Method of polymerizing oligomers of polydiorganosiloxane in the presence of filler
US4448927A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1983 |
| Grant date | May 15, 1984 |
| Priority date | — |
| Expiry date | Mar 14, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Oligomers of low molecular weight polydiorganosiloxanes, polydiorganocyclosiloxanes, or mixtures are polymerized in the presence of acidic or neutral reinforcing fillers. Trifluoromethane sulfonic acid is used as the polymerization catalyst. The method can also include endblocked polydiorganosiloxane to control the molecular weight of the silicone polymer in the silicone polymer-filler produced. The method combines the oligomer and filler, heats to from about 70.degree. to 150.degree. C., adds catalyst, adjusts temperature, and polymerizes the mixture, then inactivates with a Lewis base such as calcined magnesium oxide. The non-crepeing silicone polymer-filler mixture which is the product of the method is usable as electrical insulation grease, or as a reinforced polymer mixture useful in producing silicone elastomers. The mixture can be mixed with curing agents to produce heat curable and moisture curable elastomeric compositions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.