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. 24, 1992
Filed:
Oct. 17, 1988
Mitsui Toatsu Chemicals, Incorporated, Tokyo, JP;
Abstract
Disclosed herein is a method for controlling the molecular weight of a propylene homo- or co-polymer at a constant level upon subjecting propylene alone or a mixture of propylene and another .alpha.-olefin copolymerizable with propylene as a monomer or monomer mixture to bulk polymerization in the presence of hydrogen as a molecular weight modifier in a reaction tank equipped with a reflux condenser. According to the present invention, it is possible to prepare continuously a propylene homo- or copolymer, the molecular weight of which is controlled at a desired level, by measuring moment by moment the quantity of heat removed from the reaction tank, calculating the amount of the monomer or monomer mixture polymerized in the reaction tank based on the thus-calculated quantity, determining in advance the relationship between molecular weights and the volumes of hydrogen consumption required per unit amounts of corresponding polypropylene homo- or co-polymers, calculating the volume of hydrogen which is to be introduced into the reaction tank so as to obtain polypropylene of a desired molecular weight from the above relationship and the above-calculated polymerized amount, and charging hydrogen into the reaction tank in accordance with the above-calculated volume of hydrogen which varies from time to time.