Gel-free process for making hydrogenated functionalized anionically polymerized polymers
US6242537A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1999 |
| Grant date | Jun 5, 2001 |
| Priority date | — |
| Expiry date | Mar 2, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F8/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention relates to a gel-free process for making hydrogenated functionalized polymers that mitigates the problem of ionic gel. When multi-alkali metal initiators are used to make these polymers anionically, the process comprises anionically polymerizing at least one monomer with a multi-alkali metal initiator, usually a lithium alkyl, in a hydrocarbon solvent, capping the polymer by adding to the polymer a capping agent that reacts with the ends of the polymer chains such that strongly associating chain ends are formed wherein a strongly associating polymer gel is formed, adding a trialkyl aluminum compound to the polymer gel, whereby the gel dissipates, optionally terminating the polymerization by addition of an alcohol, washing the polymer with aqueous acid, preferably aqueous mineral acid, most preferably phosphoric acid, wherein there is at least one mole of phosphoric acid per mole of alkali metal and at least three moles of phosphoric acid per mole of aluminum, and hydrogenating the polymer with a hydrogenation catalyst. In a second embodiment, the present invention relates to a process for making such polymers which comprises anionically polymerizing them as described…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.