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:
Jun. 25, 2002
Filed:
Apr. 06, 2000
Irwin L. Goldblatt, Edison, NJ (US);
Richard P Sauer, North Plainfield, NJ (US);
Castrol Limited, Swindon, GB;
Abstract
Methods for making graft copolymers include (a) providing (i) an ethylene/propylene 9EP) copolymer or other graftable polymer, (ii) an ethylenically unsaturated sulfur-, nitrogen- and/or oxygen-containing monomer, and (iii) an amount of an initiator sufficient to graft said monomer and EP copolymer or other graftable polymer, (b) introducing the EP copolymer or other graftable polymer into an extruder, (c) introducing the monomer into the extruder, (d) introducing the initiator into the extruder, wherein at least one of the reactants employed in step (a) is introduced in the presence of a polar solvent, and (e) reacting the EP copolymer or other graftable polymer, monomer and initiator by operating the extruder, thereby forming the graft copolymer. Methods of making dispersant viscosity index improver and methods for making a lubricating oil, as well as graft copolymers, viscosity index improvers and lubricating oils made by such methods are also contemplated.