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The manufacture of flexible devices is of immense interest due to their eco-friendliness, economic prospects and wide range of applications in biocompatible devices. Therefore, this paper reports the characterization and properties of chlorinated natural rubber (Cl-NR)/polyindole (PIN) blend with different contents of nickel oxide (NiO) nanoparticles. The formation of blend nanocomposites was analysed by FT-IR, UV spectroscopy, XRD, FE-SEM, DSC and TGA. The FT-IR and UV spectra proved the effective interfacial interaction between nanoparticles and the blend matrix, with a shift in UV peak intensity with the attachment of NiO at 433 cm−1. The XRD pattern revealed the regular arrangement of the blend matrix due to the presence of nanofiller, resulting in the semicrystalline structure of the composite system. The SEM micrographs revealed a homogeneous distribution of NiO in the blend matrix. The increased degradation temperature in the TGA demonstrated the enhanced thermal stability of the NiO-filled Cl-NR/PIN blend. DSC results showed that the glass transition temperature of the composite increased with NiO content in the blend matrix. The dielectric properties and AC electrical conductivity increased significantly with increasing temperatures, as well as with the addition of nanoparticles up to 5 mass % loading. The inclusion of NiO improved the tensile strength and hardness while reducing the elongation-at-break of nanocomposites. The blend nanocomposite with enhanced thermal stability, glass transition temperature, tensile strength, AC conductivity and dielectric properties enables them to be used in highly flexible electronic applications where traditional elastomeric materials fall short. [ABSTRACT FROM AUTHOR]

The nanohybrid consists of polyvinyl chloride (PVC) and polyvinylidene fluoride (PVDF) nanostructure network with BaZrO3 and BaTiO3 nanoparticles separately. The mass ratios of PVC-PVDF-BaZrO3/BaTiO3 were chosen to be 60:36:04. The structural morphology of nanohybrid was examined by using Raman spectroscopy and scanning electron microscopy (SEM). The Raman spectroscopy is enabled to explain strong interaction between the nanoparticles and polymer matrix. The PVC-PVDF- 4 mass% BaTiO3 nanohybrid shows high dielectric permittivity, breakdown strength and the energy density as compare to pure polymer matrix. DSC analysis of nanohybrid is attributed the good thermal stability due to crystallization effect in presence of nanoparticles. The findings of present work enable to design the energy storage devices. [ABSTRACT FROM AUTHOR]

Poly (vinylidene fluoride) (PVDF) and nanocomposite samples were prepared by the solution-grown method. The surface morphology of PVDF-ZnO nanocomposite was characterized by SEM (scanning electron microscopy). The dispersion of nanoparticle in PVDF matrix was clearly viewed by SEM spectra. The interaction between the nanoparticle and PVDF was studied by XRD (X-ray diffraction) and FTIR (Fourier transform infrared spectroscopy) spectra. The intensity of IR spectra decreases after the addition of KI (Potassium iodide) functionalized ZnO nanoparticle, which is evidence of atomic interaction. XRD spectra confirm the presence of crystalline and amorphous regions. The variation of dielectric properties including dielectric permittivity and dielectric loss were studied for different frequencies and temperature. Dielectric study showed that the incorporation of ZnO nanoparticle in PVDF matrix resulted the increase in dielectric permittivity due to increase in β phase content. The decrease in dielectric permittivity and dielectric loss with increase in frequency confirms the presence of dipoles or interfaces. Dielectric permittivity increases with temperature because the molecular chain segmental motions at room temperature, which are practically frozen. The differential scanning calorimetry (DSC) results show significant endothermic peaks of PVDF and PVDF nanocomposite corresponding to the glass transition temperature and melting temperature. [ABSTRACT FROM AUTHOR]

The results obtained from thermogravimetric (TG) analysis, X-ray diffraction analysis, optical characterization and dielectric measurements of the samples were investigated. In X-ray diffraction patterns, the presence of both BaCO3 and ZnO peaks showed that ZnO and BaCO3 nanocrystals were independently grown. Changes in the band peak position in the FTIR spectra showed that the chemical structure of Ba:Zn nanocomposites changed with the doping of graphene oxide. The optical band gap (Eg) of the samples was calculated as 3.18, 3.19, 3.2, 3.21 and 3.23 eV for BaZn, BaZn25, BaZn50, BaZn75 and BaZn100, respectively. It was determined that the dielectric constants and dielectric losses of the nanocomposites exhibited normal dielectric behavior, decreased with the frequency described in light of Maxwell–Wagner model and increased with increasing graphene oxide concentration. TG measurement showed that the mass loss in the sample decreased with increasing graphene oxide. [ABSTRACT FROM AUTHOR]

New poly(aryl ether ketone)s (PAEKs) with a low melting temperature (relative to PEEK) are of interest in order to simplify the manufacturing of high-performance polymers or composites. In this study, we propose to investigate the physical properties of a new PAEK from Victrex, namely PAEK LM. Combinations of thermal analyses were used as follows: standard and modulated temperature differential scanning calorimetry, dynamic mechanical analysis, dynamic dielectric analysis and guarded hot plate technique. We found that the global mechanical, dielectric and thermal properties are very similar to the PEEK reference. The glass transition temperature was observed in the same range than PEEK (∼ 150 °C) while the melting temperature Tm was measured at 307 °C for PAEK LM which is about 35 °C below the melting temperature of PEEK. The degree of crystallinity of PAEK LM was found to be 27% while for PEEK it is 38%, depending on the processing conditions. This work explored crystalline structure-property relationships to explain the behaviour of PAEK LM. [ABSTRACT FROM AUTHOR]

