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:
Aug. 08, 1978
Filed:
Mar. 23, 1977
Adrien Nicco, Bethune, FR;
Jean-Pierre Machon, Bethune, FR;
Societe Chimique des Charbonnages-CdF Chimie, Mazingarbe, FR;
Abstract
Ethylene is polymerized, in the presence of hydrogen, at a temperature of 180.degree. to 340.degree. C and a pressure of 200 2,500 bars with a Ziegler catalyst in a stirred reactor having at least one first reaction zone and at least one second reaction zone. The reaction mixture is fed to a separator at a pressure of 80 to 400 bars. The improvement results from partially liquifying at least a part of the gas coming from the separator at a temperature of -50.degree. to +20.degree. C, releasing the pressure to a value of 10 to 60 bars, separating the partially liquified gas into a gas phase and a liquid phase, and recycling the gas phase to the second reaction zone and the liquid phase to the first reaction zone. The resulting polymer has a low melt index, a high polydispersity index, and superior physical properties compared to polymers prepared by conventional processes.