No abstract

Conductive polymers with their medium level of conductivity are synthetic materials that can be used as electromagnetic wave absorber. In this work, the effect of aging and washing on the surface resistivity and also the influence of efficient doping and redoping procedure on the dielectric properties and electromagnetic radiation shielding of uniformly polyaniline coated polyester fabric are investigated in the X-band frequency range. They can affect the shielding effectiveness by changing the surface resistivity and dielectric permittivity. It is found that lightweight, flexible, and thin polyaniline-coated polyester fabric sample prepared in 1:1:7 monomer:oxidant:dopant molar ratio and redoped with concentrated HCl vapor shows the highest transmission loss (53–43%) in 8.2–12.4 GHz. Compared to single layer, double and triple layer samples attenuated 71–61% and 83–77% of incident wave, respectively. Absorption was the dominant shielding mechanism. It is also demonstrated that the increment of surface resistivity due to washing of samples is compensated by the redoping process.

Conducting polyaniline-coated polyester textiles have attracted much attention due to their wide range of surface resistivity. The surface resistivity depends strongly on the polymerization condition. In this work, polyaniline coated on textile by in situ chemical polymerization method. The influence of substrate modification, synthesis condition, and especially redoping procedure on the surface resistivity of polyaniline-coated textile was investigated and an optimum condition specified. The obtained results indicate that polymerization in an ice-water bath and in a monomer:oxidant:HCl molar ratio equal to 1:1:7 for about 4-6 h decreases the surface resistivity significantly. Furthermore, the experimental results show that etching the surface of textile and redoping procedure with concentrated HCl vapor can decrease the surface resistivity, in a short time.

No abstract

No abstract