Next Generation of Electrospun Textiles for Chemical and Biological Protection and Air Filtration

摘要

Protective clothing systems in current use are primarily based upon either full barrier protection through blocking contaminant permeation, or on air-permeable adsorptive protective overgarments in which all the toxins are adsorbed on contact. The adsorptive protective multilayer fabric systems are bulky and possess low moisture vapor permeability. These challenges motivate the development of a new generation of protective clothing system that is lightweight, breathable, and capable of selectively decomposing toxic agents on the fabric surfaces. Electrospun fabrics are remarkably breathable and lightweight; their high specific surface area can be used to functionalize the material by the attachment of functional compounds. In this dissertation, we aimed at developing electrospun fiber-based chemical and/or biological detoxifying protective fabrics containing a-nucleophilic oxime moieties that are capable of hydrolytically decomposing toxic organophosphate (OP) chemical nerve agents and pesticides, and/or biocides acting against bacterial contaminants. Oxime-functionalized electrospun fiber mats were obtained via electrospinning of a polymer blend containing reactive polyacrylamidoxime (PAAO) and parent polyacrylonitrile (PAN). The function of PAAO/PAN fiber mats was evaluated by the hydrolysis of p-nitrophenyl acetate (PNPA), mimicking toxic OP nerve agents and pesticides. The presence of PAAO in the reactive fiber mats significantly accelerated the hydrolysis of PNPA compared to its spontaneous hydrolysis. The effect of the fiber size on reaction rate indicated that intra-fiber diffusional resistances may limit the accessibility of the reactive oxime sites inside the fibers with the oxime-assisted hydrolysis occurring primarily on the fiber surfaces.