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ABSTRACT In this study, acrylic-based conductive polymeric composite thin films were prepared by in situ chemical polymerization of pyrrole (Py) in the case of ammonium persulfate (APS) and iron(III) chloride (FeCl3). Composite thin films were produced by the solution casting method. The effect of polypyrrole (PPy) content and the type of oxidant on the morphological and dielectric properties were investigated. Temperature- and frequency-dependent dielectric properties were also studied in a frequency domain starting from 0.01 Hz to 10 MHz and in a temperature domain from 35 to 195°C. The results revealed that the dielectric constant and dielectric loss increased, whereas temperature and the highest dielectric values were obtained in the case of APS. The density of interconnected pores enwrapped with PPy under the surface improved the electrical/dielectric properties of the composite thin films. [ABSTRACT FROM AUTHOR]

Chemical oxidative polymerization of N-Methyl Pyrrole (NMPy) by cerium(IV) on Poly(Acrylonitrile-co-Vinyl Acetate) matrix in N,N-dimethylformamide (DMF) was performed. Electrospinning technique was used for the preparation of P(AN-co-VAc) solutions with uniformly distributed Poly(N-Methyl Pyrrole) (PNMPy) nanoparticles. In the presence of PNMPy, a new absorption band appeared at 1312 cm-1 which corresponds to CH in plane vibration peak. The dielectric properties of nanofiber composites were evaluated on the basis of the complex permittivity. The SEM and AFM images of composite nanofibers showed that the PNMPy nanoparticles with the dimensions of 20-40 nm were distributed homogeneously. [ABSTRACT FROM AUTHOR]

Abstract: Oxidative polymerization of acrylonitrile (AN) initiated by Ce(IV)–oxalic acid redox system in the aqueous medium was performed and polyacrylonitrile (PAN)/polypyrrole (PPy) composite thin films were prepared by polymerization of pyrrole on polyacrylonitrile matrix. Effect of concentration of pyrrole derivatives on the resulting polymeric film properties was investigated. The influence of the pyrrole derivative type and content on the dielectric permittivity, dielectric loss and electrical properties of the composite films were analyzed in the frequency range from 0.05Hz to 10MHz. For a selected concentration of 200μl of composite films at 107 Hz, the conductivity was found to be in the following order: PAN–PPy