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This paper presents the in‐situ chemical synthesis of silver nanoparticles (AgNPs) with glycerol embedded in poly(vinyl alcohol) (PVA) to synthesize (PVA/AgNPs) polymer nanocomposites with different volume percentages of AgNPs (2, 4, and 6) %v/v. X‐ray diffractometer shows the (200) plane of AgNPs, which appeared at 44.82° in PVA/(2, 4, and 6) %v/v AgNPs films. However, the (111), (220), and (311) planes at 2θ (37.55°, 65.08°, and 77.45°) respectively appeared in PVA with 6%v/v AgNPs only. Fourier transform infrared spectroscopy spectrum of AgNPs shows a COC peak at 1273 cm−1 which is attributed to the stronger affinity of AgNPs on the COC bonds in the PVA matrix. The scanning electron microscope confirmed that all nanoparticles are open‐spherical or near‐spherical in shape. Differential scanning calorimetry shows the decrease in glass transition and melting temperature of pure PVA from 64.62° and 185.54° to 53.09° and 182.35° after the incorporation of AgNPs. Thermogravimetric analysis shows the reduction of thermal stability of PVA/AgNPs films when compared to pure PVA. The electrical conductivity of PVA/AgNPs films increased with the addition of AgNPs. From Mechanical studies, the values of Young's modulus, yield strength, and ultimate tensile strength decreased with increasing AgNPs volume percentage. [ABSTRACT FROM AUTHOR]

Copper-ion conducting gel polymer electrolyte (GPE) systems based on polymer poly(vinyl alcohol) (PVA) and copper sulphate salt doped with glycerin as plasticizer have been synthesized by using solution casting technique. Differential scanning calorimetry (DSC) is used to examine the thermal effect of glycerin on a polymer electrolyte. With the addition of various quantities of glycerin, as a plasticizer in pure PVA and PVA + 20 wt% CuSO4 polymer electrolyte shows a decrease in the values of melting temperature, glass transition temperature and percentage of crystallinity. From TGA curves, it is observed that thermal degradation of the glycerin doped polymer electrolyte is shifted towards lower temperature when compared to pristine PVA and the weight loss of the polymer electrolyte increases with increase of glycerin concentration. From DTG analysis, the temperature of maximum decomposition for PVA is 283.4 °C and it is decreased by the addition of 20 wt% CuSO4 and upon increased concentration of the plasticizer from 1 to 3 mL of glycerin. For pure PVA and PVA + 20 wt% CuSO4, ε′ decreases with increasing glycerin concentration and is lowest at 3 mL glycerin concentration. The maximum ionic conductivity obtained was 9.39 × 10− 4 S/cm for PVA + 20 wt% CuSO4 + 3 mL glycerin gel polymer electrolyte. The above results suggested that, the optimum conducting sample is suitable as separator in rechargeable batteries. [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte films containing poly(vinyl alcohol) (PVA) and magnesium nitrate (Mg(NO 3) 2) were prepared by solution casting technique and characterized by using XRD, FTIR, DSC and AC impedance spectroscopic analysis. The amorphous nature of the polymer electrolyte films has been confirmed by XRD. The complex formation between PVA and Mg salt has been confirmed by FTIR. The glass transition temperature decreases with increasing the Mg salt concentration. The AC impedance studies are performed to evaluate the ionic conductivity of the polymer electrolyte films in the range of 303–383 K, and the temperature dependence seems to obey the Arrhenius behavior. Transport number measurements show that the charge transport is mainly due to ions. Electrochemical cell of configuration Mg/(PVA + M g(NO 3) 2) (70:30)/(I 2 + C + electrolyte) has been fabricated. The discharge characteristics of the cell were studied for a constant load of 100 kΩ. [ABSTRACT FROM AUTHOR]