期刊文献+

苯乙烯的低温原子转移自由基聚合:扩散效应导致的加速现象 被引量:1

Low-Temperature Atom Transfer Radical Polymerization of Styrene:Diffusion-induced Acceleration
原文传递
导出
摘要 研究了以苯乙烯(St)和N-[4-(2-溴丙酰氧基)苯基]马来酰亚胺(BPPM)的交替共聚物P(St-alt-BPPM)为大分子多官能度引发剂,以CuBr/2,2'-联吡啶(bpy)为催化体系,环己酮为溶剂,在60或80℃下进行St的原子转移自由基聚合(ATRP).结果表明,反应呈现活性聚合的假一级反应动力学特征,聚合物分子量随着单体转化率上升而增加,降低反应温度将减低反应速率,但是所得聚合物[P(St-alt-BPPM)-g-PS]分子量分布更窄.水解实验证明该过程具有一定可控性.由于类似的单官能度引发剂无法在同等条件下顺利引发St的ATRP,因此采用大分子多官能度引发剂可以大幅度降低ATRP的反应温度.此加速现象被归因于CuBr/bpy从大分子引发剂线团外向线团内扩散,而CuBr2/bpy则从大分子引发剂线团内向线团外扩散,从而提高大分子引发剂线团中的自由基浓度和聚合反应速率. The CuBr/2,2'-bipyridine (bpy)-catalyzed atom transfer radical polymerization (ATRP) of styrene (St) initiated by well-defined poly(styrene-alt-N-[4-(a-bromopropyloxy)phenyl]maleimide) [P(St-alt-BPPM)] in cyclohexanone at 60 and 80℃ was investigated. The results showed that the reaction appeared to follow pseudo-first order kinetics, and the molecular weight (Mw) of the polymer P(St-alt-BPPM)-g-PS increased with the monomer conversion. A lower reaction temperature would reduce the reaction rate and lead to a narrower molecular weight distribution of the P(St-alt-BPPM)-g-PS. The Mw data of the PS side chains confirmed that the process was in a controlled fashion. The ATRP of St cannot be successfully initiated by low-Mw analogue under similar conditions, so using multi-functional macroinitiator would significantly reduce the reaction temperature. Such an acceleration effect was attributed to the diffusion of CuBr/bpy from the macro-initiator coil outside to inside and that of CuBr2/bpy from inside to outside, resulting in an enhanced concentration of propagating radicals inside the coil and an faster polymerization rate.
出处 《化学学报》 SCIE CAS CSCD 北大核心 2011年第7期853-862,共10页 Acta Chimica Sinica
基金 国家自然科学基金(No.20674033) 江苏省自然科学基金(No.BK2008142)资助项目
关键词 苯乙烯 原子转移自由基聚合 大分子多官能度引发剂 扩散效应 加速 styrene atom transfer radical polymerization (ATRP) multi-functional macroinitiator diffusion effect acceleration
  • 相关文献

参考文献4

二级参考文献20

  • 1ShiYan(石艳).Synthesis of Branched Polymers by Controlled Radical Polymerization(活性自由基聚合法支化聚合物合成研究).Doctoral Dissertation of Beijing University of Chemical Technology(北京化工大学博士学位论文),2005.
  • 2Shi Y, Fu Z F, Yang W T. J Polym Sci, Part A : Polym Chem,2006,44:2069 - 2075.
  • 3Deng G Q, Chen Y M. Macromolecules,2004,37 : 18 - 26.
  • 4Ren Q,Jiang B B,Zhang D L,Yu Q,Fang J B,Yang Y,Chen J H. Europ Polym J,2005,41:2742 -2752.
  • 5Ren Q, Gong F H, Jiang B B,Zhang D L Fang J B, Guo F D. Polymer,2006,47:3382 -3389.
  • 6Cao Y, Hong Y, Zhai G Q, Zhang D L, Song Y,Yu Q, Ren Q, Jiang B B. Polym Int,2008,57 : 1090 - 1100.
  • 7Gamier S. Novel Amphiphilic Diblock Copolymers by RAFT-Polymerization, Their Self-organization and Surfactant Properties. Doctoral Dissertation of Potsdam University,2005.
  • 8Coote M L. M acromolecules, 2004,37 : 5023 - 5031.
  • 9Coote M L,Radom L. J Am Chem Soc,2003,125:1490- 1491.
  • 10Weimer M W, Frechet J M J, Gitsov I. J Polym Sci Part A:Polym Chem, 1998,36:955 -970.

共引文献19

同被引文献3

  • 1Ding L M. Comb polymer electrolyte[J]. Polym. Bull., 1996, 37 (5) : 639-646.
  • 2Cao Y, Hong Y, Zhai G. Q, et al. Facile synthesis and characterization of star-shaped polystyrene: self-condensing atom transfer radical eopolymerization of N-[ 4-(a-bromoisobutyryloxy) phenyl]maleimide and styrene [J]. Polym. Int., 2008, 57(10) : 1090-1100.
  • 3方艳,曹赟,张爱萍,翟光群,孔立智,张东亮.苯乙烯与N-取代马来酰亚胺的可逆加成-断裂链转移交替共聚合[J].高分子学报,2010,20(1):51-58. 被引量:3

引证文献1

二级引证文献1

相关作者

内容加载中请稍等...

相关机构

内容加载中请稍等...

相关主题

内容加载中请稍等...

浏览历史

内容加载中请稍等...
;
使用帮助 返回顶部