Silicone polymer termination
US4766191A · kind A · utility
7Cited by
5References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1987 |
| Grant date | Aug 23, 1988 |
| Priority date | — |
| Expiry date | Jul 10, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polydiorganosiloxane gum, of the type produced by the alkaline metal catalyzed polymerization of organocyclosiloxanes can be reduced in hydroxyl content by mixing the gum with an acid or acid producing phosphoric component and a silylamine component, allowing the mixture to react until the hydroxyl groups are lowered to the desired extent, then devolatilizing the gum. The hydroxyl content can be lowered without causing any significant change in the molecular weight of the gum. The hydroxyl content can be lowered to essentially zero.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.