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:
Dec. 24, 1991
Filed:
Feb. 11, 1988
Daniel C Durand, Battersea, GB;
Frederic R Morterol, Saussset-les-Pins, FR;
BP Chemicals Limited, London, GB;
Abstract
The present invention relates to a process for starting up the polymerization of ethylene or copolymerization of ethylene and at least one other alpha-olefin by bringing ethylene and optionally at least one other alpha-olefin in contact under fluidized-bed polymerization or copolymerization conditions and/or stirred mechanically, with a charge powder in the presence of a catalyst comprising a chromium oxide compound associated with a granular support and activated by thermal treatment, this catalyst being used in the form of a prepolymer, this process being characterized in that the charge powder employed is previously subjected to a treatment by contacting the said charge powder with an organo-aluminium compound, in such a way that the polymerization or copolymerization starts up immediately after the contacting of the ethylene and optionally one other alpha-olefin with the charge powder in the presence of the prepolymer.