The role of water in protective fabrics is critical to comfort and material performance. Excessive perspiration in clothing causes discomfort, and bound water can adversely affect the ability of carbon to adsorb chemicals. Yet the presence of water can also improve the moisture vapor transport of protective polymer films, and is essential for the hydrolytic destruction of nerve agents. Reported here are the findings of wicking and drying experiments conducted on various hydrophilic and hydrophobic cover fabrics that demonstrate the influence of wetting on permeation through fabrics. The influence of water content on reactive polymers capable of degrading nerve agent simulant is also discussed, and the importance of a novel “delivery system” for water to the reactive components through the use of a wicking fabric is introduced. 1. Introduction Current chemical protective fabrics rely on layers of activated carbon to adsorb chemical agent vapors. A tightly woven outer hydrophobic and oleophobic shell fabric provides liquid protection and aerosol particle protection. Another approach is to base protection on a semipermeable or reactive polymer membrane layer, which is permeable to water vapor, but which is also a barrier to chemical agents. The polymer membrane is usually laminated between an outer shell fabric and an inner fabric layer in contact with the skin. The outer fabric layer is treated to be hydrophobic and oleophobic. This allows water (rain), oils, and chemical agents to roll off of the fabric surface. However, the inner layer of these fabrics can be designed to pick up liquid sweat from the skin’s surface. The liquid wicking characteristics of this inner laminated “comfort layer” fabric can affect the perceived comfort of the garment and the total amount of sweat vapor capable of being transmitted through the laminated fabric and membrane structure. The research gap motivating the work presented in this study is the need to more fully understand how water amount and location affect reactive compounds present in fabrics and polymer membranes that are designed to hydrolytically decompose chemicals that are analogs for nerve agents. One such compound is the polymeric supernucleophilic pyridine catalyst called poly(butadiene-co-pyrrolidinopyridine) (polyBPP) [1–3], which functions to completely degrade the nerve agent surrogates, including the compound, diisopropyl fluorophosphate (DFP). Water interactions are involved in the degradation kinetics of DFP and require that there must be a sufficient amount of water and complete contact between the
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