| abstract |
A solution process for the preparation of high molecular weight homopolymers of ethylene and copolymers of ethylene and C3-C12 alpha -olefins is disclosed. The process involves feeding monomer, a particlar coordination catalyst and hydrocarbon solvent to a reactor, polymerizing the monomer at a temperature of 100 DEG -320 DEG C. and recovering the polymer. The catalyst is obtained by either (i) combining solutions of titanium tetrahalide/vanadium oxytrihalide and of organoaluminum compound at a temperature of less than 30 DEG C., heating the resulting admixture to a temperature of 150 DEG -300 DEG C. for a period of 5 seconds to 60 minutes and combining the thus heat-treated mixture with a solution of an organoaluminum compound or (ii) combining solutions of titanium tetrahalide and of organoaluminum compound at a temperature of less than 30 DEG C., heating the resultant admixture to a temperature of 150 DEG -300 DEG C. for a period of 5 seconds to 60 minutes, combining the thus heat-treated mixture with vanadium oxytrihalide and then combining the mixture so obtained with a solution of an organoaluminum compound. The catalyst thus obtained is fed to the process, without separation of any compounds of the catalyst. |