Polyaniline-doped benzene sulfonic acid/epoxy resin composites: structural, morphological, thermal and dielectric behaviors

Abstract

Conducting polymer composites, which are simply physical mixtures of an insulating polymer matrix and intrinsically conducting polymers, are promising new materials for various applications such as antistatic coatings, shielding and electromagnetic absorbers. In this context, a novel conducting composite was successfully produced. It is based on epoxy resin and polyaniline (PANI) doped in benzene sulfonic acid, which was used as conducting filler. The effect of PANI loading levels on the structural, morphological, thermal, electrical and dielectric properties was explored using techniques, such as Raman, Fourier transform infrared and ultraviolet-visible-NIR spectroscopy, X-ray diffraction, atomic force microscopy, scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry. The electrical behavior and morphology of the synthesized PANI revealed disorder and defects. In addition, as the applied voltage is increased, the current through the sample increases rapidly. The conductivity and dielectric properties were also investigated at room temperature in the frequency range of 1 MHz-1 GHz. The dielectric constant was shown to increase with increased loading at low frequencies and then decreases rapidly, reaching a constant value at higher frequencies. In addition, the AC conductivity of the prepared composites increases with the addition of PANI and is higher at high frequencies. Furthermore, the stability of the composites was found to be influenced by increasing the amount of PANI filler in the matrix.

Structural and Morphological Characteristics of Polyaniline Synthesized in Pilot Scale

“…3) that is assigned to vibration of a delocalized polaron structure (Belaabed et al 2010). The band at 1502 cm −1 (arrow in Fig.…”

Characterization and Evaluation of Silver-Nanoparticle-Incorporated in Composite Graphite Aiming at their Application in Biosensors

“…Chauhan et al (2011), studying the thermal behavior of emeraldine base PANI, reported two significant different events: one in the range of 25°C to 60°C, credited to the evaporation of adsorbed water, and a second between 90°C to 115°C due possibly to cross-linking reactions between nearby quinoidal rings in the structure of the polymer. Belaabed et al (2010) found that the PANI-doped BSA is thermally stable up to 600 ºC working in a nitrogen flow (20 mL/min) and a heating rate of 5 ºC/min, reporting that only 40% of weight loss was observed. Three significant events of weight loss were verified: the first in the range of 30 to 170 ºC, caused by the loss of absorbed water and oligomers.…”

Curing kinetics, thermomechanical and microwave behaviors of PANI-doped BSA/epoxy resin composites

“…These observations are in agreement with the thermogram obtained by thermogravimetric analysis (Figure 2). 16 The evaporation and degradation of BSA and the oxidation process of the PANI structure and its composites occurred between 170 and 390 1C. 7,18,19 To avoid deprotonation of the conducting PANI and maintain the conductivity of composites after the curing process, it was imperative to add a catalyst.…”

“…PANI-doped BSA with an [oxidant]/[aniline] molar ratio of B1.15 was prepared at À17 1C. 16 The product exhibited an electrical conductivity of 8-10 S m À1 as a pressed pellet. To ensure adequate dispersion, the PANI was dispersed in tetrahydrofuran for 3 h at room temperature using an ultrasonic bath, followed by magnetic stirring to improve the dispersion's quality.…”

“…The aim of this study was to build on previous work 16 in which composites of PANI/ER were prepared and cured using anhydride. The PANI-doped benzene sulfonic acid (BSA) was used as conducting filler.…”