Synthesis Of Ultra High Viscosity Index Poly-alpha-olefin Catalyzed By Metallocene Catalytic System

The ultra high viscosity index poly-alpha-olefin can be applied at tough condition such as heavy load and powerful shear. Metallocene catalytic system is an ideal catalyst for alpha-olefin polymerization because of their extra high activity and single active center. Its products have excellent performance because of their comb structure. In this paper, polymerization of1-decene catalyzed by metallocene activated by organic boride or MAO was studied, and the reaction mechanism of catalytic system was proposed. Effects of technological conditions on polymer properties were investigated, and polymer properties produced by different catalytic system were compared.The conversion rate of1-decene catalyzed by Rac-Et(l-Ind2ZrCl2/MAO system is91.62%when Zr/1-decene molar ratio is8x10-5. Al/Zr molar ratio is100, reaction temperature is50℃and reaction time is60min. The obtained polymer has excellent performance: kinematic viscosity at100℃is393.93mm2/s, viscosity index is271, Mn is9x103, and molecular weight distribution is1.69.The conversion rate of1-decene catalyzed by Ph2C(Cp-9-Flu)ZrCl2/MAO system is92.1%when Zr/1-decene molar ratio is9x10-?. Al/Zr molar ratio is120, reaction temperature is60℃and reaction time is50min. The obtained polymer has excellent performance: kinematic viscosity at100℃is2325.75mm2/s, viscosity index is349, Mn is2x104, and molecular weight distribution is1.72.The conversion rate of1-decene catalyzed by Ph:C(Cp-9-Flu)ZrCl2/C6H5NH(CH3)2B(C6H5)4/Al(’Bu)3system is93.6%when Zr/1-decene molar ratio is1x10-4, Al/Zr molar ratio is100, B/Zr molar ratio is1.5, reaction temperature is60℃and reaction time is120min. The obtained polymer has excellent performance:kinematic viscosity at100℃is3684.59mm2/s, viscosity index is367, Mn is2.9×104. molecular weight distribution is1.85.