End-capped multifunctional viscosity index improver
US5035821A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 18, 1988 |
| Grant date | Jul 30, 1991 |
| Priority date | — |
| Expiry date | Jul 18, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10M2217/06
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Oil soluble viscosity index improvers-dispersants exhibiting improved cold temperature viscometric properties, and Thickening Efficiencies and Shear Stability Indexes generally similar to conventional V.I.-dispersants, comprised of the reaction products of (i) ethylene copolymer, such as copolymer of ethylene and propylene, grafted with ethylenically unsaturated carboxylic acid moieties, preferably maleic acid or anhydride moieties; (ii) polyamine having two or more primary amino groups or polyol; (iii) an amount effective to provide a V.I. improver-dispersant exhibiting improved cold temperature viscometric properties of a high functionality long chain hydrocarbyl substituted dicarboxylic acid material such as alkenyl succinic anhydride, preferably polybutene succinic anhydride, having a functionality of at least 1.2, preferably at least about 1.3, and more preferably at least 1.4; and (iv) a molecular weight stabilizing effective amount of a short chain hydrocarbyl substituted dicarboxylic acid or anhydride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.