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In the present study, mixed-metal ceramic Fe0.01Al0.5La.0.01Zn0.98O particles and their composites with polyaniline (PANI) were prepared via sol-gel and in situ free-radical polymerization techniques, respectively. Particles and composite formation was confirmed by FT-IR spectroscopy. SEM studies showed the Fe0.01Al0.5La.0.01Zn0.98O particle's homogeneous dispersion in the polymer matrix. Ceramic particles were found to be in microdimensions. XRD analysis confirmed crystallite size in the range from 22 to 28 nm. Extensive rheological characterization was performed to check the durability of the materials for possible applications. Flow-curve tests suggested that the prepared materials are non-Newtonian (shear thinning) in nature. Increasing temperature have no appreciable effect on the viscosity which confirmed the mechanical stability of the materials. Based on frequency sweep test findings, the mechanical rigidity of the polymer has been enhanced (G′ = 2 × 102−5.22 × 103 Pa) by the introduction of ceramic particles. Conversely, creep compliance has been decreased considerably. [ABSTRACT FROM AUTHOR]

Bio-plasticizer based polyaniline (PANI)/lithium perchlorate (LiClO) composites were synthesized by the facile in situ method. The composites were characterized using the Fourier transform infrared spectroscopy (FT-IR) to identify the chemical interactions. A band appeared at 1502 cm due to the presence of the -HCO- group and CH scissor mode vibration for the PAL15% composite. This considerable change in the morphology of LiClO homogeneous dispersion in a PANI matrix was investigated by scanning electron microscopy (SEM). The UV-Visible absorption (UV-Vis) showed 300-400 nm attributed to the π- π* transition and exhibited a red shift from 535 nm to 617 nm in the visible region, indicating a decrease in band gap. The variations in dielectric constant with the addition of lithium perchlorate (LiClO) at different temperatures and in the frequency range of 20 Hz-1 MHz were assessed through impedance analysis. The temperature dependent electrical conductivity increased with increasing temperature as well as dopant concentration. High conductivity of 1.41 × 10 S/cm corresponding to activation energy of 0.02 eV and 2.95 eV optical band gap for 15 wt.% of LiClO concentration was observed. The cyclic voltammetry measurement revealed a typical rectangular shape of the integral area, suggesting that the composite has strong electrochemical strength and is a possible candidate for electrochemical super capacitor and solar cell applications. [ABSTRACT FROM AUTHOR]

A multi-hierarchical porous polyaniline (PANI) composite which could be used in good performance pressure sensor and adjustable sensitivity gas sensor has been fabricated by a facile in situ polymerization. Commercial grade sponge was utilized as a template scaffold to deposit PANI via in situ polymerization. With abundant interconnected pores throughout the whole structure, the sponge provided sufficient surface for the growth of PANI nanobranches. The flexible porous structure helped the composite to show high performance in pressure detection with fast response and favorable recoverability and gas detection with adjustable sensitivity. The sensing mechanism of the PANI/sponge-based flexible sensor has also been discussed. The results indicate that this work provides a feasible approach to fabricate efficient sensors with advantages of low cost, facile preparation, and easy signal collection. [ABSTRACT FROM AUTHOR]