Smolder of Cellulosic Fabrics IV. Participation of Dye and Bleach Residues

Abstract

The oxidative decomposition of a green-and-white checkered cel lulosic fabric, designated as FOR-1, comprised of four different yarns, was stud ied using TPR/GC and DSC techniques. Containing different alkali metal ion (AM +) and dye concentrations, these four yarns experienced directionally selec tive smolder behavior during cigarette ignition tests. Measurements were per formed on the integrated fabric and on each of the four yarns. A model explaining the anisotropic smolder and high-temperature behavior of this fabric was developed. The decomposition of a heavily bleached, cellulosic sailcloth was also studied. The results showed an increase in the fabric degradation/cleavage rate com pared to unbleached #6 cotton duck. The DSC spectra of the sailcloth, however, did not significantly differ from that of the washed cotton duck. Similar thermochemical behavior was observed in the blue-dyed denim fabric contain ing 1500 ppm potassium; the low-temperature DSC behavior of this denim was also found to be similar to that of undyed, nicotine-treated cotton duck studied in Reference [4]. These results support a model comprising the mechanisms of smolder and combustion of colored cellulosic fabrics.