Smolder of Cellulosic Fabrics. III. The Control of Radical Driven Reactions

Abstract

The temperature programmed decomposition of cellulosic fabric was studied. Temperature Programmed Reaction (TPR) experiments performed in an inert atmosphere revealed that UV irradiation of #6 cotton duck fabric pro moted an increase in the degree of cellulose decomposition, while decreasing the onset temperature of decomposition. DSC-in-air experiments using these sam ples verified these observations. DSC spectra for non-irradiated samples revealed little difference in heat flows. Intramolecular redox reactions induced during UV irradiation formed hydroperoxide groups, generating relatively low heat flow. These results imply that the major role of incorporated oxygen was the facilitation of low heat cellu lose degradation and cleavage reactions. Potassium iodide introduced into the fabric resulted in lower cellulose degradation activity in an inert gas at tempera tures below 240°C. Reduction of the peroxide groups in the cellulose by iodide ions was assumed to cause this change. Monoethanolamine and nicotine were also applied to the cellulosic fabric, de creasing the rate of CO x formation. DSC spectra showed that low temperature heat-producing cleavage was suppressed. Nicotine and other components of ciga rette smoke were found to act as inhibitors of the onset of cellulosic smolder, thus preventing the smolder of cellulosic fabric.