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. 04, 1996
Filed:
Oct. 21, 1994
Frederick J Boden, Somerset, NJ (US);
Richard P Sauer, North Plainfield, NJ (US);
Irwin L Goldblatt, Edison, NJ (US);
Michael E McHenry, Washington, NJ (US);
Castrol Limited, Swindon, GB;
Abstract
A grafted polyolefin containing at least about 13 moles of N-vinylimidazole or other ethylenically-unsaturated nitrogen-containing and/or oxygen-containing monomers per mole of a grafted polyolefin backbone is disclosed. The graft polyolefin has a weight average molecular weight of from about 20,000 to about 500,000 and a polydispersity of less than about 10. The grafted polyolefin can alternatively be defined as containing more than about 1.2% by weight of grafted monomer on a polyolefin. Also described is a lubricating oil comprising a lubricant base oil and a grafted polyolefin as described above. Also described is a method of making a dispersant-viscosity index improver. N-vinylimidazole or other ethylenically unsaturated nitrogen-containing and/or oxygen-containing monomers and a graftable polyolefin are reacted with enough of an initiator to graft at least about 13 moles of the monomer to each mole of the polyolefin.