Methylaluminoxane(MAO)is the most commonly used activator for metallocenes in olefin polymerization reactions.In this research,an insoluble form of methylaluminoxane,also known as solid polymethylaluminoxane(sMAO),has been synthesized by the controlled hydrolysis of trimethylaluminum(TMA)with benzoic acid,followed by thermolysis.The role of preparing conditions(concentration of precursor,temperature of thermolysis,amount of hexane,et al.)on the particular morphology was sys-tematically explored.SEM,ICP-MS and PSDA were used to characterize sMAO particles.sMAO can be utilized to support metallocene pre-catalysts in slurryphase ethylene polymerization reactions.Metallocene pre-catalyst rac-ethylenebis(1-indenyl)dichlorozirconium,rac-(EBI)ZrCl2 were immobilized on sMAO samples,to afford solids which showed very high polymerization activities in hexane,comparable to those of the respective homogeneous catalysts formed by treatment of the pre-catalysts with MAO.
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