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Colossal magnetoresistance materials have demonstrated large changes in resistance in the presence of magnetic fields. In the current work, a group of such materials, with the compositional formula La0.67Ba0.33MnO3 and 10% Fe, Co, Ni, Zn doped La0.67Ba0.33MnO3 have been prepared by conventional solid-state method. Structural analysis has been carried out by X-Ray diffraction method followed by Rietveld analysis. Magnetic transition between ferromagnetism to paramagnetism has been observed from the magnetic characterizations. Parameters such as Curie temperature (θP) and effective magnetic moment (µeff) are obtained from susceptibility analysis subject to Curie–Weiss law. Furthermore, magnetocaloric nature of the samples is examined from the M-H isotherms. Using Maxwell's relations, isothermal entropy change, ∆Smax are determined to check whether the prepared samples can be used for magnetic refrigeration around the room temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low temperature VRH conduction mechanism of Cd0.8Zn02S: Na samples were estimated. [•] Dielectric constant values were calculated. [•] Relaxation time values were computed. [ABSTRACT FROM AUTHOR]

This article describes a study on thermal behavior of poly(vinylidene fluoride-chlorotrifluoroetheylene) [poly(VDF-CTFE)] copolymers as polymeric binders of specific interest for high energy materials (HEMs) composites by thermal analytical techniques. The non-isothermal thermogravimetry (TG) for poly (VDF-CTFE) copolymers was recorded in air and N2 atmospheres. The results of TG thermograms show that poly(VDF-CTFE) copolymers get degrade at lower temperature when in air than in N2 atmosphere. In the derivative curve, there was single maximum degradation peak ( Tmax) indicating one-stage degradation of poly(VDF-CTFE) copolymers for all the samples. The other thermal properties such as glass transition temperature ( T g) and degradation temperature ( T d) for poly(VDF-CTFE) copolymers were measured by employing differential scanning calorimeter (DSC) technique. The kinetic parameters related to thermal degradation of poly(VDF-CTFE) copolymers were investigated through non-isothermal Kissinger kinetic method using DSC method. The activation energies for thermal degradation of poly(VDF-CTFE) copolymers were found in a range of 218-278 kJ/mol. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Nanocomposite particles of poly(chlorotrifluoroethylene- co-ethylvinyl ether) [poly(CTFE- co-EVE)]/poly(styrene acrylate) (PSA)/SiO2 were prepared with poly(CTFE- co-EVE)/PSA [CS(FS); core-shell (CS) fluoro surfactant (FS)] and hydrophilic SiO2 nanoparticles by a solution mixing method. This method yielded a homogeneous dispersion of hydrophilic SiO2 nanoparticles in the CS(FS) matrix. The nanocomposite particle composition was confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis. A slight improvement in the thermal stability was observed and the glass-transition temperature of the nanocomposite particles increased compared with the CS(FS) matrix. A remarkable enhancement was observed in the mechanical properties with an increase in the tensile strength from 1.1 to 6.2 MPa and with an increase in the elongation at break from 209.6 to 350.1% for the films with 15 wt % SiO2. The presence of a wettable PSA shell on the fluorocore made interaction possible with SiO2; this made it more hygroscopic with a decent water uptake capacity and an enhanced water contact angle. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012 [ABSTRACT FROM AUTHOR]

Colossal magnetoresistance materials have demonstrated large changes in resistance in the presence of magnetic fields. In the current work, a group of such materials, with the compositional formula La0.67Ba0.33MnO3 and 10% Fe, Co, Ni, Zn doped La0.67Ba0.33MnO3 have been prepared by conventional solid-state method. Structural analysis has been carried out by X-Ray diffraction method followed by Rietveld analysis. Magnetic transition between ferromagnetism to paramagnetism has been observed from the magnetic characterizations. Parameters such as Curie temperature (θP) and effective magnetic moment (µeff) are obtained from susceptibility analysis subject to Curie–Weiss law. Furthermore, magnetocaloric nature of the samples is examined from the M-H isotherms. Using Maxwell's relations, isothermal entropy change, ∆Smax are determined to check whether the prepared samples can be used for magnetic refrigeration around the room temperature. [ABSTRACT FROM AUTHOR]