THE EFFECT OF SILICA PORE VOLUME ON ETHYLENE / 1-HEXENE COPOLYMERIZATION USING SUPPORTED ZIEGLER-NATTA CATALYST

Three different types of silica MS3030, EP41, and ES70 having different pore diameter, pore volume and particle size were used to support titanium tetrachloride catalysts for ethylene and 1-hexenecopolymerization at various hydrogen pressures. The type of silica support was found to influence the catalyst activity and the copolymer properties such as molecular weight, molecular weight distribution,comonomer incorporation and density.The catalyst activity increased when the silica support pore volume’s increased. However, the shapes ofthe rate-time profiles were the same.Polymer molecular weight increased as the silica supports pore volume increased. Hydrogen in general reduced the polymer molecular weight and caused broadening to the molecular weight distribution of the produced polymer. However, great reduction in polymer molecular weight was achieved when using silicasupport with small pore.The comonomer incorporation mol and weight percentages of produced polymers were increased as the silica support pore volume increased. Accordingly, the densities of the produced polymers were decreased as the silica support pore volume increased.