锂系阴离子聚合机理及形成的插花状聚合物超分子  

Anionic Polymerization Mechanism Initiated by Organolithium and the Ikebana Supramolecules Polymerized Through It

作　　者：吴尚翰[1] 管涌[1] 陈波[1] 危大福[1] 李书召[1] 郑安呐[1] 

机构地区：[1]华东理工大学材料科学与工程学院上海先进聚合物材料重点实验室超细材料制备与应用教育部重点实验室,上海200237

出　　处：《高分子材料科学与工程》2014年第2期57-61,共5页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(5093302);国家863项目(2012AA040306):上海市重点学科建设项目(B502);超细材料制备与应用教育部重点实验室项目(08DZ2230500)

摘　　要：采用n-BuLi与t-BuLi分别引发苯乙烯、α-甲基苯乙烯以及甲基丙烯酸甲酯的本体及溶液的阴离子聚合。用凝胶渗透色谱及核磁共振锂谱对聚合过程进行了研究。发现以n-BuLi引发聚合初期,可形成一种插花状聚合物超分子,并违反经典的真溶液理论。其在室温时在自身的良溶剂中保持不溶,除非在接近该聚合物Tg温度长时间搅拌,方可令其解离。t-BuLi在引发聚合时,同时存在四缔合体及二缔合体活性种。随着聚合的延续,四缔合体逐渐解离成二缔合体活性种。在非极性条件下,t-BuLi可形成少量无活性的超大缔合物,四氢呋喃可令其解离。The bulk and solution polymerization of styrene, α-methyl styrene and methyl methacrylate were initiated by n-butyllithium （n-BuLi） and t-butyllithium （t-BuLi） and characterized by GPC and 7Li-NMR spectra. It was found that at the beginning of the polymerization initiated by n-BuLi, a kind of ikebana supramolecule of homopolymer could be formed, which conflicted with the classical mechanism of true solution, i.e., it could not dissolve in its good solvent at room temperature. The supramolecule would dissociate when the temperature was close to Tg of the polymer under mixing for a long time. There existed simultaneously two kinds of active species, tetramer and dimer aggregates, once the polymerization was initiated by t-BuLi. As the polymerization carried on, the tetramer aggregate was disassembled gradually into the dimer aggregate. Under the nonpolar condition, t-BuLi could form some of overlarge and inactive aggregates, which could be disassembled by the addition of THF.

关 键 词：有机锂 阴离子聚合 机理 插花状 超分子 

分 类 号：TQ316.324[化学工程—高聚物工业]