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Based on the research work of traditional electromagnetic shielding fabrics and frequency selective surfaces, the novel high-pass woven fabrics were proposed. Two different unit cell models were built and compared, and a series of design samples were further simulated based on the models. Through contrastive analysis and discussion of the simulated results, the validity of model 1 was verified and the influence rules of various parameters were explored. Compared with model 1, model 2 was more precise containing the textile information, like yarn crimp, fabric porosity and thickness, but model 1 could substitute model 2 to predict the transmission characteristics to some extent. The ratio of conductive and dielectric yarns affected the high-pass characteristics greatly, and different from two-dimensional high-pass woven fabrics, one-dimensional high-pass woven fabrics showed distinct polarization selective characteristics. Yarn electromagnetic parameters and fabric parameters could also exert an effect on the S21 curves in different degrees, which could help designers choose materials and determine the fabric parameters effectively. The modelling and simulation work could provide guidance to the development of actual high-pass woven fabrics.

Cellulose acetate was dissolved in trifluoroacetic acid and electrospun onto polypropylene non-woven material. An upstream layer of polypropylene non-woven material was added to form a three-layered polypropylene/cellulose acetate/polypropylene filter. The thickness of the electrospun cellulose acetate layer was varied by changing the electrospinning time. The fabricated filter was then characterized. Cellulose acetate nanofibers were also electrospun onto an aluminum foil collector with the aim of studying the changes in fiber properties when they are electrospun onto the polypropylene non-woven material. The results obtained in this research work indicated that the layer of nanofibers electrospun onto polypropylene non-woven material increased the filtration efficiency of polypropylene non-woven material from 50.23% to 91.29%, but the quality factor reduced by 29.1%. When the cellulose acetate deposition time was increased from 3 h to 6 h, the filtration efficiency further increased to 98.26% and the quality factor increased by 0.6%. A comparison between cellulose acetate nanofibers electrospun using an aluminum foil as the collector and those electrospun directly onto the polypropylene non-woven material indicated that cellulose acetate fibers electrospun onto polypropylene non-woven material had poorer fiber quality properties.

In this study, both air-oxygen-helium and air-helium atmospheric pressure plasma treatments were employed to desize PVA on a rayon (viscose) fabric. Both the plasma treatments were able to remove some of the PVA on the rayon fabric and increase PVA solubility in cold water, resulting in a higher weight loss in cold washing. The effect of the atmospheric pressure plasmas became greater as the treatment time increased. Plasma treatment followed by one cold and one hot washing had the same effect as the conventional chemical treatments followed by two cycles of cold and hot washing. The atmospheric plasma treatment did not have negative effect on rayon fabric tensile strength.