This study focused on the fabrication of poly(n-butyl methacrylate) (PBMA) nanocomposites with various concentrations of cerium-doped titanium dioxide (Ce-TiO2) nanoparticles via in situ polymerization technique. The structural characterization and the material properties of all the composites were analyzed by UV-visible, FTIR, XRD, SEM, DSC, TG, and tensile strength measurements. The UV-visible and FTIR studies confirmed the effective inclusion of Ce-TiO2 nanoparticles into the PBMA matrix. The change in amorphous morphology of PBMA to a crystalline structure was observed from the XRD pattern. The SEM morphology revealed the attachment of nanoparticles in the polymer matrix. The inclusion of Ce-TiO2 nanoparticles enhanced the glass transition temperature, and thermal stability of the PBMA matrix was revealed from DSC and TG, respectively. The tensile strength of PBMA was greatly enhanced by the addition of Ce-TiO2 nanoparticles. The AC conductivity, dielectric constant, and dielectric loss studies were also performed in the frequency range 102-106 Hz, and it was observed that addition of Ce-TiO2 nanoparticles greatly enhanced the electrical properties of PBMA. The change in dielectric constant with the addition of nanoparticles was correlated with a theoretical modeling study. This work also extended to study the role of Ce-TiO2 nanoparticles in the reinforcing mechanism of the nanocomposite by comparing the actual tensile strength of the composite with different theoretical modeling. The high dielectric constant and tensile strength of composite are beneficial in designing lightweight and highly efficient nanoelectronic materials based on the family of polybutyl acrylates. [ABSTRACT FROM AUTHOR]

Calcium copper titanate powders were synthesized by a soft chemistry route, aiming to establish a cost-effective solution method to obtain sintered ceramics with giant electric permittivity (ε′) and low dissipation factor (tanδ). Powders and sintered pellets were characterized by several techniques. The thermal decomposition behavior of the porous foam evidences that a hydroxycitrate was formed below 200 °C. Single cubic perovskite-type phase was obtained after calcination of the precursor powder at 700 °C for 5 h. Negligible mass loss occurs above 400 °C. During heating the precursor material, CuO is the first crystallized phase. A giant ε′ and low tanδ are obtained after sintering. The extension of the thermal window of ε′ is wider than those of powders prepared by other methods. [ABSTRACT FROM AUTHOR]

A new series of four different linear aliphatic ether linked aromatic bismaleimides (AEBMIs) were synthesized from the respective linear aliphatic ether-linked aromatic diamines and maleic anhydride. Further, the POSS-AEBMI nanocomposites were developed by Michael addition reaction of bismaleimide with varying mass percentages of octa(aminophenyl)silsesquioxane and were characterized by the fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Data from thermal studies revealed that the POSS-reinforced AEBMI nanocomposites possesses higher glass transition temperature ( Tg), thermal stability, limiting oxygen index, and lower dielectric constant when compare to that of neat AEBMI. X-ray diffraction and transmission electron microscopy analysis confirmed the molecular level dispersion of POSS in the AEBMI matrix. [ABSTRACT FROM AUTHOR]

Exfoliated graphite nanoplatelets (GNP)/epoxy resin nanocomposites were prepared and tested, varying the amount of the filler content. Systems' morphology was investigated by means of scanning electron microscopy, while their thermal response was examined via differential scanning calorimetry (DSC). Broadband dielectric spectroscopy and dynamic mechanical thermal analysis were employed in order to characterize the produced systems. Static mechanical tests were also conducted at ambient. Reinforced systems exhibit improved performance under mechanical and electrical excitation. In particular, storage modulus increases systematically with GNP content. DSC results imply that glass transition temperature is not affected by the presence of GNP. Flexural modulus and storage modulus, as determined by static and dynamic mechanical tests, respectively, increased with filler content. Dielectric permittivity increases also systematically with GNP content. Recorded relaxation processes arise from the glass to rubber transition of the polymer matrix (α-mode), re-orientation of polar side groups of the polymer chains (β-mode), and interfacial polarization because of the accumulation of charges at the systems' interface. Finally, the energy storing efficiency of the nanocomposites enhances with reinforcing phase in the examined frequency and temperature range. Optimum performance corresponds to the nanocomposite with maximum GNP loading. [ABSTRACT FROM AUTHOR]

Polycrystalline ceramic samples of BiSnTiO ( x = 0.0, 0.2, 0.4, 0.6, 0.8) have been synthesized by conventional solid-state reaction method. The effect of homovalent cation (titanium) substitution on the Sn-site on the structural, morphological, electrical and thermal properties of the pure BiSnO ceramics have been studied by X-ray diffraction (XRD) followed by scanning electron microscopic techniques, dc conductivity and modulated differential scanning calorimetry. The XRD analysis carried out by performing the Rietveld refinement using the space group Fd3m indicates that the increase of titanium contents do not lead to any secondary phase. The grain size distributions of all the samples were investigated by SEM. It was found that the grain sizes are strongly influenced by the addition of titanium to the system. The frequency and temperature dependent dielectric studies have been carried out. The dc conductivity measurement was carried out for all the compounds and the activation energies were calculated using the relation σ = σ0 exp(− E/ kT). The modulated differential scanning calorimetry has been used to investigate the effect of substitution on the specific heat, heat flow and other thermal parameters of the compounds. The results are discussed in detail. [ABSTRACT FROM AUTHOR]