Citation

Bugajny M, Le Bras M, Bourbigot S. Fire Mater. 1999; 23(1): 49-51.

Copyright

(Copyright © 1999, John Wiley and Sons)

DOI

unavailable

PMID

unavailable

Abstract

This work studies a polypropylene/ammonium polyphosphate/polyurethane intumescent fire retardant material. It reports the foaming expansion under a normal strain and the variation of the apparent viscosity of the heat-treated material measured using a plate-plate rheometer, The loss of the protective character of the intumescent coating is discussed. It is proposed that it is related to a limited foaming expansion value, an increase of its apparent initial viscosity and a decrease of this viscosity with time when a normal force and a sinusoidal strain are both applied. The changes in the dynamic properties of the system are explained by the chemistry of the intumescence process.