Study On The Preparation Of Alkoxy Magnesium Supported Ziegler-Natta Catalyst And Polymerization Of Ethylene

The treatment of magnesium with alcohol manufactured alkoxy magnesium particles with good morphology, alkoxy magnesium reacted with transition metal halide preparation olefin polymerization catalyst with high activity. Compared to the MgCl2support, the preparation technology of Mg(OR)2support was simple,and could control the particle size of support. This work started from the reaction of magnesium powder and ethanol, prepared Mg(OEt)2supports, and then the Mg(OEt)2supports reacted with TiCl4preparation effective ethylene polymerization Ziegler-Natta catalysts. We discussed the effects of basic preparation conditions of Mg(OEt)2supports, dispersant and SiCl4on the properties of supports, studied the best preparation conditions of catalysts, as well as investigated the catalytic activity, polymerization kinetics and hydrogen regulation performance of the catalyst.This work realized the control of particle size and crystallization property of Mg(OEt)2supports. Under the conditions of adding magnesium for five times, ethanol/magnesium mole ratio was20, support preparation temperature was80℃, I2/magnesium mole ratio was0.0050, the Mg(OEt)2supports possessed the average particle size D(50) with53.3μm, bulk density with0.27g/cm3,crystallinity with14.8%; added decane and decane/ethanol mole ratio was0.3, the Mg(OEt)2supports had the average particle size D(50) with28.5μm, bulk density with0.36g/cm3, crystallinity with7.2%; SiCl4and Mg(OEt)2supports could happen chlorination reaction, when Si/Mg mole ratio was0.1, the Mg(OEt)2supports owned the average particle size D(50) with17.7μm, bulk density with0.38g/cm3, and had no crystallization behavior. We also used ICP, FTIR and SEM measured the Mg%, structure and morphology of the Mg(OEt)2supports.The best preparation conditions of catalysts were dropping TiCl4at-10℃, reacting with TiCl4at80℃and adding20ml TiCl4(1g Mg(OEt)2). Mg(OEt)2supports had differents average particle size D(50) and crystallization property could prepared catalysts respectively had differents Ti%, such as4.2%、5.0%and6.2%. The catalyst, which existed the Ti content of6.2%, catalyzed ethylene polymerization showed high activity of17700g PE/g Cat, smooth and steady polymerization kinetics curve and sensitive hydrogen regulation performance.When P(H2):P(C2H4)=28:45, the PE melt index(MI) was0.69g/10min, as well as P(H2):P(C2H4)=73:27, the PE MI was158.52g/10min. We also used SEM、WAXD、FTIR、13C GPC measure the particle morphology, crystallization property, microstructure, molecular weight and molecular weight distribution.