US 4,540,720 A · Polyamines, a process for the production of polyamines and their use in the production of polyurethanes

Abstract

The invention relates to a simplified, economic process for the production of polyamines by the alkaline hydrolysis of compounds containing terminal aromatic and/or aliphatic isocyanate groups (including modified isocyanates or NCO-prepolymers and semi-prepolymers with NCO-contents of from 0.5 to 40% by weight), with strong aqueous bases, direct isolation of the polyamines from the carbamate stage being possible by thermal carbamate decomposition and/or solvent extraction. The invention also relates to the use of the aromatic and/or aliphatic polyamines containing primary NH.sub.2 -groups obtainable by the process according to the invention for the production of polyurethanes, such as optionally cellular polyurethane plastics and polyurethane foams.

Claims14

Dependent claims

A process for the production of aromatic and/or aliphatic, primary polyamines by the hydrolysis of compounds containing isocyanate groups, comprising

(I) converting aromatic and/or aliphatic compounds containing from 0.5 to 40% by weight of isocyanate groups into compounds containing carbamate groups by mixing said aromatic and/or aliphatic compounds with a strong aqueous base and at least a stoichiometric quantity of water and
(II) recovering polyamines directly from the compounds containing carbamate groups by thermal decomposition or by solvent extraction.

Dependencies are inferred from the claim text.

Polyamines, a process for the production of polyamines and their use in the production of polyurethanes

Life of this patent

Polyamines, a process for the production of polyamines and their use in the production of polyurethanes

Life of this patent

Abstract

Claims14