A highly chlorinated xylene promoter for ethylene-propylene copolymerisation over a vanadium catalyst.

The regularities of ethylene-propylene copolymerisation over a vanadium oxytrichloride (VOCl)-ethylaluminium sesquichloride (EASC) catalytic system in the presence of hexachloro--xylene (HCPX), -butyl chloride, trichlorotoluene, hexachlorocyclopentadiene, and trichloroacetate were studied. The main kinetic regularities of ethylene-propylene copolymerisation when using HCPX were determined and the kinetic parameters of the process were obtained. It was shown that hexachloro--xylene is the most efficient promoter of polymerisation that increases activity of the "vanadium" catalyst severalfold and enhances propylene reactivity in its copolymerisation with ethylene.