Improvement of microwave absorption for PAni/HA/TiO₂ /Fe₃ O₄ nanocomposite after chemical treatment

Abstract

In order to obtain efficient microwave absorbers that possess high conductivity, dielectric and magnetic properties, hexanoic acid doped polyaniline (PAni) nanocomposites which contain different ratios of ferum (II) oxide (Fe3O4) and titanium dioxide (TiO2) nanoparticles were successfully prepared by in situ chemical polymerization through template free method. Chemical structure, conductivity, morphology, thermal stability, magnetic properties, and amorphous/crystalline behavior of PAni nanocomposites were characterized by Fourier transform infrared spectrometer (FTIR), four point probe, field emission scanning electron microscope (FESEM), thermal gravimetric analysis (TGA), vibrating samples magnetometer (VSM), and X‐ray diffractometer (XRD), respectively. From this study, conductivity was significantly improved from 8.48 × 10−4−1.23 × 10−2 S/cm for PAni nanocomposites without any chemical treatment (during addition of Fe3O4) to 3.58 × 10−2−4.77 × 10−2 S/cm for those with chemical treatment. PAni nanocomposites with chemical treatment show a narrow sharp reflection loss (RL) peak with high absorption (−48.9 dB) at lower frequency due to the limited individual Fe3O4 nanoparticles outside the nanorods/nanotubes as proved by the new proposed mechanism (Fig. ), while it shows a broad RL peak with poor absorption (−13 dB) at higher frequency for those without chemical treatment. The novelty of this research has been focused on PAni with chemical treatment which yield better microwave absorption property (99.999% absorption), combination of high conductivity (3.58 × 10−2−4.77 × 10−2 S/cm), high heterogeneity and moderate magnetization (Ms = 8.87–28.49 emu/g) compare to the PAni without chemical treatment. POLYM. COMPOS., 34:1186–1194, 2013. © 2013 Society of Plastics Engineers

Dual-functional natural-fiber reinforced composites by incorporating magnetite

“…In order to reduce or avoid the electromagnetic pollution, the development of EMI shielding material from fully sustainable and eco-friendly materials have become an urgent issue for researchers in the composite industry. Generally, the most commonly used method is to block the field with barriers made of conductive or magnetic materials, so that the energy of electromagnetic wave was reduced to avoid the interference to the working electronic components [16,17]. At the present time, abundant EMI shielding materials and technologies have been produced and designed to reduce the interferences caused by electromagnetic signs [15,[18][19][20][21][22][23][24].…”

Effect of Titanium Dioxide and Carbon Nanotubes on Polyaniline Nanocomposites for Heavy Metals Removal

“…The amorphous nature of PAni was observed in XRD diffraction pattern for pristine PAni. The crystallinity of the PAni nanocomposites improved with incorporation of TiO 2 , SWNT and MWNT . The peaks observed at 25.3–25.4° (101)and 56.0–56.1° (105) 2θ angles are attributed to TiO 2 .…”

Polybenzobisoxazoles-based nanocomposites with high microwave absorption performance and excellent thermal stability

“…Therefore, PANI composites can be used as superior microwave absorbers [18][19]. It was reported when Fe 3 O 4 was modified with PANI, the wave absorbing properties of the resulting composites were largely improved [20][21][22][23] [23]. However, due to the low solubility of PANI in most solvents and the poor compatibility with polymer matrices, PANI coated Fe 3 O 4 core-shell particles had limited application in the composites so far.…”