Ethylene Polymerization by Cp2ZrCl2-B(C6F5)3-Tea Catalyst System Using Low Al/Zr Ratio
نویسندگان
چکیده
Ethylene polymerization by Cp2ZrCl2-B(C6F5)3-TEA catalyst system using low Al/Zr ratio has been studied with varying ethylene pressure, catalyst concentration, Al/Zr ratio, and reaction temperature. The study showed that there was an optimum condition for each variable at which maximum productivity was obtained. It was proposed that there were two competing reactions, the catalyst activation and deactivation, taking place simultaneously. The maximum productivity of 3133 kgPE/mole-Zr.atm.h was obtained using 3 mmol each of zirconocene and borane, and a Al/Zr ratio of 300 at 30 °C. The crystallinity of the product was obtained using DSC and its morphology was studied by SEM.
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