Characterization of a selectively permeable coating to a woven fabric

Innovative chemical-protection materials for military and industrial applications are being developed that combine breathable barrier films with textile substrates. The use of block copolymers as the selectively permeable membrane relies on the phase-separation nature of the copolymer. The combination of polymer and fabric results in a material whose barrier and mechanical properties are influenced by the respective behavior of each constituent material. Production of such materials on an industrial scale, while a necessity for commercial success, can potentially influence the coated fabrics barrier and mechanical properties. Characterization of the coating microstructure and coated fabric mechanical properties are crucial for optimizing the combined performance of such materials.;This research characterizes the coating uniformity, phase morphology, and various mechanical behaviors of polymer-coated textiles fabricated by novel solvent combinations. All materials studied in this research consisted of a plain woven cotton/nylon blend fabric coated with a sulfonated poly(styrene- block-isobutylene-block-styrene) (SIBS) copolymer. Samples were supplied by EIC Labs with some being dip coated while others were coated on an industrial scale using a doctor blade setup. Scanning electron microscopy analysis was used for the assessment of the coating uniformity as well as the level of adhesion between the polymer coating and fabric substrate. Transmission electron microscopy was used to characterize the phase separation morphology of the SIBS copolymer coating. The mechanical behavior of the coated fabric was determined through tensile, shear, and friction tests and is compared to the bare fabric behavior. Results show that processing conditions affect both the formation of the coating microstructure as well as the coated fabrics mechanical properties. Additionally, the mechanical properties of the bare fabric are noticeably altered by the presence of the coating material.