Author/Authors :
ahmadjo, saeid iran polymer and petrochemical institute (ippi) - dapartment of catalyst, tehran, iran , arabi, hassan iran polymer and petrochemical institute (ippi) - dapartment of catalyst, tehran, iran , zohuri, gholam ferdowsi university of mashhad - faculty of science - department of chemistry, mashhad, iran , nejabat, gholam-reza iran polymer and petrochemical institute (ippi) - dapartment of catalyst, tehran, iran , omidvar, mojtaba iran polymer and petrochemical institute (ippi) - dapartment of catalyst, tehran, iran , ahmadi, mostafa amirkabir university of technology - department of polymer engineering and color technology, tehran, iran , mortazavi, mohammad mahdi iran polymer and petrochemical institute (ippi) - dapartment of catalyst, tehran, iran
Abstract :
bis(2-r-ind)zrcl2 (r: h or phenyl) was supported on different types of silica by in situ impregnation method and used for ethylene polymerization. in this method, the step of catalyst loading on support was eliminated and common alkyl aluminum (triisobutylaluminum, tiba) cocatalyst was used instead of expensive methyl aluminiumoxane (mao) cocatalyst in the polymerization. the effect of surface area of silica on the performance of the supported catalysts using three different types of silica including ep12 (390 m^2/gr.), pq3060 (570 m^2/gr.) and mcm-41 (1100 m^2/gr.) was investigated. the surface area had a more critical role relative to other characteristics of the support in the performance of catalysts. by using mcm-41 as support, the kinetic stability was enhanced. the activity of the supported catalysts was increased by increasing the surface area of silica in the order of mcm-41 pq3060 ep12. the morphology of polymer particles was improved and reactor fouling was eliminated by supporting the catalyst
Keywords :
in situ impregnation , heterogeneous catalysis , metallocene , polyethylene , silica
