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Prepared Films (prepared + film)

Distribution by Scientific Domains

Physics and Astronomy	60%
Polymers and Materials Science	40%

Selected Abstracts

Polymers derived from N -isopropylacrylamide and azobenzene-containing acrylamides: Photoresponsive affinity to water

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2004
Haruhisa Akiyama
N -Isopropylacryamide was copolymerized by free-radical polymerization with N -[2-(4-phenylazophenoxy)ethyl]acrylamide derivatives that were substituted at their 4,-position with ethoxy, methoxyethoxy, or isopropyl units, or with N -{2-[4-(pyridin-2-ylazo)phenoxy]ethyl}acrylamide. The polymers were soluble in cold water and possessed lower critical solution temperatures (LCSTs). The value of the LCST rose a few degrees after UV irradiation and dropped after irradiation with visible light, reversibly, in processes that corresponded to the isomerization of the azobenzene units. The polymers became increasingly hydrophobic after increasing their azobenzene content. The difference of hydrophobicity correlates with the absorption band height at about 400 nm. The structure of the substituent on the azobenzene unit affected both the transition temperature and the hydrophobicity. A change in photoinduced wettability for water was observed to occur on a prepared film at a temperature different from the LCST determined in water. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5200,5214, 2004 [source]

DC conduction in bis(dimethylglyoximato)palladium(II) thin films

CRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2007
A. A. Dakhel
Abstract Bis(dimethylglyoximato)palladium (II) complex thin films of polycrystalline structure were prepared by sublimation in a vacuum at 140°C on p-Si substrates. After carrying out the characterisation of the prepared films by X-ray diffraction and X-ray fluorescence methods, Al-complex-Si MIS devices were fabricated. The constructed MIS structure was characterised by measuring the capacitance as a function of gate voltage at 1 MHz. The dependence of dc-current density on gate voltage and temperature in the range of 293 - 328 K of the MIS device was measured. It was found that the experimental data follow the trap-charge-limited space-charge-limited conductivity mechanism, from which the total concentration and the exponential energy distribution of the trap density were determined. In general, the measured quantities suggest that the conduction can be realised by thermally assisted hopping between localised states bundled in a very narrow band lying energetically near the mobility band edge. Moreover, results show that it is possible to use a film of the complex in applications of low-k dielectric material. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Ag,Ag0.08V2O5·nH2O composite films as host materials for Li+ intercalation

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2005
Ying Wang
Abstract We have prepared Ag,Ag0.08V2O5·nH2O composite films by dispersing Ag nanowires into V2O5·nH2O sol and have investigated electrochemical properties of the films for Li+ -ion intercalation applications. With the molar ratio of Ag nanowires to V2O5·nH2O as 0.1, such prepared films are composed of metallic Ag nanowires embedded in the matrix of Ag0.08V2O5·nH2O, due to partial Ag reacted with V2O5·nH2O. At a current density of 85 mA/g, such Ag,Ag0.08V2O5·nH2O film can intercalate about two equivalents of Li ions and delivers twice the capacity of the V2O5·nH2O xerogel film. Such improved electrochemical performance is ascribed to the changes in the microstructure and crystallinity of the Ag,Ag0.08V2O5·nH2O films including (i) further amorphization of V2O5·nH2O, (ii) increased porosity, and (iii) enhancement of electrical conductivity. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Thin film formation by rf sputtering with EuGa2S4 target and photoluminescence of the prepared films

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 8 2006
M. Dohi
Abstract Thin films were deposited on Si and fused quartz substrates by rf sputtering with EuGa2S4 target. The deposited films were annealed in the mixed atmosphere of S and He, which led crystallization of the film from amorphous phase. Photoluminescence of the annealed films, characteristic to the Eu2+ ion, was observed with room temperature quantum efficiency of 17%. Decay time constants at room temperature and liquid nitrogen temperature were measured to be 140 ns, and 430 ns, respectively. The latter value is close to the reported radiative lifetime of the EuGa2S4 crystal. Construction possibility of a surface-emitting laser is discussed with data on behaviour of excitation intensity dependent time-resolved spectra under pulsed laser excitation and on surface roughness of the film. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Melt processed microporous films from compatibilized immiscible blends with potential as membranes

POLYMER ENGINEERING & SCIENCE, Issue 4 2002
M. Xanthos
Microporous flat films with potential as membranes were produced via melt processing and post-extrusion drawing from immiscible polypropylene/polystyrene blends containing a compatibilizing copolymer. The blends were first compounded in a co-rotating twin-screw extruder and subsequently extruded through a sheet die to obtain the precursor films. These were uniaxially drawn (100%,500%) with respect to the original dimensions to induce porosity and then post-treated at elevated temperatures to stabilize the resultant structure, which consisted of uniform microcracks in the order of a few nanometers in width. The effects of blend composition and extrusion process parameters on surface and cross-sectional porosity and solvent permeability of the prepared films are presented and related to specific microstructural features of the films before and after drawing. Finite element modeling of the stretching operation in the solid state yielded a successful interpretation of the blend response to uniaxial tension that resulted in microcrack formation. Comparison of some of the novel microporous structures of this work with commercial membranes prepared by solvent-based phase inversion processes suggests comparable pore size and porosity ranges, with narrower pore size distribution. [source]