Polar grafted polyolefins, methods for their manufacture, and lubricating oil compositions containing them
US5874389A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 1997 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Aug 29, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/28
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A grafted polyolefin containing one or more of N-vinylimidazole, 4-vinylpyridine, or other ethylenically-unsaturated nitrogen-containing or oxygen-containing graftable monomers grafted to a polyolefin copolymer is disclosed. The grafted polyolefin preferably has a weight average molecular weight of from about 20,000 to about 500,000, a polydispersity of less than about 10, and an ADT value of at least about 8. The grafted polyolefin can be defined as containing more than about 1.2% by weight of grafted monomer on a polyolefin, or as containing at least about 13 moles of graftable monomers per mole of polyolefin, or as having an asphaltene dispersancy test (ADT) value of at least about 8. 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 graftable monomers and a graftable polyolefin are reacted with enough of an initiator to graft the monomer to the polyolefin. The initiator and/or graftable monomer is added to the other ingredients, maintained at the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.