Detection of Magnesium Oxide in the Ashes of a Burnt Cellulosic Fabric Treated by Magnesium Chloride Hexahydrate as a Flame-Retardant

Abstract

The authors investigated the effect of magnesium chloride hexahydrate [Mg Cl₂ · 6H₂O] as a nondurable finish on the flammability of 100% cotton fabric (woven construction, weighing 144 g/m². The laundered bone-dried, weighed fabrics were impregnated with various concentrations of the aqueous aforementioned salt solutions by means of squeeze rolls and drying in an oven at 110°C for 30 min. The specimens were then cooled in a desiccator, re-weighed with an analytical balance, and kept under standard conditions before the fulfillment of the vertical flame test. The optimum add-on values to impart flame-retardancy expressed in g anhydrous magnesium chloride hexahydrate per 100 g fabric were about 6.73% to 8.30%. The ashes of the treated specimens were subjected to X-ray diffraction analysis (XRD), and the result was compared with data for MgO powder. The existence of MgO was detected in the ashes. The results obtained for magnesium chloride hexahydrate are in favor of the “Gas Theory,” “Free Radical Theory,” and also “Dust or Wall Effect Theory.”

Keywords:

• dust or wall effect
• flame-retardancy
• flammability
• free radical theory
• gas theory
• magnesium chloride hexahydrate
• X-ray diffraction

Acknowledgments

The authors are grateful to Gilan University for financial assistance of this research project.