Polar grafted polyolefins, methods for their manufacture, and lubricating oil compositions containing them
US5663126A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 10, 1995 |
| Grant date | Sep 2, 1997 |
| Priority date | — |
| Expiry date | Oct 10, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/28
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A grafted polyolefin containing N-vinylimidazole, 4-vinylpyridine, or other ethylenically-unsaturated nitrogen- or oxygen-containing graftable monomers grafted to a polyolefin copolymer. The grafted polyolefin preferably 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 contain more than about 1.2% by weight of grafted monomer or 13 or more moles of graftable monomers per mole of polyolefin and have an asphaltene dispersancy test (ADT) value of at least about 8. Also described is a lubricating oil comprising such a grafted polyolefin. Also described is a method of making a grafted polyolefin dispersant viscosity index improver by adding the graft monomer or the initiator slowly during the reaction. The present reaction can optionally be carried out by providing a melted reactant composition in an extruder or other polymeric mixer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.