Recent Progresses in Catalytic Insertion Polymerization of Olefins

Recent Progresses in Catalytic Insertion Polymerization of Olefins 

Since the aforementioned investigations, significant advances in aqueous catalytic insertion polymerization have only been made over the past decade. Alternating copolymerization of olefins with carbon monoxide, polymerization of ethylene and 1-olefins, and polymerizations of norbomenes and of butadiene have been studied. 

Since the aforementioned pioneering discovery of Reppe and Magin, catalytic ole-fin-CO copolymerization (in non-aqueous media) has found continuous, widespread interest. Carbon monoxide is an exceptionally cheap starting material, and fhe aliphatic alternating polyketones obtained possess attractive materials properties [31-33]. 

A major breakthrough has been the finding that catalysts based on cationic palladium] 11) complexes with bidentate ligands, most often diphosphines, exhibit substantially increased activities in ethylene-carbon monoxide copolymerization by comparison to previously known nickel(ll) and palladium(II) systems [34—38]. Methanol is typically used as a reaction medium, demonstrating the stability of fhese catalysts towards protic media. 

An alternating ethylene-CO copolymer melts at 257 C. Incorporation of propylene decreases fhe melting point, enabling processing of the materials (e.g. 6 mol% propene 220°C) [35]. Semicrystalline ethylene/propylene/carbon mon- 

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