Patent · US Expired

Diamine recovery process

US4380615A · kind A · utility

4Cited by
7References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 5, 1981
Grant dateApr 19, 1983
Priority date
Expiry dateMar 5, 2001

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G69/28
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The efficiency of a rectifying zone for the recovery of diamine vapor from water vapor being separated from a reaction zone in which a polyamide-forming salt is being heated to form a prepolymer is improved by adding a dicarboxylic acid to the reflux water at the top of the rectifying zone.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.