Polyimide/polyaniline nanofiber composites were prepared by in situ polymerization with various weight percentages of polyaniline (PANI) nanofibers. X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR), proved the successful preparation of PANI nanofiber composite films. In addition, thermal stability of PI/PANI nanofiber composites was superior relative to PI, having 10 % gravimetric loss in the range of 623 °C to 671 °C and glass transition temperature of 289 °C to 297 °C. Furthermore, the values of the loss tangent tanδ and AC conductivity σAC of the nanocomposite films were notably higher than those of pure polyimide. The addition of 5 wt.% to 15 wt.% PANI nanofiber filler enhanced the activation energy of PI composites from 0.37 eV to 0.34 eV.
In this research we prepared CdS thin films by Spray pyrolysis method on a glass substrates and we study its structural , optical , electrical properties .The result of (X-Ray ) diffraction showed that all thin films have a polycrystalline structure , The relation of the transmission as a function of wavelength for the CdS films had been studied , The investigated of direct energy gap of the CdS its value is (2.83 eV). In Hall effect measurement of the CdS we find the charge carriers is p – type and Hall coefficient 1157.33(cm3/c) ,Hall mobility 6.77(cm2/v.s)
Aim To develop a low-density polyethylene–hydroxyapatite (HA-PE) composite with properties tailored to function as a potential root canal filling material. Methodology Hydroxyapatite and polyethylene mixed with strontium oxide as a radiopacifier were extruded from a single screw extruder fitted with an appropriate die to form fibres. The composition of the composite was optimized with clinical handling and placement in the canal being the prime consideration. The fibres were characterized using infrared spectroscopy (FTIR), and their thermal properties determined using differential scanning calorimetry (DSC). The tensile strength and elastic modulus of the composite fibres and gutta-percha were compared, dry and after 1 month storage in
... Show MoreThe present work involved four steps: First step include reaction of acrylamide ,N-?-Methylen-bis(acryl amide) and N-tert Butyl acryl amide with poly acryloyl chloride in the presence of triethyl amine (Et3N) as catalyst, the second step include homopolymerization of all products of the first step by using benzoyl peroxide(BPO) as initiator in (80-90)Co in the presence of Nitrogen gas(N2). In the third step the poly acrylimide which prepare in second step was convert into potassium salt by using alcoholic potassium hydroxide solution. Fourth step include Alkylation of the prepared polymeric salts in third step by react it with different alkyl halides(benzyl chloride, allylbromide , methyl iodide) by using DMF as solvent for(10-12) hours.
... Show MoreIn this study , Iraqi Bentonite clay was used as a filler for polyvinyl chloride polymer. Bentonite clay was prepared as a powder for some certain particle size ,followed by calcinations process at (300,700,900) OC ,then milled and sieved. The selected sizes were D ~75 µm and D ~150. After that polyvinyl Al-Cohool solution prepared and used as a coated layer covered the Bentonite powder before applied as a filler ,followed by drying , milling and sieving for limited recommend sizes. polyvinyl chloride solutions were prepared and adding of modified Bentonite power at certain quantities were followed .Sheet of these variables on the mechanical and thermal properties of the prepared reinforced particular polyvinyl chloride composite
... Show MoreThin films of (CdO)x (CuO)1-x (where x = 0.0, 0.2, 0.3, 0.4 and 0.5) were prepared by the pulsed laser deposition. The CuO addition caused an increase in diffraction peaks intensity at (111) and a decrease in diffraction peaks intensity at (200). As CuO content increases, the band gap increases to a maximum of 3.51 eV, maximum resistivity of 8.251x 104 Ω.cm with mobility of 199.5 cm2 / V.s, when x= 0.5. The results show that the conductivity is ntype when x value was changed in the range (0 to 0.4) but further addition of CuO converted the samples to p-type.
This paper addresses the substrate temperature effect on the structure, morphological and optical properties of copper oxide (CuO) thin films deposited by pulsed laser deposition (PLD) method on sapphire substrate of 150nm thickness. The films deposited at two different substrate temperatures (473 and 673)K. The atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and UV-VIS transmission spectroscopy were employed to characterize the size, morphology, crystalline structure and optical properties of the prepared thin films. The surface characteristics were studied by using AFM. It is found that as the substrate temperature increases, the grain size increased but the surface roughness decreased. The FTIR spec
... Show MoreThe paper reports the influence of the thickness on the some optical properties of Fe2O3 thin films,which were prepared by chemical Spray pyrolysis technique on glass substrate heated to 400˚c.The thickness of thin films (250,280,350)nm were measured by using weighting method. The optical properties include the absorbance and reflectance spectra,extinction coefficient,and real and imaginary part of the dielectric constant.The result showed that the optical constant(k,εr,εi)decreased with the increase of the thickness.
This study aims to prepare Cadmium Sulphide (CdS) thin films using thermal Chemical Spray Pyrolysis (CSP) on glass of different temperatures substrate from cadmium nitrate solution. Constant thickness was (430 ± 20 nm) and the effect of substrate temperature on the optical properties of prepared thin films.
Optical properties have been studied from transmittance and absorbance spectral within wavelengths range (360 - 900 nm). The results show that all the prepared films have a direct electron transitions and optical energy gap between (2.31-2.44 eV). They also show that the transmittance and optical energy gap of films prepared from nitrate solution increase with increasing of substrate temperature, then transmittance start do
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