Citation

Horrocks AR, Zhang S. Fire Mater. 2002; 26(4-5): 173-182.

Copyright

(Copyright © 2002, John Wiley and Sons)

DOI

unavailable

PMID

unavailable

Abstract

Phosphorylation of cellulose flame retarded with an ammonia-cured, polycondensed tetrakis(hydroxymethyl) phosphonium-urea derivative (as Proban CC(R), Rhodia) with a polyol diphosphoryl chloride or phosphorochloridate like spirocyclic pentaerythritol di(phosphoryl chloride) or diphosphorochloridate, SPDPC can yield phosphorus levels in excess of 10% (w/w). Such high levels suggest up to 82% yields of reaction if phosphorylation of the free secondary amine groups present in the cross-linked flame retardant is the assumed site. The presence of substituted pentaerythritol phosphate moieties significantly increases char formation above 400degreesC and scanning electron microscopy indicates that the char has an intumescent structure. The char-forming characteristic is not influenced by subjecting the phosphorylated flame retardant cellulose to boiling in a 1% detergent solution in water thereby suggesting that the product is durable. The potential of this reaction to create a durable, intumescent flame retardant for cellulose is discussed.