原子转移自由基聚合合成支化聚丙烯腈

Synthesis of branched polyacrylonitrile by atom transfer radical polymerization

以二乙烯苯为支化单体,α-溴代异丁酸叔丁酯为引发剂,CuBr和2,2′-联吡啶为催化体系,利用本体和溶液原子转移自由基聚合合成了支化聚丙烯腈。采用核磁共振谱仪、凝胶渗透色谱仪和多角度激光光散射仪等测试了聚合物结构、相对分子质量及其分布。用无水乙酸钠对支化聚丙烯腈进行末端改性,得到了在硫氰酸钠水溶液中性能稳定、可长期保存的支化聚丙烯腈,而改性对聚合物的耐热性能没有影响。

The authors synthesized branched polyacrylonitrile via atom transfer radical bulk and solution polymerization, using divinylbenzene as branching monomer, tert-butyl-2-bromoisobutyrate （t-BBiB） as initiator and CuBr and 2, 2＇-bipyridine as catalyst system. The structure and relative molecular weight and its distribution of the resultant polymer were analyzed by gel permeation chromatography （GPC）, multi-angle laser light scattering spectrometry （MALLS） and nuclear magnetic resonance spectroscopy （NMR）. The branched polyacrylonitrile underwent end group modification by anhydrous sodium acetate; the modified polymer could be stored stably in sodium thiocyanate solution for long period. The modification brought about no impact on thermal stability of the branched polyacrylonitrile.