Process for the preparation of carbonic acid esters
US4327035A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 1980 |
| Grant date | Apr 27, 1982 |
| Priority date | — |
| Expiry date | Jan 17, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G64/38
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a process for the preparation of carbonic acid esters of monoalcohols or polyalcohols, which is characterized in that ureas are reacted with monoalcohols or with polyalcohols in the molar ratio of at least 1:2, in the presence of a catalyst, at reaction temperatures between 120.degree. C. and 270.degree. C. Accordingly, the present invention also relates to a process for the preparation of oligocarbonates and polycarbonates, which is characterized in that ureas are reacted with primary dialcohols in the molar ratio of about 1.5:1 to about 1:1.5, together with monoalcohols, in the presence of catalysts at reaction temperatures between 120.degree. C. and 270.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.