收稿日期:2004-12-16 出版日期:2006-01-10 发布日期:2006-01-10
  • 通讯作者: 刘晓暄(1957年出生), 男, 博士, 教授, 主要从事高分子光化学及反应动力学研究. E-mail: xxliu@stu.edu.cn
  • 基金资助:

    国家自然科学基金(批准号: 20474036)、 教育部科学技术重大研究项目(批准号: 02114)和广东省自然科学基金(批准号: 021241)资助.

Controlled/Living Photopolymerization of Methyl Methacrylate Mediated by Bimolecular Systems for HTEMPO/2,2,6,6-Tetramethyl-Piperidinone

 LIU Xiao-Xuan, REN Ya-E, ZHANG Ting, HAN Mei, WU Guang-Guo   

  1. Department of Chemistry and Institute of Advanced Materials, College of Sciences, Shantou University, Shantou 515063, China
  • Received:2004-12-16 Online:2006-01-10 Published:2006-01-10
  • Contact: LIU Xiao-Xuan,xxliu@stu.edu.cn

摘要:

以HTEMPO(2,2,6,6-四甲基-4-羟基哌啶-1-氧自由基)和TMPD(2,2,6,6-四甲基哌啶酮)为调控介质, 以Irgacure 651为引发剂, 研究了甲基丙烯酸甲酯(MMA)光聚合体系的控制反应动力学, 比较了单分子(HTEMPO为调控介质)和双分子(HTEMPO和TMPD为调控介质)调控体系, 并讨论了HTEMPO和HTEMPO/TMPD在MMA光聚合体系中的调控作用、 光敏化作用和原位光氧化反应. 结果表明, 对MMA光聚合体系, 以HTEMPO/TMPD为控制介质的双分子调控体系是有效的, 获得了良好的ln(\[M0\]/\[M\])与时间, 数均分子量与转化率之间的线性动力学关系, 并且PMMA均聚物的多分散性指数(PDI)随着转化率的提高而减小. 在高转化率(>85%)下, 体系的多分散性指数(PDI)最小值可达到1.2.

关键词: 可控/活性光聚合; 甲基丙烯酸甲酯; 氮氧自由基; 2,2,6,6-四甲基-4-羟基哌啶-1-氧自由基; 2,2,6,6-四甲基哌啶酮

Abstract:

Controlled/living photopolymerization of methyl methacrylate(MMA) mediated by bimolecular systems for 4-hydroxy-2,2,6,6-tetramethyl-piperidinyl-1-oxyl(HTEMPO) and 2,2,6,6-tetramethyl-piperidinone(TMPD) was performed at ambient temperature. The effects of HTEMPO, TMPD and their different molar ratio as a mediator and photo-induced oxidization in situ of TMPD in the system were discussed respectively. It is shown that the molecular weight(Mn) of MMA homopolymer increased linearly and the polydispersity index(PDI) decreases with the conversion increasing, even until the conversion up to 80%, mediated by bimolecular system with both HTEMPO and TMPD, which is the characteristic of a controlled/living free radical polymerization. It is found that the obtained MMA homopolymer prepared by the photopolymerization exhibited a narrow molecular weight distribution as was characterized by GPC, the smallest value of PDI is 1.2. The result also shows that the bimolecular systems with HTEMPO/TMPD as a mediator has a  better controlling kinetic performance than that only mediated by HTEMPO under the same condition.

Key words: Controlled/living photopolymerization; Methyl methacrylate; Nitroxide; HTEMPO;

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