Copolymer composition in high pressure copolymerizations of ethylene with vinyl monomers

New Approaches in Polymerizations Using Transition Metal Complexes.

“…The polymerization using this initiator produced high-molecularweight polyethylene with rather small polydispersity. Higher catalytic activity (10 times higher) was observed when we employed the initiator [6-thiobis(2,4-di-tert-butylphenolate]VOCl2 (43) and (N,N'-di-tert-butyl-1,1'-binaphtyl -2 ,2'-diamino)VOCl2 (44) in place of complex 42 and 42 43 44 45 (N-tert-butylimino-Me2Si-2,3,4,5-tetramethylcyclopentadienyl)VOCl (45) ( Figure 12, Table 9). Although complexes 44 and 45 conducted the polymerization of MMA in only low yield, the block copolymerization of ethylene with MMA gave the desired copolymer as evidenced by the 1H NMR spectrum, although random copolymerization of ethylene with MMA did not proceed.…”