Development of One-Step Water-Repellent and Flame-Retardant Finishes for Cotton

Pyrovatex is a well-known commercial flame-retardant which is commonly applied for cotton fibers. Unfortunately, Pyrovatex has the concern of discharging toxic formaldehyde, and additionally it necessitates formaldehyde-based cross-linking agents to enhance the flame retardant character and durability. Thus, formaldehyde level is considerably increased in the treated cotton fabrics. Herein, we develop a simple approach toward superhydrophobic and flame-retardant coating for cotton fabrics. We apply one-bath pad-dry-cure technique in absence of formaldehyde which is usually applied as a cross-linker for the application and fixation of the Pyrovatex flame-retardant. Room temperature vulcanized (RTV) silicone was employed as a formaldehyde free cross-linking agent which allowed using Pyrovatex at lower concentration compared to commercial cross-linkers. The flame retardancy of the fabric was improved as a result of the higher bonding of Pyrovatex with both cotton fibers and RTV which in turn was bonded to cotton fibers too. Only 150 g/L of Pyrovatex with RTV silicone introduced much better flame retardant efficiency than applying 450-500 g/L of Pyrovatex ACS alone. Furthermore, RTV silicone further improved the water-repellent effect on the fabric surface. Washing properties of the treated cotton fabrics proved durability. The surface morphology and comfort properties of the treated cotton was explored.