Synthesis Of Base Oil Of Lubricant By Polymerizing Alpha-Olefin Catalyzed By Bridged Metallocene Catalytic System

With increasing quality demand of lubricant for mechanical equipments such as automobile engine, traditional mineral based lubricant has been difficult to meet the requirements. Poly alpha-olefin based lube oil has excellent performance such as ultra high viscosity index, strong antioxidant and corrosion resistance power. It becomes the best choice for the new generation lubricating based oil. In this paper,1-decene polymerization for lubricating based oil catalyzed by rac-Et（1-Ind）₂ZrCl₂/Al（ⁱBu）₃/[Me₂NHPh]⁺[B（C₆F₅）₄]^- was studied, effect of different reaction conditions on yield and products properties were discussed, the kinetics of 1-decene polymerization catalyzed with it were investigated and the impacts of four different metallocene system on the feature of polymerization were compared.The metallocene system rac-Et（1-Ind）₂ZrCl₂/Al（ⁱBu）₃/[Me₂NHPh]⁺[B（C₆F₅）₄]^-catalyzed 1-decene polymerization. When the feeding sequence is 1-decene, toluene, Al（iBu）3, metallocene, organic borate compound, Zr/1-decene molar ratio is 8x10-5, Al/Zr molar ratio is 80, reaction temperature is 80℃ and reaction time is 1 hour, the yield is 96.2%. The obtained polymer has excellent properties:kinematic viscosity at 100℃ is 390.23 mm²/s, viscosity index is 259, flash point is more than 300℃, pour point is -25℃, Mn is 6235, Mw is 13019, and the molecular weight distribution is 2.088.Through the investigation of kineties of polymerization of 1-decene over rac-Et（1-Ind）2ZrCl2/Al（iBu）3/[Me2NHPh]+[B（C6F5）4]- catalyst system, the results showed: when reaction temprature reached 323 K,333 K,353 K, the reaction ratio constant was 6407 L·mol^-1·h^-1,7551 L·mol^-1·h^-1,9771 L·mol^-1·h^-1, respectively. Fitting these date can get that the pre-exponential factor is 8118.41 L·mol^-1·h^-1 and the apparent activation energy is 12.18 KJ/mol.The 1-decene polymerization catalyzed with four different metallocene system were compared. The results showed that, compared the metallocene Ph₂C（Cp）（9-Flu）ZrCl₂ with rac-Et（1-Ind）₂ZrCl₂, the reaction activity was higher, the obtained polymer has higher molecular weight, viscosity and viscosity index and the lower vinylidene ratio of end group; compared the cocatalyst Al（ⁱBu）₃/[Me₂NHPh]+[B（C₆F₅）4]- with MAO, the reaction activity was higher, the obtained polymer has higher molecular weight, viscosity and viscosity index and the lower vinylidene ratio of end group.