فهرست مطالب

Progress in Color, Colorants and Coatings - Volume:10 Issue: 2, 2017
  • Volume:10 Issue: 2, 2017
  • تاریخ انتشار: 1396/03/17
  • تعداد عناوین: 6
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  • Mohammad Mahdi Salehi, Maryam Ataeefard, Siamak Moradian* Page 73
    Polypropylenes loaded with different alkyl ammonium-modified montmorillonite are prepared to utilize a melt-mixing technique in various ways. Two types of polypropylene and compatibilizer are incorporated to improve the dispersion of various types of nanoclay and the dyeing behavior of the nanocomposites with various disperses, so acid and basic dyes were studied. For the first time, the aim of this study was to investigate the effect of operational and material parameters in dyeing behavior and color buildup of producing nanocomposite due to better understanding of the dyeability mechanism of PP/nanoclay composite. The extent of exfoliation and dispersion of the nanoclay in PP was analyzed by XRD and TEM analytical techniques and the dyeability was studied through color build up and spectrophotometric measurement. The results showed that the mixing condition had not any significant effect on dyeability and lower the molecular weight of polypropylenes and that the compatibilizer causes better dyeability. The most intercalated nanocomposite also showed better dyeability and within various types of dye, disperses dye showed better dyeability. All things considered, it is appeared that between the two mechanisms suggested for dyeing improvement in the PP/nanoclay composite, the dominant mechanism is creating the path.
    Keywords: Dyeability, Polypropylene, Nanocomposite, Nanoclay
  • Alireza Grayeli Korpi *, Khatereh Maryam Bahman Pour Page 85
    Nickel films of 150 nm thickness were deposited on 304 stainless steel and post annealed under flow of nitrogen at different temperatures. The prepared samples were corrosion tested in 1.0 M H2SO4 solution using potentiodynamic polarization technique.
    Crystallographic and morphological structure of the samples were analysed by X-ray diffraction XRD and atomic force microscopy AFM respectively before corrosion test, and scanning electron microscope SEM after corrosion test. A clear correlation between the physical analyses XRD, AFM and SEM and the potentiodynamic results is achieved. The variation of corrosion resistance of the samples showed that the optimum annealing temperature is 673 K.
    Keywords: Ni thin films, annealing, nitriding process, Stainless steel, Corrosion
  • Ashwin Kumar Malviya, S.P. Tambe Page 93
    In corrosion protection study, it is important to develop economically attractive test method for mitigation of corrosion damage of coated structure. Faster predication of protective behavior of any coating is a big challenge for the coating industries. In present work, in-house waterborne anticorrosive coating system was selected for study. The corrosion protection of coating evaluated as per ISO12944-C3-High which includes salt spray ISO 9227, 480h and quick condensation test ISO6270, 240h. The exposure period was extended up to 1000 h for further monitoring of deterioration of selected coating system. In view of early predication of coating performance, different accelerated test exposure condition were designed in laboratory, such as; thermal aging in distilled water 50°C and 80°C, chemical immersion H2SO4 and NaOH, wet-dry cycle and thermal cycling. The corrosion protection properties of coating exposed to ISO 12944-C3-High environment was compared against the lab designed test method using electrochemical impedance spectroscopy EIS technique. The deterioration rate of coating was measured by evaluating polarization resistance Rp, water uptake w and break point frequency Fb. The coated specimens after exposure were also evaluated for loss of adhesion strength. Results showed that thermal aging in distilled water at 80°C is the most severe exposure condition as coating system loses its protective behavior in relatively short period.
    Keywords: accelerated corrosion, break point frequency, corrosion, electrochemical impedance spectroscopy, epoxy, Waterborne coating
  • Josef Sedlacek, Barbara Nevrla, Karel Neufuss, Pavel Ctibor Page 105
    Several silicate materials were plasma sprayed and characterized by the authors in recent years from the point of view of their chemical and phase compositions, microstructure and mechanical as well as thermal properties. Present work is concerned with selected dielectric properties of these deposits. Synthetic mullite and steatite as well as natural olivine-forsterite were plasma sprayed using the water-stabilized plasma system WSP®. The deposits were striped-out, ground and polished to produce samples in form of plates with a smooth surface. Part of samples was later annealed in air. These samples – after coverage by metal electrodes functioning as monoblock capacitors – were tested in the alternative low voltage electric field to measure capacity and loss factor in the frequency range from 200 Hz to 1 MHz. Relative permittivity was calculated from the measured capacity. Volume resistivity was measured in the direct electric field. It is shown that the relative permittivity of plasma as-sprayed silicates is less stable compared to bulk in the whole studied frequency range. However, thermal annealing modifies the structure much closer to the sintered bulk. This is reflected also in dielectric properties. Insulating ability of plasma-sprayed silicates with and without annealing is discussed in consequence with chemical changes and phase changes induced by annealing.
    Keywords: Annealing, Dielectric properties, Plasma spraying, Silicates
  • Ali Hamidi, Kumars Seifpanahi-Shabani *, Mohammad Karamoozian Page 115
    In this paper, the results of studies of the sorption activity of Salvadora Persica fine particles that were provided from internal natural resources at Iran, with respect to Crystal Violet, Basic Violet-16 and Basic Blue-41 dyes were presented. Thus, Salvadora Persica particles were modified and prepared via particle size decreasing and characterized by CHNS, XRD, SEM and FT-IR analysis. In the batch system the influence of pH, adsorbent dosages and dye initial concentration was investigated. The results of isotherm and kinetics studies show that the Langmuir isotherm and pseudo-second order kinetic have better correlation with the experimental data. Calculations of thermodynamic parameters show negative Gibbs free energy ∆G values or spontaneous reaction, the enthalpy ∆H changes shows the exothermic process and values of entropy ∆S indicate low randomness at the solid/solution interface during the uptake of dyes. So, these locally available cheap adsorbent for the removal of basic dyes from the aqueous solution has high efficiency, also can be utilized for other water pollutants such as toxic elements.
    Keywords: Salvadora Persica, Basic Dyes, Adsorption, Wastewater Treatment
  • Mozhgan Hosseinnezhad, Kamaladin Gharanjig *, Samaneh Belbasi, Seied Hadi Seid Saadati Page 129
    An ecological approach has been obtained by using natural dyes and mordant for dyeing process. Silk fabrics dyed using natural mordants: powder of sour pomegranate and sweet pomegranate and mixture them. A beautiful red color were obtained by using theses mordants. The color of dyed silk fabrics was investigated in CIE Lab L, a and b and K/S values. Finally, all dyed fabrics were tested for wash and light fastness properties as per ISO standard test methods. The results of using biomordants for silk dyeing were comparable with that of the metallic mordants in terms of color strength and fastness properties. Pomegranate extract as biomordants produced red color with medium fastness properties and thus offer full potential to replace metal salts in silk dyeing process.
    Keywords: Natural dyeing, Pomegranate, Biomordant, Extraction, Fastness