Methods of making polysiloxanes
US5578692A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1996 |
| Grant date | Nov 26, 1996 |
| Priority date | — |
| Expiry date | Feb 5, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/38
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Linear or straight-chain trimethylsiloxy endcapped methylhydrogen polysiloxanes are made by contacting hexamethyldisiloxane with a highly pure methylhydrogen cyclic siloxane, in the presence of anhydrous trifluoromethane sulfonic acid catalyst at room temperature. Trimethylsiloxy endcapped alkylmethyl siloxanes are made by reacting the linear or straight-chain trimethylsiloxy endcapped methylhydrogen polysiloxanes with an alpha-olefin, in the presence of a platinum catalyst. Alkylmethyl cyclic siloxanes containing zero parts per million residual .tbd.SiH, are made by reacting anhydrous alpha-olefins and a highly pure methylhydrogen cyclic siloxane, in the presence of dried platinum supported on carbon catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.