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A novel bis(α-alkyloxoimine) titanium(IV) complex was synthesized and used as a catalyst precursor to catalyze homo-and copolymerization of ethylene and norbornene.The titanium complex activated with methylalumoxane exhibits good activities for the homopolymerizations of ethylene and norbornene under high temperature to produce high-molecular-weight linear polyethylene and vinyl-type polynorbornene,respectively.Ethylene-norbornene copolymers with high molecular weight can also be produced by this catalyst.The incorporation of norbornene from 0 to 76 mol% in the copolymers can be controlled by varying the charged norbornene.13C NMR analyses show that the microstructures of the ethylene-norbornene copolymers with low norbornene incorporation are predominantly alternated and isolated norbornene units,while those with high norbornene incorporation are random polymers containing long norbornene sequences.
A novel bis (α-alkyloxoimine) titanium (IV) complex was synthesized and used as a catalyst precursor to catalyze homo-and copolymerization of ethylene and norbornene. Titanium complex activated with methylalumoxane exhibits good activities for the homopolymerizations of ethylene and norbornene under high temperature to produce high-molecular-weight linear polyethylene and vinyl-type polynorbornene, respectively.Ethylene-norbornene copolymers with high molecular weight can also be produced by this catalyst. The incorporation of norbornene from 0 to 76 mol% in the copolymers can be controlled by varying the charged norbornene. 13C NMR analyzes show that the microstructures of the ethylene-norbornene copolymers with low norbornene incorporation are predominantly alternated and isolated norbornene units, while those with high norbornene incorporation are random polymers containing long norbornene sequences.