Process for the production of polyamines
US3996283A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 30, 1973 |
| Grant date | Dec 7, 1976 |
| Priority date | — |
| Expiry date | Jul 30, 1993 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/3225
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An improved process for the production of multi-nuclear aromatic polyamines by condensing an aromatic amine with formaldehyde in the presence of an acid catalyst, obtaining the condensation product in an aqueous medium and then extracting the aqueous condensation mixture with a hydrophobic solvent in order to obtain a solvent phase and a separate aqueous phase. Thereafter polyamine product is recovered from the solvent phase. If desired, polyamine product can be obtained from both the solvent phase and the aqueous phase. Alternatively, the aqueous phase can be recycled to the initial condensation step, thus providing a continuous process without loss of acid catalysts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.