ETHYLENE POLYMER, SOLID TITANIUM CATALYST COMPONENT FOR ETHYLENE POLYMERIZATION, ETHYLENE POLYMERIZATION CATALYST COMPRISING THE CATALYST COMPONENT AND PROCESS FOR PREPARING THE ETHYLENE POLYMER USING THE CATALYST

摘要

An ethylene polymer having small values of Mw/Mn andMz/Mw, a small proportion of long-chain branches, a highmelt tension and a high swell ratio, and a process forpreparing the ethylene polymer are disclosed.A solid titanium catalyst component obtained byinitially bringing a solid titanium composite which isobtained by the contact of a solid magnesium aluminumcomposite containing magnesium, halogen, aluminum, and analkoxy group of 6 or more carbon atoms and/or alcohol of 6or more carbon atoms with a tetravalent titanium compoundinto contact with an organometallic compound, and thenbringing the resulting product into contact with oxygen isfurther disclosed. An ethylene polymerization catalystcomprising the above catalyst component and anorganometallic compound catalyst component is furthermoredisclosed.Therefore, the ethylene polymer is excellent inmoldability, and a molded article obtained therefrom isexcellent in rigidity and impact resistance and free frompoor appearance.