Viscosity improvers for lubricating oil-compositions
US6271184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2000 |
| Grant date | Aug 7, 2001 |
| Priority date | — |
| Expiry date | Jun 30, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2030/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A copolymer comprising units derived from (a) methaciylic acid esters containing from about 9 to about 25 carbon atoms in the ester group and (b) methacrylic acid esters containing from 7 to about 12 carbon atoms in the ester group, said ester groups having 2-(C.sub.1-4 alkyl)-substituents, and optionally (c) at least one monomer selected from the group consisting of methacrylic acid esters containing from 2 to about 8 carbon atoms in the ester group atoms and which are different from methacrylic acid esters (a) and (b), vinyl aromatic compounds, and nitrogen-containing vinyl monomers with the proviso that no more than 60% by weight of the esters contain not more than 11 carbon atoms in the ester group. Also described are additive concentrates and lubricating oil compositions containing the copolymers and processes for preparing copolymers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.