Chap.6 配位聚合 Coordination Polymerization 6.1 引言 6.2 聚合物的立体异构现象 6.3 烯烃的 Ziegler-Natta 聚合 6.4 共轭二烯的立体定向聚合 6.5 配位聚合的工业应用 6.1 引言 Introduction 1938 英国 I.C.I 公司，低密度聚乙烯 (0.91~0.93), 又称高压聚乙烯 1953 德国 K. Ziegler, TiCl4-AlEt3, 高密 度聚乙烯 (0.94~0.96) 1954 意大利 G.Natta, TiCl3-AlEt3 等规聚 丙烯 (mp 175℃) Goodrch-Gulf Co. TiCl4-AlEt3, 高顺式聚 异戊二烯（天然橡胶） 1963 Ziegler 和 Natta 共获 Nobel 奖 The Ziegler-Natta initiators (also referred to as catalyst) are a remarkable group of initiators. They are only initiators that polymerize -olefins such as propene and 1-butene, which are not polymerized by either radical or ionic initiators. Ziegler-Natta initiators are important not only for obtaining stereoregular polymers but also for the polymerization of ethylene. Polyethylene obtained by these initiators is different in structure and properties from that obtained by radical polymerization. 6.2 聚合物的立体异构现象Stereoisomerism in Polymers 6.2.1 立体异构类型Types of Stereoisomerism in Polymer Stereoisomerism构造 constitution 构型 configuration构象 conformation结构 structure对映异构体 enantiomers Constitutional isomerism is encountered whenpolymers have the same overall chemical compositionbut atom or groups of atoms are connected in different order.CH-OCH3nCH2CH2-OnCH2-CHOHnPolyacetaldehyde Poly(ethylene oxide) Poly(vinyl alcohol)CH3CHOCH2 CH2OCH2-CHOCOCH3nhydrolysisCH2=CHOCOCH3constitutional isomers CH2-CCH3COOCH3CH2-CHCOOC2H5nnPoly(methyl methacrylate) Poly(ethyl acrylate)CO(CH2)5NHNH(CH2)6NHCO(CH2)4COnnPoly( -caprolactam) Poly(hehamethylene adipamide)HO2C(CH2)4CO2H + NH2(CH2)6NH2NHO Isomeric polymers can also be obtained from a single monomer.CH2=CXYCH2 CXYCH2 CXYCH2 CXYCH2 CXYCH2 CXYC...
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