The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 04, 2003
Filed:
Jun. 30, 2000
Mitsui Chemicals, Inc., Tokyo, JP;
Abstract
A process for preparing an ethylene/&agr;-olefin copolymer, which includes the steps of (A) copolymerizing ethylene and an &agr;-olefin of 3 to 20 carbon atoms by continuous vapor phase polymerization; (B) copolymerization is conducted in the presence of a prepolymerized catalyst obtained by prepolymerizing an olefin in the presence of (a) a transition metal compound, (b) an organoaluminum oxy-compound, (c) a fine particle carrier, and optionally (d) an organoaluminum compound; and (C) copolymerization is conducted under such condition that the partial pressure of sum total of ethylene and &agr;-olefin is 10 to 28 kg/cm . The resulting ethylene/&agr;-olefin copolymer has the following properties: (i) the density is in the range of 0.880 to 0.960 g/cm , (ii) the melt flow rate of 190° C. under a load of 2.16 kg is in the range of 0.1 to 100 g/10 min, (iii) the melt tension (MT (g)) at 190° C. and the melt flow rate (MFR (g/10 min)) satisfy the relation MT≦2.2×MFR .