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:
Jan. 04, 2005
Filed:
Oct. 10, 2003
Thomas Redden Veariel, Houston, TX (US);
George Varcelia Yenetchi, Baytown, TX (US);
Sandy Clay Hinds, Crosby, TX (US);
Diwalker Singh, Singapore, SG;
Thierry Polchlopek, Bolbec, FR;
Thomas Redden Veariel, Houston, TX (US);
George Varcelia Yenetchi, Baytown, TX (US);
Sandy Clay Hinds, Crosby, TX (US);
Diwalker Singh, Singapore, SG;
Thierry Polchlopek, Bolbec, FR;
ExxonMobil Chemical Patents Inc., Houston, TX (US);
Abstract
The present invention is a process for transitioning from a first polymerization catalyst system to a second polymerization catalyst system incompatible with the first polymerization catalyst system in a gas-phase reactor. The novel process comprises conducting a first polymerization reaction using a first polymerization catalyst system; stopping the first polymerization reaction; removing the contents of the first polymerization reaction from the reactor while maintaining a substantially closed system; then, in the substantially closed system, introducing a substantially contaminant free seedbed into the reactor; introducing a second feed system and a second catalyst system into the reactor; and conducting a second polymerization reaction.