Cotton fabric finishing based on phosphate/clay mineral by direct-coating technique and its influence on the thermal stability of the fibers

Abstract

Clay minerals are naturally non-combustible materials with potential applications for protection against thermal degradation in textiles. However, their immobilization on the surface of the fabrics is a complicating factor depending on many variables. The application of clay minerals using the technique of finishing by direct-coating seems a viable alternative, which meets the environmental demand for less polluting, fast, simple, and cheap applications. Thus, in the present work, a study about the influence on the thermal stability of cotton fibers, from the textile fabric containing different formulations based on ammonium polyphosphate (APP) and sodium montmorillonite (Na-Mt) was evaluated. The additives were dispersed into a polymeric paste and applied unilaterally on fabric by direct-coating technique. The treated samples showed an improvement in thermal stability and heat release as a function of the Na-Mt/APP ratio loaded into the fabric. A reduction of the heat release rate (pHRR) around 51.6% and an increase of the carbonaceous residue at 800 °C was observed. The study of the thermal stability of the treated cotton fabric using the techniques of PCFC and TGA, with the aid of an experimental planning allowed the understanding of the interaction and synergy phenomena between the components of the formulation applied via direct-coating.