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Flexible nylon 11/CaCu 3 Ti 4 O 12 (CCTO) nanocomposite films (thickness ∼100 μm) with varying CCTO nanoceramics (0 to 30 wt%) were fabricated by solution casting method followed by vacuum drying. The nanocomposites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy, and impedance analyzer to study their structural and dielectric properties. XRD analysis revealed the presence of γ-phase of nylon 11 both in as-cast film as well as in the composites. SEM micrographs indicated that the CCTO nanocrystals were distributed evenly throughout the nanocomposite films with less agglomeration. The room temperature dielectric permittivity was 168 at 50 Hz when the CCTO content increased to 30 wt% in the polymer and this was increased to 1007 at 423 K. Frequency independent dielectric behavior was observed for the frequency range of 100 kHz–10 MHz. Temperature coefficient of permittivity showed that the permittivity of the nanocomposites is highly temperature dependent. [ABSTRACT FROM AUTHOR]

The dielectric material employed in this effort is a proprietary nanocomposite material, MU100. The material was initially developed to shrink high frequency high voltage dielectric loaded antennas; however, due to its unique material characteristics, the nanocomposite has shown promise in development of high voltage capacitors. Previous work has shown small-scale samples of the high permittivity nanocomposite material to have an average dielectric strength of 220 kV/cm with peak breakdown fields in excess of 328 kV/cm. When scaling up to realize application specific voltages, failure modes become more pronounced due to volume effects of the nanocomposite and field enhancement factors at the electrode dielectric interfaces. This work describes how the material was increased in volume from small samples up to compact capacitor prototypes capable of repeatable performance at 250 kV to in excess of 500 kV with lifetimes greater than 104 shots. [ABSTRACT FROM AUTHOR]

In this paper, a systematical investigation on a novel, facile, and inexpensive single-step chemical route has been used for the preparation of highly conducting polyaniline/nickel sulfide (PANI/NiS) magnetic nanocomposite films at room temperature. First, the nickel sulfide nanoparticles with particle size in the range of 45–70 nm were synthesized using nickel chloride as a precursor, and then PANI nanocomposite films were prepared by dispersing different weight percentages of NiS (0%–5%) in the monomer using nebulizing technique with nitrogen gas as a driving force for monomer atomization. These novel grown films were then characterized for their microstructure, magnetic, and conducting properties by X-ray diffraction analysis, vibrating sample magnetometer, scanning electron microscopy, and two-point probe method. This technique has successfully resulted in good quality, highly conducting, ferromagnetic, uniform, well adherent, and porous nanostructure films. [ABSTRACT FROM PUBLISHER]

The research on dielectric frequency response of oil-paper composite insulation modified by nanoparticles has been carried out in order to seek possible way to improve insulation properties thereof. Before and after nanoparticles being added, the dielectric frequency responses of oil-paper composite insulation with different moisture contents at different temperatures have been measured within the frequency from 0.1 mHz to 1 MHz. The Cole-Cole relaxation model has been used to analyzing the measured data. The results show that the variation rules of insulation condition can be indicated by the parameters of relaxation model. By adding nanoparticles, a new low frequency relaxation appeared. [ABSTRACT FROM AUTHOR]

The influence of moisture on the dielectric properties of different types of poly (ethyleneco- butyl acrylate) filled with alumina nanoparticles was systematically investigated by varying the type of aluminum oxide, particle surface treatment and filler content (2, 6 and 12 wt%). The nanoparticles were either unmodified or surface-treated with either aminopropyl triethoxysilane or octyltriethoxy silane. The complex permittivity was measured with an IDA200 dielectric spectroscopy analyzer at applied voltage of 200 Vpeak with frequencies varying between 1 mHz and 1 kHz. The measurements were performed at 25°C and relative air humidities of 24, 54 and 86 %. In order to expand the frequency range the HP 4284A precision LCR meter was used for measuring sample impedance at the frequency range of 100 Hz to 1 MHz. From the frequency dependence of dielectric losses it can be seen that absorbed water plays a significant role in determining the dielectric properties of the nanocomposites. The magnitude of tan ? seems to be determined primarily by the particle size and filler content, while the peak frequency is mostly influenced by the amount of absorbed water and the type of particle coating. [ABSTRACT FROM AUTHOR]

The dielectric properties of poly (ethylene-co-butyl acrylate) with 13 wt% of butyl acrylate (EBA) filled with alumina nanoparticles were studied as a function of particle size, particle coating, filler content (2, 6 or 12wt%) and temperature. The particles were either unmodified or surface-treated with either aminopropyltriethoxy silane or octyltriethoxy silane. The complex permittivity was measured with frequencies varying between 1 mHz and up to 1 kHz at different temperatures (25, 45 and 65°C). Measurements were performed in dry conditions. From the dielectric spectroscopy measurements it can be seen that the tan ∂ for the dry samples is almost independent of the type of the particle coating used. It does, however, depend on the particle size, filler content and temperature. [ABSTRACT FROM AUTHOR]

An inverter surge resistant enameled wire was developed with innovative organic/inorganic nanocomposite insulating material by dispersing an inorganic material at a nanometer level. It successfully achieved satisfactory levels for both partial discharge resistance and coating film flexibility and strength. This product can maintain a voltage endurance of more than 1000 times as high as those offered by general enameled wires even after mechanical stress is applied. This paper describes how the product can dramatically improve the reliability of magnet wires and open the way for performance warrant of inverter-fed motors in actual operation up to a surge voltage around 1.5 kVp. [ABSTRACT FROM PUBLISHER]