| In order to compose supported metallocene compounded catalyste,Four different ligands had been used in reaction with TiCU that supported on MgCla or spherical MgCb already.In this paper, the catalytic properties of ethylene polymerization and copolymerization activated by Methylalumoxane(MAO) and the structural characters of polymers obtained were studied.It proved that in these four different ligands,ligand of 2,3,5,8-tertramethylindene showed the highest activity.At the same time, the carrier of sepherical MgCl2 was better than that of MgCl2.Using these catalysts, high molecular weight of Mw more than one million and a narrow molecular distribution with Mw/Mn about 3-5 can be obtained.In the ethylene homopolymerization,the polymerization conditions were showed as follow:T=30 , Al/Ti=1000(mole ratio),[Ti]=8.63xlO~5mol/l.Whereas in the copolymerization of 1-hexene ,It was found that the comonomer effect was serious clear,especialy to the polymerization temperature .When T=50, Al/Ti=500(mole ratio),the copolymerization activity was the highest.The microstrcture of the copolymer were analyzed by means of 13C-NMR spectra. It was found that the average sequence length of 1-hexene was approximately one,and the copolymer was random.
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