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Abstract:
A new catalyst system based on easily accessible cross-linked (by Diels-Alder reaction) polymeric supports, functionalized with nucleophilic polyethyleneoxide-monomethylether (PEO-M) is presented. The metallocene-MAO complex is noncovalently bonded to the support, avoiding a complicated polymer analogous metallocene synthesis. The polymerisation of propene and ethene with Me2Si(2MeBenzlnd)(2)ZrCl2 as metallocene is performed using this support. The resulting polymers have high molecular weights and melting points and narrow molecular weight distribution. Polypropene is produced with 95% isotacticity similar to that from homogeneous catalysis. The productivities of up to 8600 for polypropene and 1300 for polyethene ( kg polymer / mol Zr h bar) are comparably high. The product beads exhibit a good morphology, which can be explained by fragmentation processes of the support due to the reversibility of the network formation.
