Process for synthesizing epoxidized polysulfides
US5173549A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1990 |
| Grant date | Dec 22, 1992 |
| Priority date | — |
| Expiry date | Jul 5, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G59/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An improved process for reacting a mercaptanterminated aliphatic polysulfide resin with excess epichlorohydrin in the presence of alkali to form an expoxidized polysulfide is disclosed. The reaction takes place in the absence of a solvent such as ethyl alcohol or ether, which will form an inseparable azeotrope with epichlorohydrin and water. The reaction is carried out at a temperature and pressure sufficient to distill away epichlorohydrin and by-product water. The water and epichlorohydrin are separated and the epichlorohydrin is returned to the pot during the reaction. After the reaction is complete, the epichlorohydrin is stripped, leaving an epoxidized polysulfide, by-product sodium chloride, and residual alkali. The epoxidized polysulfide is dissolved in a work-up solvent and filtered to remove sodium chloride and alkali. Then the work-up solvent is stripped, leaving a purified product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.