Process for the preparation of di- and polyamines of the diphenylmethane series
AssigneeBayer MaterialScience AG
InventorsTorsten Hagen, Stefan Grabowski, Richard Adamson, Daniel Koch, Stefan Wershofen
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Abstract
Di- and polyamines of the diphenylmethane series are prepared by a) mixing a first portion of aniline with an acid catalyst, b) mixing a second portion of aniline with formaldehyde, and c) mixing and reacting the mixtures prepared in each of steps a) and b). The diamines produced by this process may then be phosgenated to produce the corresponding di-/polyisocyanate.
Claims8
A process for the preparation of a di- and/or polyamine of the diphenylmethane series comprising:
- a) mixing a first portion of aniline with an acid catalyst to form a first mixture,
- b) mixing a second portion of aniline with formaldehyde to form a second mixture,
- c) mixing the mixture of step a) with the mixture of b) to form a third mixture, and
- d) reacting the mixture of step c) to form a di- and/or polyamine of the diphenylmethane series.
A process for the preparation of a di- and/or polyisocyanate of the diphenylmethane series comprising:
- a) mixing a first portion of aniline with an acid catalyst to form a first mixture,
- b) mixing a second portion of aniline with formaldehyde to form a second mixture,
- c) mixing the mixtures prepared in step a) and b) with one another to form a third mixture,
- d) reacting the mixture from c) to form a di- and/or polyamine of the diphenylmethane series, and
- e) phosgenating the di- and polyamines of the diphenylmethane series formed in step d) to form a di- and/or polyisocyanate of the diphenylmethane series.
Dependencies are inferred from the claim text.