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Electrically conducting composite hydrogels of poly(acrylic acid-co-acrylamide) and polyaniline were prepared by a simple two-step synthesis process using an aqueous polymerization technique at room temperature and interfacial polymerization of aniline at a water/organic-solvent interface. The structures of the hydrogels so prepared were confirmed using Fourier transform infrared, UV-vis, X-ray diffraction, and scanning electron microscopy methods. The tensile strengths of the hydrogels were determined using a standard method (universal testing machine),

Poly(3-phenyl azomethine ethylthiophene) (PPAET) and poly(3-phenyl azomethine butylthiophene) (PPABT) have been synthesized by the oxidative coupling method using FeCl 3 as the oxidant. The polymers were thoroughly characterized using Fourier-transform infrared (FTIR) spectroscopy, 1 H nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis. The concomitant thermal, optical, and electrochemical properties of the polymers revealed that they possess excellent potential as photovoltaic materials. The electrochemical bandgaps of PPAET and PPABT are calculated to be 2.19 eV and 2.14 eV, respectively. The absorption spectra showed broad absorption over the wavelength range of 350 nm to 590 nm with a maximum absorption peak at 407 nm and 415 nm (k max ), respectively, for PPAET and PPABT. Polymer photovoltaic cells based on blends of polymers and TiO 2 nanoparticles have been fabricated, and the power conversion efficiencies (PCE) of the photovoltaic cells were measured to be 0.102% and 0.125%, respectively, for PPAET and PPABT.

ABSTRACT:Reported herein is a green route for the synthesis of macroporous polystyrene particles by suspension polymerization in water in sc-CO 2 medium using polyvinyl alcohol (PVA) as stabilizer, divinylbenzene (DVB) as cross-linker, and azobisisobutyronitrile (AIBN) as initiator. The solvent properties of sc-CO 2 are adjusted in such a way that it acts as a pressure-adjustable porogen. All the reactions were carried out at pressures of 70-320 bar and a temperature of 75• C with an agitation speed of 700 rpm. With an increase in pressure (>70 bar), the diameter of the particles increases (8-22 μm), and the surface area of the particles also increases. Similarly, the pore diameter of

Polyaniline/graphite (PA/G) composites were prepared by the incorporation of graphite in various proportions (0.2, 0.5, and 1.0%) into polyaniline (PA) through the in situ polymerization of aniline. The polymer composites were characterized by Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, a four-probe method, current-voltage characteristics, and cyclic voltammetry (CV). FTIR and UV-vis spectroscopy revealed interaction between graphite and the imine groups of PA. The polymer composites showed a crystalline nature with a hexagonal primitive structure.The uniform distribution of graphite particles was observed within the polymer matrix. The composites were found to possess good thermal stability up to 573 K. The conductivity of the composites was in the range 4.53-238.08 S/cm, and the conductivity varied with temperature. The band gap of the composites was found in the range 1.2-1.6 eV. The PA/G composites also displayed a reversible electrochemical response, as revealed by the CV study.