Fabrication of Laminated Electrospun Fire˗Resistant Phosphorylated Poly(Vinylalcohol) Membrane for Enhanced Firefighter Safety

Abstract The current study focuses on the creation of breathable and fire˗retardant fibrous membranes using phosphorylated poly(vinylalcohol) (PPVA) via the electrospinning method, with a specific interest in their application for structural firefighter clothing. Poly(vinylalcohol) (PVA) was phosphorylated to enhance its inherent flame resistance. Optimization of reaction conditions, including time and temperature, was conducted to achieve a solution suitable for electrospinning. The flame resistance of PPVA was confirmed through vertical flammability tests, with thermogravimetric analysis indicating a significant increase in carbonaceous char formation during PPVA decomposition compared to unmodified PVA. The limiting oxygen index also exhibited a notable increase from PVA to PPVA. Furthermore, the study established optimal operating conditions for producing uniform fibers, considering parameters such as polymer concentration, feed rate, tip to collector distance, and applied potential difference. The PPVA membrane demonstrated superior water vapor transmission rates compared to PVA, indicating enhanced breathability. The entire fabrication process utilized an environmentally friendly water‐based solvent. Additionally, a moisture‐cum‐thermal barrier layer (MCTB) was developed by laminating the PPVA fibrous membranes with microporous polytetrafluoroethylene and further with needle punch‐spunlaced OPAN fabric. Experimental assessments of the MCTB layer revealed satisfactory breathability and thermal performance, surpassing the standard requirements of 35 cal/cm 2 for structural firefighting configuration.