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:
Mar. 30, 2010
Filed:
May. 09, 2006
Gabriele Mei, Ferrara, IT;
Joachim T. M. Pater, Ferrara, IT;
Gerben Meier, Frankfurt am Main, DE;
Pietro Baita, Rovigo, IT;
Gabriele Mei, Ferrara, IT;
Joachim T. M. Pater, Ferrara, IT;
Gerben Meier, Frankfurt am Main, DE;
Pietro Baita, Rovigo, IT;
Basel Poliolefine Italia s.r.l., Milan, IT;
Abstract
A process for the gas-phase polymerization of α-olefÊns CH═CHR, where R is hydrogen or a hydrocarbon radical having 1-12 carbon atoms, carried out in a first and a second interconnected polymerization zones, wherein the growing polymer particles flow through the first of said polymerization zones (riser) under fast fluidization conditions, leave said riser and enter the second of said polymerization zones (downcomer) through which they flow downward in a densified form, leave said downcomer and are reintroduced into said riser, in which process: (a) the gas mixture present in the riser is totally or partially prevented from entering the downcomer, and (b) the gaseous composition inside a portion of the downcomer is maintained substantially similar to the gaseous composition reacting in the riser.