PROGRESS IN COLOR, COLORANTS AND COATINGS
Year:2017 | Volume:10 | Issue:1 |Papers Count:6

oxidation behavior of AZ91D magnesium alloy with 3YSZ coating and aluminum interlayer was studied in air at 250 ° C using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The oxidation process was carried out in various times from 1 to 10 h. A three-electrode electrochemical cell was employed for all the EIS measurements. Also, to focus on the characteristics of the oxide films, a nonaggressive electrolyte (0. 1 M Na2SO4) was used. The EIS data were interpreted with a two-layered model, and the obtained capacitance and resistance are related to the thickness and defectiveness of YSZ coating and oxide film which was formed during the oxidation process. The results showed that after 6 h of oxidation time, the defects are produced in YSZ coating and it helps to increase the thickness of the oxide film. Also, XRD results revealed that the oxide films were mainly composed of Al2O3 and MgAl2O4 phases. The oxide film remained protective during extra oxidation period. In addition, the electrochemical model was supported by SEM observations. Prog. Color Colorants Coat. 10 (2017), 1-12© Institute for Color Science and Technology.

zinc sulfide/carbon nanofibers (ZnS/CNFs) composite was successfully synthesized through a facile and simple method. X-ray diffraction (XRD) patterns revealed the formation of ZnS decorated CNFs composite. The photocatalytic activity of ZnS/CNFs composite was investigated by the photodegradation of Rhodamine 6G (Rh-6G) dye in aqueous solutions. The effect of operational parameters such as initial Rh-6G concentration, ZnS/CNFs composite concentration, pH and irradiation time were analyzed and optimized by response surface methodology (RSM) in photocatalysis process. The results revealed that the removal percentage of Rh-6G increased with ZnS/CNFs composite concentration, pH and irradiation time, whereas higher initial dye concentration was unfavorable. The findings also showed that under optimum conditions (initial Rh-6G concentration=6 mgL-1, ZnS/CNFs composite concentration= 1. 25 g L-1, pH= 8 and irradiation time=48 min) and exposure of UV-C light irradiation (20 Wm-2), the ZnS/CNFs composite exhibited a remarkable photodegradation of Rh-6G dye in aqueous media (99. 17%). Prog. Color Colorants Coat. 10 (2017), 13-21© Institute for Color Science and Technology.

in this paper, polyacrylonitrile (PAN)-Titania (TiO2) electrospun nanofiber (PAN/TiO2 nanofiber) was prepared via a facile electrospinning method. The characteristics of the PAN/TiO2 nanofiber were investigated using SEM and FT-IR. The nanofiber showed retained nanofibrous structures and high photocatalytic efficiency under UV light for degradation of Direct Red 80 (DR80) and Direct Red 23 (DR23) in water. The photocatalytic dye degradation kinetics followed first-order model. The reaction rate constant (k) at 20 mg/L dye concentration was 0. 0184 min-1 for DR 80 and 0. 0328 min-1 for DR23. The dye degradation rate constant decreased by increasing initial dye concentration. The results indicated that polyacrylonitrile-Titania electrospun nanofiber could be used as a photocatalyst to decolorize colored wastewater. Prog. Color Colorants Coat. 10 (2017), 23-30© Institute for Color Science and Technology.

in the present work, attempts were made to investigate the reinforcement and treatment effect of glass flake (GF) on morphological and rheological behavior of GF/epoxy vinyl ester composites. GF was incorporated into epoxy vinyl ester resin by sonication and mechanical agitation. Rheological and morphological properties were studied as a function of flakes treatment and size distributions. The dispersion morphology, agglomeration degree and homogeneity of additives were analyzed by scanning electron microscopy (SEM) and optical microscopy. The effects of mixing method, surface treatment, and particle size distribution on rheological properties of composites were investigated with a modular compact rheometer. The results demonstrated that the mechanical agitation decreases GF aspect ratio more than sonication. SEM fractography confirms that finer particles improve toughness properties of the composites in comparison with larger ones. GF with larger circular diameter and length is more sensitive to shear than the smaller one. Rheological investigations showed that surface treatment improves the interaction between the polymer matrix and GF. Based on the results, it is indicated that the finer the GF, the better rheological properties will be displayed. Prog. Color Colorants Coat. 10 (2017), 31-41© Institute for Color Science and Technology.

in this paper we designed and prepared three free-metal organic dyes (Dye 1, Dye 2 and Dye 3) based on indoline with n-phenly substituted iminodibenzyl as the electron donor group. We used cyanoacrylic acid substituent as the electron acceptor anchoring group in organic dyes. The proposed dyes were prepared from iminodibenzyl as the starting material by standard reactions and characterized by different techniques such as melting point, FT-IR, 1HNMR, elemental analysis and UV-Visible spectroscopy after purification. Spectrophotometric measurements of the organic dyes in solution and on a photoanode substrate were carried out in order to assess status changes of the dyes. The wavelengths of maximum absorption for Dye1 to Dye 3 in solution are 416 nm, 421 nm and 409 nm and on photoanode substrate are 437 nm, 440 nm and 421 nm, respectively. Finally, the proposed dyes were used as sensitizer in a photoelectrochemical cell structure and their photovoltaic properties were also investigated. The conversion efficiency for Dye 1 to Dye 3 is 2. 84%, 3. 11% and 2. 12%, respectively. Prog. Color Colorants Coat. 10 (2017), 43-50© Institute for Color Science and Technology.

pigment Red 3 was synthesized and chemically treated by sulfonation. The treatment, affected the surface chemistry and the shape of pigments. The effects of reaction time, temperature, solvent/pigment ratio and acid/pigment ratio were examined on the treated pigment. The investigation of experimental design was carried out based on Taguchi method. UV-Visible spectroscopy, densitometry, turbidimetry, pH and Scanning Electron Microscopy were used to assess the treated particles. The effects of surface modification on properties of water born flexographic ink were studied using dispersion rate, gloss, chroma, hue, lightness and K/S of ink coating. Optimum samples were selected according to the results of the analyses as well as the Variance Analysis and by considering the effect of each independent parameter. Prog. Color Colorants Coat. 10 (2017), 51-65© Institute for Color Science and Technology.