Pyrolysis and combustion of cellulose. I. Effects of triphenyl phosphate in the presence of nitrogenous bases

Abstract

synopsisThe ability of selected phosphorus-containing compounds and nitrogen-containing compounds to act as flame retardants for cotton cellulose was investigated using flame tests, thermal gravimetric analysis (TGA), and differential thermal analysis (DTA). The effectiveness of the organophosphorus compounds was found to correlate with the changes which they induced in the pyrolytic degradation of the cellulose as indicated by DTA. Many of the samples containing nitrogen were found to exhibit DTA curves having pronounced exothenns. The presence of nitrogen-containing compounds in conjunction with the organophosphorus systems enhanced their ability to retard flame propagation but did not produce significant changes in t.he pyrolytic endotherm as observed by DTA. More conclusive evidence for a chemically based phosphorus-nitrogen synergism was obtained by the use of TGA. These data can be interpreted in terns of the phosphorusnitrogen synergistic effects and flame retardance mechanisms which have been proposed in the literature.

Effect of phosphorus and nitrogen on flame retardant cellulose: A study of phosphorus compounds

“…Similar kind of phenomenon was observed by Hendrix et al in their studies on organophosphorus flame retardant cellulose fabrics [8,9]. The first one at $240 8C was interpreted as phosphorylation of cellulose, and the second one at 250-310 8C was considered as acid catalyzed dehydration.…”

Thermal ignition behaviour of ammonium perchlorate in presence of fuel-rich compounds

“…Based on analogous results obtained in the decomposition of cellulose containing a low concentration of ammonium hydrogen phosphate [18], where an endotherm is observed at 240 ~ the endotherm at 220 ~ may be attributed to acidcatalysed depolymerization and decomposition. The acid in this case may result from the decomposition of AP.…”

Flame Retardant Finishing for Textiles

“…Combinations of nitrogen compounds such as urea or methylolmelamine with acids such as phosphoric acid produce, upon exposure to flame, intumescent chars which tend to protect the underlying combustible substrate, because of their good thermal insulating character. Elemental analyses of char residues show that effective N-P combinations leave a P-N-O-thermally stable amorphous substance, in the residue [21,22]. Nitrogen acids could also form an acid char and nitrogen oxides may act as flame free-radical traps in the vapor phase.…”