Possible phosphorus-bromine synergy in polyester-cotton fabrics treated with tetrabromobisphenol-A and diammonium phosphate

Polyester/cotton fabrics were treated with tetrabromobisphenol-A (TBBA)/epichlorohydrin (EPI) aqueous solution, followed by being treated with diammonium phosphate (DAP)/urea solution. The optimum mole ratio of EPI to TBBA was determined. The synergism of TBBA and DAP was found to operate on the treated fabrics. The maximal synergism was obtained when the bath concentration of TBBA was equal to that of DAP. The mechanism of flame-retardancy was analyzed by thermogravimetry and residue number. The flame-retardancy of the polyester/cotton fabrics treated with TBBA/DAP was found operative mainly in the condensed-phase mechanism. (C) 2002 John Wiley Sons, Inc.