Forming clear gel and transparent film by reacting alumina hydrate with vinyl alcohol-vinyl acetate copolymer
US4785049A · kind A · utility
10Cited by
4References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1987 |
| Grant date | Nov 15, 1988 |
| Priority date | — |
| Expiry date | Jul 27, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K3/22
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A stable gel is formed by reacting alumina hydrate sol and a vinyl alcohol-vinyl acetate copolymer in an aqueous solution having pH less than about 7 to form a polymeric sol and then transforming the sol to a gel. The copolymer preferably comprises polyvinyl acetate that is about 85-99% hydrolyzed. The gel is drawn into a thin layer and water is removed to form a thin, substantially crack-free film. The film makes a stable, generally transparent insulating material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.