PANI-derived polymer/Al2O3 nanocomposites: synthesis, characterization, and electrochemical studies

This paper presents the physicochemical, conductive, and electrochemical properties of different polyaniline (PANI)-derived polymer/Al2O3 nanocomposites synthesized by chemical oxidation polymerization method carried out in two stages: first, activation of the surface of the Al2O3 nanoparticles by hydrochloric acid and second, polymerization of 2-chloroaniline (2ClANI), aniline (ANI), and the copolymer (2ClANI-ANI) in the presence of Al2O3 by using ammonium persulfate as oxidant in aqueous hydrochloric acid. XRD and TEM results reveal the growth of the polymers on Al2O3 nanoparticles and the formation of PANI-derived polymer/Al2O3 nanocomposites. FTIR and UV-Vis show a systematic shifting of the characteristic bands of the polymers with the presence of Al2O3 nanoparticles. Moreover, these nanoparticles enhance the thermal stability of the polymers, as found by thermogravimetric analysis (TGA). Although the incorporation of Al2O3 nanoparticles reduces the electric conductivity of the polymers, the resulting nanocomposites still keep high conductivities, ranging between 0.3 × 10−2 and 9.2 × 10−2 S cm−1. As a result, the polymer/Al2O3 nanocomposites exhibit a good voltammetric response. All these synergetic features of the nanocomposites are assigned to the effective interaction of the polymers and Al2O3 particles at nanoscale.This work was supported by the National Assessment and Planning Committee of the University Research (CNEPRU number E-03720130015), the Directorate General of Scientific Research and Technological Development (DGRSDT) of Algeria. The financial support from MINECO is also acknowledged (MAT2013-42007-P project)

Positional Isomeric Effects on the Physicochemical Properties of Polymeric Matrix and Polymer@TiO₂ Nanocomposites

This study investigates the influence of positional isomerism on the physicochemical characteristics of polymeric matrices by examining polyo-anisidine (POA) and polyp-anisidine (PPA) in conjunction with TiO2 nanoparticles. The synthesis of POA@TiO2 and PPA@TiO2 involved chemical oxidative polymerization. X-ray diffraction analysis revealed the anatase structure of TiO2 nanoparticles. Transmission electron microscopy confirmed the successful integration of TiO2 nanoparticles within the polymer matrix. Moreover, FTIR and UV–Vis spectroscopy confirmed the effective interaction between the nanoparticle and the polymer. TGA indicated that POA@TiO2 exhibited a lower weight loss than PPA@TiO2, suggesting an enhancement in thermal stability. Although the incorporation of TiO2 nanoparticles led to a reduction in the electrical conductivity of the pristine polymers (PPA and POA), the resultant nanocomposites retained high conductivities within the range of 0.08 to 0.34 S.cm−1. Furthermore, the POA-based polymer matrix displayed promising electrochemical properties. Significantly, the adherence of the POA layer to TiO2 nanoparticles suggests potential practical applications