| The dissertation involves the following works: the synthesis of non-bridged metallocene, supporting the metallocene by using silica(MS) and montmorillonite(MTT) as carriers, copolymerization of ethylene with 1-hexene by homogeneous and heterogeneous catalyst combined with methyl aluminoxane, polymerization of propylene by homogeneous catalyst combined with methyl aluminoxane, and characterization of the structure and its properties of the resultant polymer. And the correlation between metallocene structure and polymerization behavior and polymer properties is discussed. New methods to characterize the structural homogeneity of copolymer are developed.Two substituted indanones were synthesized through different procedures: 2,7-dimethylindanone and 2,5,7-trimethylindanone. After reduction and dehydration, substituted indenes, 2,4-dimethylindene and 2,4,6-trimethylindene, were obtained from the corresponding indanones.. The influence of different start substances on the composition and yield of the indanones was staudied. The isomers from double-bond position in 2,4,6-trimethylindene were separated by chemical approach, and the mechanism was discussed.Using the substituted indenes as the organic ligand, two non-bridged metallocenes were synthesized: (2,4-Me2lnd)2ZrCl2(cat24) and(2,4,6-Me3lnd)2ZrCl2(cat246). The adopted procedure gave high yield with cheap raw materials and less pollution.Using mesoporous silica gel(MS) and montmorillonite(MTT) as carriers, supported catalysts of cat24 and cat246 were prepared. Three heterogeneous catalysts,MS24, MS246, MTT24, were obtained. The Zr content in the supported catalyst was determined by UV spectroscopy.In the present study, copolymerization of ethylene with 1-hexene was carried out by using cat24, cat246, cat247, MS24, MS246 and MTT24 combined with MAO as cocatalyst, in which cat247 is (2,4,7-Me3Ind)2ZrCl2. A new activity-comonomer concentration relation was found in the copolymerization catalyzed by cat24 at 0癈. The polymerization activity underwent changes of decrease-increase-decrease with increase of hexene feed concentration. This phenomenon has not been reported in literatures. It is reasoned that the integration of various effects caused by the comonomer had made such changes. This explanation is proved by the polymerization behavior of cat24 at 50癈 and cat246 at 0癈 and 50癈. Through the comparison of activity at different homogenous catalyst concentration, the important influence of compact/loose ionpair of active site on activity was found. And according to this opinion, the copolymerization ability of catalyst is estimated. The estimation is identical with the observed result. Supporting of metallocene exerted important influence on the polymerization activity. The activity maintained a high level to ethylene homopolymerization and observably decreased to ethylene/1-hexene copolymerization for the silica supporting system. It indicates that the silica carrier has minor effect on the ethylene diffusion, but hinders the diffusion of 1-hexene. The activity of both homo- and co-polymerization decreased for montmorillonite suupporting system.The comonomer content incorporated in polymer was determined by using 13C-NMR and IR. The comonomer content is proportioned to the feeding concentration. The number and position of substituent on ligand of metallocene has strong effect on copolymerization ability. The difference in copolymerization ability of metallocenes were interpreted according to the different metallocene conformations and the change of ligand rotation energy barrier resulted from the number and position of substituent on ligand of metallocene. The number and position of substituents in ligand is the original reason. The "two sites alternating mechanism"(TSAM) of non-bridged metallocene is developed.Thermal property of the ethylene/1-hexene copolymer was characterized by using stepwise isothermal segregation fractionation DSC. The lamella thickness is calculated. The short-chain branching (SCB) d...
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