• P Maji

      Articles written in Bulletin of Materials Science

    • Effect of Zn(NO3)2 filler on the dielectric permittivity and electrical modulus of PMMA

      P Maji P P Pande R B Choudhary

      More Details Abstract Fulltext PDF

      Composite films consisting of polymethyl methacrylate (PMMA) and Zn(NO3)2 were developed in the laboratory through the sol casting technique. These films were characterized using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The morphological analysis was carried out by scanning electron microscopy (SEM). These analyses revealed the homogeneous and semi-crystalline behaviour of the films. The dielectric response measurement was conducted in the frequency range from 100 Hz to 5 MHz. The real and imaginary part of the dielectric permittivity decreased with the increase in frequency but increased with temperature. The electrical conductivity measurement showed a plateau-like behaviour in the low-frequency region and dispersion in the high-frequency region. The frequency-dependent electrical modulus obeyed Arrhenius law, and it showed an increase in the dipolar interaction with the temperature due to thermal activation. The activation energy of the film specimen was estimated to be about 0.448 eV. Thus the polymeric composite PMMA–Zn(NO3)2 is one of the appropriate candidate for numerous technical applications such as supercapacitors, high-speed computers and gate dielectric material for organic FETs.

    • CoCl2 reinforced polymeric nanocomposites of conjugated polymer (polyaniline) and its conductive properties

      M Majhi R B Choudhary P Maji

      More Details Abstract Fulltext PDF

      Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline using ammonium persulphate as an oxidant in acidic aqueous medium. Cobalt chloride hexahydrate (CoCl2⋅6H2O)-doped PANI composite was synthesized by in-situ oxidative polymerization process by using various concentrations of CoCl2. Its chemical, structural and morphological properties were examined by X-ray diffraction, energydispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and field-emission scanning electron microscopy techniques. These results confirmed the successful formation of PANI and CoCl2-doped PANI nanocomposites. The morphology of CoCl2-doped PANI nanocomposite was found to be spherical in nature. The dielectric properties were examined using LCR-HITESTER in the frequency range 50 Hz–5 MHz. The optical properties were examined by UV–visible spectroscopic techniques in the wavelength range of 200–800 nm. The high dielectric properties and alternating current conductivity of the composite was studied in the temperature range 313–373 K. It was found that the synthesized polymeric nanocomposite owned fairly suitable dielectric and optical properties for its application in actuators, conductive paints and for many other purposes.

  • Bulletin of Materials Science | News

    • Dr Shanti Swarup Bhatnagar for Science and Technology

      Posted on October 12, 2020

      Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
      Chemical Sciences 2020

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2021-2022 Indian Academy of Sciences, Bengaluru.