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Charge Storage (charge + storage)

Distribution by Scientific Domains
Polymers and Materials Science100%

Selected Abstracts

Charge storage of electrospun fiber mats of poly(phenylene ether)/polystyrene blends

POLYMER ENGINEERING & SCIENCE, Issue 12 2009
Deliani Lovera
Nonwoven fiber mats composed of poly(phenylene ether) (PPE) and polystyrene (PS) blends were prepared by electrospinning of PPE/PS solutions in a mixture of chloroform and hexafluoroisopropanol. The blends showed higher electrospinnability and led to thinner fibers (200 nm,1.3 ,m) than the pure components, because of a proper balance of electrical conductivity and interaction with the electrospinning solvent. The charge retention of the electrospun fibers was evaluated and related to the blend composition and the electret properties of the components. It was found that the nonwoven mats were able to retain up to 60% of the initial surface potential after several days of annealing at temperatures as high as 140°C, which is markedly higher than the charge retention of corona-charged compact films. The capability of the electrospinning technique, to inject charges into the bulk of the material and to orientate the dipoles of the PPE phase in the field direction at the same time, was related to the good surface potential stability of the PPE/PS electrospun fiber mats. The possibility of creating thin PPE/PS fibers with excellent charge retention capabilities makes these materials ideal candidates for electret filter and sensing applications. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source]

Nonvolatile Memory Concepts Based on Resistive Switching in Inorganic Materials

ADVANCED ENGINEERING MATERIALS, Issue 4 2009
Thomas Mikolajick
Abstract Solid state memories play an important role for the electronic systems used in today's information society. The classical approach of charge storage is expected to reach its physical scaling limits very soon. New storage effects are therefore receiving significant interest from industry and academia. In the paper we summarize recent results on resistive switching effects in inorganic materials obtained in the research groups of the authors. We discuss the implications of these results for the suitability of the investigated material systems as well as for the direction of further research. [source]

Optical and thermo electrical properties of ZnO nano particle filled polystyrene

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010
Mulayam S. Gaur
Abstract The study of optical and thermally stimulated electrical properties such as optical band gap, refractive index, X-ray spectra, SEM spectra, thermally stimulated discharge current (TSDC), differential scanning calorimetry (DSC) have been undertaken in ZnO nanoparicle filled polystyrene nanocomposite thin film of 30 ,m thickness. The appearance of single TSDC peak at temperature 408 ± 5 K in nanocomposite samples shows the charge carriers injected from deeper trapping levels. It is due to the modification of surface and bulk properties of polystyrene by filling of ZnO nanoparticles. In other hand, the strong interaction of nanoparticles with polymer matrix is the expected reason of improvement of crystallite size, optical energy band gap, refractive index, TSDC, glass transition temperature, and charge storage. It is confirmed from SEM images that the modifications of these properties are caused by creation of clusters in amorphous,crystalline boundaries of pristine polystyrene. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source]

Preparation of polyaniline/vermiculite clay nanocomposites by in situ chemical oxidative grafting polymerization

POLYMER INTERNATIONAL, Issue 5 2009
Zhaobin Tang
Abstract BACKGROUND: Recently, conducting polymers have attracted much attention, since they have interesting physical properties and many potential applications, such as in conductive coating charge storage. Hence the synthesis of conducting polymer nanocomposites is also an area of increasing research activity. RESULTS: Vermiculites (VMTs) were successfully delaminated using an acid treatment. Polyaniline (PANI)/VMT nanocomposites were prepared by in situ chemical oxidative grafting polymerization. CONCLUSION: The chemical grafting of PANI/VMTs was confirmed by Fourier transform infrared and UV-visible spectroscopy. The percentage of grafted PANI was 142.7 wt% as a mass ratio of the grafting PANI and charged nano-VMTs, investigated using thermogravimetric analysis. In addition, characteristic agglomerate morphology of PANI was observed in the composites using scanning electron microscopy. Thermal analyses indicated that the introduction of VMT nanosheets had a beneficial effect on the thermal stability of PANI. The electrical conductivity of the nanocomposites was 3.9 × 10,3 S cm,1, a value typical for semiconductors. Copyright © 2009 Society of Chemical Industry [source]