Process for making pulverulent ammonium polyphosphates stable to hydrolysis

US4639331A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Georg Elsner · Hürth, DE
• Horst Staendeke · Lohmar, DE
• Gero Heymer · Lechenich, DE

Key dates

• Filing date: Apr 23, 1984
• Grant date: Jan 27, 1987
• Expiry date: Apr 23, 2004

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S521/907
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The disclosure relates to a process for making a particulate agent stable to hydrolysis based on free-flowing, pulverulent ammonium polyphosphate by treating the ammonium polyphosphate with a thermosetting, artificial resin being water-insoluble when cured. More specifically, the disclosure provides for the ammonium polyphosphate, an aliphatic alcohol as a diluent, and a melamine/formaldehyde-resin or phenol/formaldehyde-resin to be placed in an autoclave and intimately mixed at room temperature; for the mixture to be heated to a temperature of about 80.degree. to about 180.degree. C. and allowed to remain over a period of 15 to 240 minutes at that temperature and under the pressure corresponding to the vapor pressure of the diluent; for the diluent to be separated and for the product so obtained to be dried.