Comb graft polymers and their use in functional fluids
US5508353A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 1994 |
| Grant date | Apr 16, 1996 |
| Priority date | — |
| Expiry date | Aug 3, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F257/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
There are disclosed novel comb graft polymers and copolymers comprising a backbone of a linear polymer of p-methylstyrene (p-MS) and grafted branches of a linear addition polymer of at least one anionically polymerizable compound. The polymers may be produced by metallating the p-MS polymer with an organo alkali metal metallating agent, e.g., an alkyllithium, at active hydrogen sites along the polymer chain and graft polymerizing the anionically polymerizable compound at the metallated sites to form the grafted branches. Certain of the foregoing comb graft polymers and copolymers, e.g., wherein the backbone is a homopolymer of p-MS or a copolymer of p-MS and a ring-substituted alkylstyrene such as p-tert-butylstyrene (t-BS) and the branches are a polymer of t-BS, are useful as additives to functional fluids, particularly hydrocarbon lubricating oils, for the purpose of thickening and improving their viscosity index.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.