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:
Sep. 09, 1997
Filed:
Mar. 05, 1996
Michael William Tilston, St. Albans, WV (US);
Thomas Edward Spriggs, Cross Lane, WV (US);
Union Carbide Chemicals & Plastics Technology Corporation, Danbury, CT (US);
Abstract
A process comprising contacting ethylene and at least one alpha-olefin comonomer having 3 to 8 carbon atoms with a transition metal based catalyst system in two fluidized bed reactors connected in series, in the gas phase, under polymerization conditions, with the provisos that: (a) the first reactor is operated at a temperature at or above the dew point of the mixture of monomers, but no higher than about 5 degrees C. above said dew point; (b) the mixture of ethylene copolymer matrix and active catalyst formed in the first reactor in the series is transferred to the second reactor in the series; (c) other than the active catalyst referred to in proviso (b), no additional catalyst is introduced into the second reactor; (d) in the reactor in which a low melt index copolymer is made: