Laddery lower alkylpolysilsesquioxane having heat-resistant thin film-formability and process for preparing same
US4399266A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1982 |
| Grant date | Aug 16, 1983 |
| Priority date | — |
| Expiry date | Mar 2, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G77/32
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A laddery lower alkylpolysilsesquioxane represented by the formula: ##STR1## wherein R and R' represent same or different lower alkyl groups, and n represents an average degree of polymerization, said laddery lower alkylpolysilsesquioxane having a heat-resistant thin film-formability, characterized in that 15 to 30% by weight of the lower alkylpolysilsesquioxane is occupied by the portion having a standard polystyrene-reduced molecular weight of 20,000 or less as measured by gel permeation chromatography. Said silicone resin in which R and R' are methyl is prepared by dissolving CH.sub.3 SiCl.sub.3 in a ketone or an ether, adding water to this solution with stirring to hydrolyze CH.sub.3 SiCl.sub.3, condensing the hydrolyzate and, if necessary, subjecting the resulting condensate to a treatment for adjusting the proportion of the low molecular weight portion in the product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.