Propene, copolymerization Ziegler-Natta polymerization

Most unsaturated substances such as alkenes, alkynes, aldehydes, acrylonitrile, epoxides, isocyanates, etc., can be converted into polymeric materials of some sort—either very high polymers, or low-molecular-weight polymers, or oligomers such as linear or cyclic dimers, trimers, etc. In addition, copolymerization of several components, e.g., styrene-butadiene-dicyclo-pentadiene, is very important in the synthesis of rubbers. Not all such polymerizations, of course, require transition-metal catalysts and we consider here only a few examples that do. The most important is Ziegler-Natta polymerization of ethylene and propene. 

Several Ziegler-Natta catalyst systems have been repotted to (co)polymerize carboxylic acid containing monomers, for example, in the copolymerization of aluminum-protected 10-undecenoic add with propene " or 1-hexene and 4-methyl-l-pentene ° with a-olefins using TiCl3/Et2AlCl as catalyst system. 

Cyclopentene can be copolymerized with ethene or propene by heterogeneous and homogeneous Ziegler-Natta catalysts. Crystalline or elastomeric copolymers are obtained depending on the cyclopentene content and the part of ring-opening or vinyl-type polymerization mechanism. Metallocene/MAO catalysts are very active in the copolymerization of cyclopentene with ethene. In contrast to the homopolymerization of cyclopentene, the cyclic olefin is incorporated into the copolymer chain by 1,2-enchainment. 

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