(n-BuCp)_2TiCl_2/Sn/I_s引发合成梳形羟基功能化无规聚苯乙烯及聚合物结构与性能的研究  

SYNTHESIS AND CHARACTERIZATION OF COMB-LIKE HYDROXYL FUNCTIONALIZED ATACTIC POLYSTYRENE INITIATED BY (n-BuCp)_2TiCl_2 /Sn /I_s CATALYTIC SYSTEM

作　　者：汪红丽[1] 孔媛[1] 马利福[1] 盛亚平[1] 黄启谷[1] 杨万泰[1] 

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室材料科学与工程学院,北京100029

出　　处：《高分子学报》2010年第4期423-428,共6页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号20574003);北京市教委重点学科共建项目(项目号XK100100540;XK100100640);"长江学者和创新团队发展计划"教育部创新团队"高性能有机高分子材料集成制备"(编号IRT0706)资助项目

摘　　要：采用茂金属化合物(n-BuCp)2TiCl2,还原剂(Sn),引发剂苯基缩水甘油基醚甲醛共聚物(Is)组成的催化体系引发苯乙烯活性自由基聚合,合成梳形羟基功能化无规聚苯乙烯.考察了聚合温度、聚合时间及引发剂与单体的比例对苯乙烯聚合的影响.当聚合温度在65～95℃范围内,随着聚合温度的升高,聚合物的分子量及单体转化率增加;在一定温度下,聚合物的分子量与单体转化率之间存在线性增长关系,且聚合物的分子量分布较窄(Mw/Mn=1.6～1.9).采用GPC,WAXD,13C(1H)-NMR对聚合物(沸丁酮可溶级分)的结构与性能进行了表征.GPC结果证明(n-BuCp)2TiCl2/Sn/Is引发苯乙烯聚合为活性聚合;13C-NMR和WAXD结果说明聚苯乙烯链段为无规结构;1H-NMR结果表明聚合物分子链中含有羟基,并根据其结果计算出聚合物分子的臂数为4,与引发剂Is的环氧基团数相等.这些结果证明了其聚合机理是经环氧基团开环后形成的自由基引发苯乙烯自由基聚合.Comb-like hydroxyl functionalized atactic polystyrene was synthesized using the catalytic system （ n-BuCp ）2TiCl2 /Sn/Is via living radical polymerization with Sn as the reducing agent and poly- [（phenylglycidyl ether）-co-formaldehyde]（Is） as the initiator. The effect of polymerization conditions,such as temperature,time,as well as the ratio of initiator to monomer on the polymerization performance was investigated. The catalytic active center was stable at the temperature range of 65 ～ 95℃ ,and the propagation rate increased with temperature. The structure and the properties of the obtained polymer were characterized by GPC,13 C-NMR,WAXD and1H-NMR. The GPC result indicated that a linear dependence of Mn on the monomer conversion was observed in each case,and the resulting polymer exhibited a rather low polydispersity （Mw /Mn = 1. 6 ～ 1. 9） even the polymerization time （6,8,12,16,18 h） or the ratio of initiator to monomer （[Is]/ [St] = 1 /250,1 /500,1 /750 ） had been changed,which confirmed that living radical polymerization characters prevailed in the polymerization process. The results of 13 C-NMR and WAXD suggested that the polymer is featured by an atactic structure. The 1H-NMR results showed that the polymer molecules possessed hydroxyl groups,and the number of arms in each polymer molecule was in good agreement with the number of epoxy functional groups in the initiator （Is）,which indicated the radicals derived from ring opening reaction of epoxide were the active species for living radical polymerization of styrene.

关 键 词：茂金属化合物 活性自由基聚合 梳形 羟基功能化无规聚苯乙烯 

分 类 号：O632.13[理学—高分子化学]