论文部分内容阅读
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.
A catalytic system composed of a metallocene compound (n-BuCp) 2TiCl2, a reducing agent (Sn) and an initiator phenyl glycidyl ether oxymethylene copolymer (Is) was used to initiate the living radical polymerization of styrene to synthesize a comb- The effects of polymerization temperature, polymerization time and the ratio of initiator to monomer on the polymerization of styrene were investigated.When the polymerization temperature was in the range of 65 ~ 95 ℃, with the increase of polymerization temperature, the molecular weight And the monomer conversion rate increased at a certain temperature, there was a linear relationship between the molecular weight of the polymer and the monomer conversion rate, and the molecular weight distribution of the polymer was narrow (Mw / Mn = 1.6 ~ 1.9) .Using GPC, WAXD , 13C (1H) -NMR was used to characterize the structure and properties of the polymer (boiling butanone soluble fraction) .GPC results showed that (n-BuCp) 2TiCl2 / Sn / NMR and WAXD results showed that the polystyrene segments were random structure; 1H-NMR results showed that the molecular chain of the polymer contained hydroxyl groups, and based on the results, the number of arms of the polymer molecule was 4, The number of groups is equal, and these results demonstrate that the polymerization mechanism is ring-opened by epoxy groups Styrene radical polymerization radical initiators.