Process for the preparation of polyamines

  • US 4,147,724 A
  • Filed: 12/17/1976
  • Issued: 04/03/1979
  • Est. Priority Date: 12/19/1975
  • Status: Expired due to Term
First Claim
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1. A process for the preparation of multinuclear aromatic polyamines by condensation of aromatic amines with formaldehyde in the presence of aqueous acid catalysts in a condensation reaction carried out in at least two stages, followed by neutralization of the catalyst and recovery of aromatic polyamines, characterized in that free amine is removed from the condensation reaction mixture by means of a hydrophobic solvent after the first condensation stage and before the final condensation stage, and the amine thus removed is returned to the aqueous, catalyst-containing phase by returning the resulting amine-containing solvent phase to said aqueous phase before the first condensation stage.

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