Kinetic studies of the polymerization of ethylene using a novel Ziegler catalyst

The applied objective of this research was to prepare an ultra-high molecular weight polyethylene with improved physical properties more suited for use in surgical implants, especially artificial hip-joints, than those of current materials. A recently discovered Ziegler catalyst system involving aluminium alkyls and titanium (III) chloride prepared using a ifrignard reagent was used to obtain material of high molecular weight at very high levels of catalytic activity. Using this system, conditions have been established for preparing polymer of viscosity number 25 cm\(^3\)gm\(^-\)\(^1\) x 10\(^-\)\(^2\) (M\(_n\)~1.4 x 10\(^6\)) and titanium content 1 ppm compared with viscosity number 17 cm\(^3\)gm\(^-\)\(^1\) x 10\(^-\)\(^2\) and titanium content 10 ppm for the commercial material Hostalen GUR, The processes required for the unusually stringent purification of reagents necessary to obtain the benefit of the exceptional activity of the present catalyst system (employed down to very low concentrations: 1 x 10\(^6\) molar) are described