Organohydridosiloxane resins with low organic content
US6218497A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1998 |
| Grant date | Apr 17, 2001 |
| Priority date | — |
| Expiry date | Mar 20, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An organohydridosiloxane polymer having a cage conformation, between approximately 0.1 to 40 mole percent carbon-containing substituent, and a dielectric constant of less than about 3.0 is disclosed. Each silicon atom of the cage polymer is bonded to at least three oxygen atoms and to either a hydrogen atom or an organic substituent. By providing such a caged structure having essentially no hydroxyl or alkoxy substituents, either on the polymer backbone or at terminal silicon atoms, essentially no chain lengthening polymerization can occur in solution. Such organohydridosiloxane resins having a molecular weight in the range from about 400 to about 200,000 atomic mass units were formed using a dual phase solvent system and either a solid phase or a phase transfer catalyst to assist the condensation of hydridotrihalosilane with at least one organotrihalosilane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.