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The Metal oxide nanoparticles, used as fillers in polymer matrices have resulted in remarkable changes in the physio-chemical properties of the resulting polymer nanocomposites. The zinc oxide (ZnO), cobalt oxide (Co3O4) and magnesium oxide (MgO) nanoparticles were synthesized using solution combustion synthesis. Mechanical properties of the polymer nanocomposites prepared by solvent casting were examined by a nanoindentation technique and they are found to exhibit a notable decrease in the elastic modulus and hardness. The plastic deformation in the polymer nanocomposites occur at a lower indentation depth compared to the pristine PVA indicating that the nanocomposites are more ductile than the host polymer. [ABSTRACT FROM AUTHOR]

In the present work, pure polyvinyl alcohol (PVA) and PVA doped with sodium fluoride (NaF) polymer electrolyte films with different weight percent ratios were prepared by solution casting method. The effect of NaF concentration on the optical properties of (PVA-NaF) films has been investigated using UV-Vis Spectrophotometer in the wavelength range (200-800 nm). The optical constants like absorption spectra, transmission spectra, refractive index, extinction coefficient, real and imaginary parts of the dielectric constant and optical band gaps are investigated. It was found that the optical energy band gap is decreased upon the increase in NaF salt concentration which is contrary to the variation of conductance. The experimental results show that the optical constants showed clear changes with increasing the doping concentrations. [ABSTRACT FROM AUTHOR]

Solid polymer blend electrolyte films of PVA (Polyvinyl Alcohol) and PEG (Polyethylene Glycol) doped with NaF (Sodium Fluoride) are characterized by XRD and FTIR techniques. The X-ray diffraction (XRD) spectra shows a characteristic peak of PVA indicating its semi-crystalline nature. By the addition of NaF into the polymer blend matrix, the intensity of peak decreases gradually, suggesting a decrease in the degree of crystallinity of the samples. FTIR study confirmed the complexation and functional group occurred by the addition of NaF in the polymer blend. Dielectric and a.c. conductivity studies were carried out to the as prepared films at room temperature. Dielectric Constant (ε′) is maximum and found to decrease with increase in frequency and electrical conductivity of the complexed polymer blends increases by the addition of NaF. Literature reveals that these films found applications in energy storage devices. [ABSTRACT FROM AUTHOR]

Solid Polymer electrolyte films based on Poly (vinyl alcohol) (PVA) containing Sodium fluoride (NaF) and PEG (Polyethylene Glycol) as plasticizer are prepared by solution casting method and characterized by XRD and FTIR techniques. The X-ray diffraction (XRD) spectra shows a characteristic peak of PVA indicating its semi-crystalline nature. By the addition of NaF, PEG and NaF into the polymer blend matrix, the intensity of peak decreases gradually, suggesting a decrease in the degree of crystallinity of the samples. FTIR study confirmed the complexation and functional group occurred by the addition of NaF and plasticizer PEG in the polymer blend. Dielectric and a.c. conductivity studies were carried out to the as prepared films at room temperature. Dielectric Constant (ε′) is maximum and found to decrease with increase in frequency and electrical conductivity of the complexed polymer blends increases by the addition of NaF with PEG. Literature reveals that these films found applications in energy storage devices. [ABSTRACT FROM AUTHOR]

The nanofillers in the macromolecular matrix have displayed noteworthy changes in the structure and reactivity of the polymer nanocomposites. Novel functional materials usually consist of defects and are largely disordered. The intriguing properties of these materials are often attributed to defects. X-ray line profiles from powder diffraction reveal the quantitative information about size distribution and shape of diffracting domains which governs the contribution from small conventional X-ray diffraction (XRD) techniques to enumerate the microstructural information. In this study the MgO nanoparticles were prepared by solution combustion method and PVA/NaCl/MgO nanocomposite films were synthesized by the solvent cast method. Microstructural parameters viz crystal defects like stacking faults and twin faults, compositional inhomogeneity, crystallite size and lattice strain (g in %), were extracted using whole pattern fitting method. [ABSTRACT FROM AUTHOR]

Polymer electrolyte films of Poly (vinyl alcohol) (PVA) doped with Sodium fluoride (NaF) of different weight ratios (6, 8 and 10 wt %) were prepared by solution casting method. We observed that AC conductivity was found to increase with rise in temperature and frequency with slope S ranging from 0.7 to 0.9. The Correlated Barrier Hopping (CBH) model is used because the value of S is temperature dependent and its value decreases by increasing temperature. The dielectric constant has high values in the low frequency region; this is due to the existence of various types of polarization mechanisms. The X-ray diffraction (XRD) diagram of pure PVA shows a characteristic peak at 2θ=19.490 indicating its semi-crystalline nature. On the incorporation of NaF salt into the polymer, the intensity of peak decreases gradually, suggesting a decrease in the degree of crystallinity of the complex. The CBH model is used to calculate the polaron binding energy (WM), the Hoping distance (R), the minimum hoping distance (Rmin) and the activation energy (Ea) results are discussed. [ABSTRACT FROM AUTHOR]

Thermal effect in the form of micro wave energy on Jayadhar cotton fiber has been investigated. Microstructural parameters have been estimated using wide angle x-ray scattering (WAXS) data and line profile analysis program developed by us. Physical properties like tensile strength are correlated with X-ray results. We observe that the microwave radiation do affect significantly many parameters and we have suggested a multivariate analysis of these parameters to arrive at a significant result. [ABSTRACT FROM AUTHOR]