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:
Apr. 09, 1991
Filed:
Sep. 08, 1988
John B Gardiner, Mountainside, NJ (US);
Anthony A Loffredo, Westfield, NJ (US);
ricardo Bloch, Scotch Plains, NJ (US);
Nicholas C Nahas, Chatham, NJ (US);
Keith U Ingold, Ottawa, CA;
Theodore V Kowalchyn, Scotch Plains, NJ (US);
Exxon Chemical Patents, Inc., Linden, NJ (US);
Abstract
The molecular weight and the thickening efficiency of primarily oil soluble hydrocarbon polymers, such as hydrogenated random copolymers and block copolymers of styrene-isoprene or styrene-butadiene, polyisobutylene, poly-n-butene, low unsaturation butyl rubbers, low unsaturation EPDM rubbers, preferably ethylene-propylene copolymers, of the type which are to be used as viscosity index improver additives or as precursors for dispersants and multi-functional viscosity improver additives for lubricating oils, are reduced by heating and masticating the polymers in the presence of oxygen or air and in the presence of a transition metal catalyst, preferably in the further presence of a peroxide accelerator.