Coordination Homopolymerisation and

1 Coordination Homopolymerisation and Copolymerisation of Functionalised a-Olefins with Ethylene and a-Olefins 

The use of borane-containing monomers clearly presents an effective and general approach in the functionalisation of polyolefins, which has the following advantages stability of the borane moiety to coordination catalysts, solubility of borane compounds in hydrocarbon solvents (such as hexane and toluene) used as the polymerisation medium, and versatility of borane groups, which can be transformed to a remarkable variety of functionalities as well as to free radicals for graft-form polymerisations. The functionalised polymers are very effective interfacial modifiers in improving the adhesion between polyolefin and substrates and the compatibility in polyolefin blends and composites [518], 

Advances towards the goal of polymerising polar monomers with coordination catalysts have been made with metallocene-based catalysts, especially aluminium-free cationic metallocene catalysts such as [Cp 2ZrMe]+[B(C6 Fs)4] or [Cp 2ZrMe]+[MeB(C6F5)3p. Waymouth et al. [500] found these 

Functionalised a-olefins capable of undergoing insertion polymerisation with Ziegler-Natta catalysts are, in principle, monomers in which the heteroatom (X) does not electronically interact with the double bond to be polymerised in such monomers, the heteroatom is separated from the double bond CH2=CH-(CH2)x X [326,384,518,522-528], Monomers with the heteroatom directly bound to the double bond, i.e. those of the CH2=CH-X type, may also undergo polymerization, but when the heteroatom is silicon or tin (X= Si, Sn) [522-526], Representative examples of the insertion polymerisation of functionalised a-olefins and their copolymerisation with ethylene and a-olefins in the presence of heterogeneous Ziegler-Natta catalysts are shown in Table 3.7 [2,241,326,384,518,522-528], 

Halogen-containing monomers can undergo insertion polymerisation only when the halogen atom is situated far away from the C=C bond this concerns co-halo-a-olefins [527]. 

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