含Bixan残基的大分子引发剂引发自由基聚合制备嵌段共聚物  

Preparation of PMMA-b-PSt by initiation of macroinitiator-containing fragments coming from Bixan-initiated polymerization of methyl methacrylate

作　　者：高冬[1] 刘莲英[1] 杨万泰[1] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029

出　　处：《北京化工大学学报（自然科学版）》2009年第2期49-52,共4页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家自然科学基金(50433040);北京市教委高分子化学与物理学科建设项目(XK100100433/XK100100540)

摘　　要：以9,9’-bixanthydrol(Bixan)为引发剂,在四氢呋喃溶液中于80℃下引发甲基丙烯酸甲酯(MMA)聚合,制得了末端带有引发剂残片的聚合物PMMA-XTOH。1H-NMR分析证实了聚合物链中含有引发剂残片,紫外光谱分析说明聚合物链两端均含有引发剂残片,聚合过程中单体转化率随反应时间的延长而增加,聚合物PMMA-XTOH分子量也随之增加,分子量分布为1.5～2。进一步以PMMA-XTOH为大分子引发剂引发苯乙烯本体聚合,制得了PMMA-b-PS嵌段共聚物,随反应时间延长,共聚物的分子量迅速增长,分子量分布明显下降。The free radical polymerization of methyl methacrylate was performed in THF at 80 ℃, with 9, 9＇ bixanthydrol （Bixan） as an initiator, and a precursor polymer containing fragments arising from Bixan at its chain ends was produced. Analysis of ^1H-NMR and UV spectroscopy confirmed the presence of the fragments. In the polymerization process, the monomer conversion and the molecular weight of PMMA-XTOH both increased with reaction time. The molecular weight distribution was in the range 1.5 to 2. Using the precursor polymer as a macroinitiator, the bulk polymerization of styrene was subsequently carried out and a PMMA-PSt block copolymer was obtained. GPC measurements indicated an increase in number average molecular weight and narrowing of molecular weight distribution in comparison with the precursor polymer.

关 键 词：Bixan 自由基聚合 大分子引发剂 嵌段共聚物 

分 类 号：O631.5[理学—高分子化学]