Production of Electroconductive, Superhydrphobic and Flame-Retardant Cotton Fibers via Pad-Dry-Cure Process using Silicone Rubber and Ammonium Polyphosphate

Abstract

Although pyrovatex has been widely utilized as commercial flame-retardant material, the discharge of poisonous formaldehyde is still a major concern. On the other side, fluorine-based materials have been successfully used to impart superhydrophobic textile surfaces, but they are highly expensive and extremely toxic. Based on these challenging concerns, we report a simple one-step method for the production of flame-retardant and water-repellent coating onto an electroconductive cotton-nickel (Cot-Ni) blend fabric. Firstly, the electroconductive cotton was prepared by weaving nickel strip twisted around cotton core yarns, which were then weaved with pure cotton yarns to introduce Cot-Ni blend fabric. Secondly a composite comprising ammonium polyphosphate (APP) and room-temperature vulcanized silicone rubber (RTV) was applied onto the electroconductive cotton fabrics via one-step pad-dry-cure technique. Results showed that the flame-retardant effect of cotton was enhanced due to the high binding of RTV with both APP and cotton fibers. Thus, different concentrations of APP were implemented in the composite to establish that only 100 g/L of APP with RTV presented an improved fire-retardancy. The surface of Cot-Ni fabric displayed different hierarchical morphologies relying on the concentration of APP. Moreover, RTV further enhanced the superhydrphobic nature of cotton surface. Importantly, the superhydrophobic activity was characterized by static water contact angle of the coated Cot-Ni blend. The CIE Lab colorimetric measurements of the coated Cot-Ni blend were also explored. The comfort characteristics of the coated Cot-Ni blend were assessed by measuring their air permeability and stiffness. Ultimately, these multifunctional cotton-nickel (Cot-Ni)/RTV-APP treated fabrics could be suitable for diverse applications, including firefighters’ wear, car seat mats, and grain storage containers.