4[1].3 络合离子.pptVIP

4.4 Coordination Complex Polymerization 4.4 Coordination Complex Polymerization 4.4.1 Steric regularity of polymerization 4.4.2 Ziegler-Natta polymerization of nonpolar alkene monomer 4.4.3 Coordination polymerization of dialkene monomer 4.4.4 Polymerization of π-allyl complex compound and chromic oxide catalyst 4.4.1 Stereoregularity of Polymer (1) Isomers of Polymer What is isomerism? The atoms or atomic groups in a polymer molecule have different interconnection orders, which bring out isomerism or structural isomerism. Fox example：Polymerizing same or different monomers can produce polymers of same chemistry constitute and different structures. (1) Isomers of Polymer For example , polymer with structure unit －[ C2H4O－] n can be polyvinyl alcohol or polyethylene oxide Fox example , PMMA and polyethyl acrylate , and polyamide , like nylon－6 and nylon一66 ,are all isomers with different properties. (1) Isomers of Polymer With different interconnection forms among structure units , sequence isomerism occurs. For example , isomerism phenomenon of head-end connection and head-head connection . Polymers of head-end , head-head and random interconnection have the same chemistry composition , while their properties differ. （2）Solid Isomers of Polymer Solid Isomerism： Solid isomers of polymer indicate the kind of polymers , which have the same chemistry constitute and connection structure , and differs just in conformation , that is to say , the steric arrangements of them are different. Solid isomerism can be classified into two categories： One is caused by the chiral center, calls optical isomer. R (Right) form S (Left) form The other kind is caused by the double bond , called geometry isomer. Z（cis conformation） E（trans conformation） （2）Solid Isomers of Polymer How to distinguish configuration and conformation Conformation-----indicates the steric iso