فهرست مطالب

Progress in Color, Colorants and Coatings
Volume:10 Issue: 4, Autumn 2017

  • تاریخ انتشار: 1396/10/27
  • تعداد عناوین: 7
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  • Editorial Broad
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  • G.S. Sajadi, M. Shahidi, S.M.A. Hosseini, M.J. Bahrami Page 205
    In this work, polypyrrole/ZnO nanocomposite PPy/ZnO NC was produced through synthesis of polypyrrole polymer in the presence of ZnO nanoparticles. The corrosion behavior of polyvinyl butyral coatings without and with different weight percentages of nanocomposite on the surface of 7075 Al alloy was investigated in 3.5 NaCl solution at different times of immersion using electrochemical impedance spectroscopy EIS and electrochemical noise EN techniques. The coating with 0.025 PPy/ZnO NC revealed the highest corrosion resistance. In order to analysis of EN data, wavelet transform was used to obtain the standard deviation of partial signal SDPS plots. The good agreement between the EIS and EN results indicates that the EN technique, as well as the EIS method, can be used successfully for the corrosion evaluation of coatings.
    Keywords: Nanocomposite, Polyvinyl butyral, Electrochemical Impedance Spectroscopy, Electrochemical Noise, Wavelet Analysis
  • Rahebeh Amiri Dehkharghani, Faramarz Afshar Taromi, Hamidreza Cheghini, Yoram Tishbi, Nilofar Rezaee Page 217
    We have reported here a simple, low cost preparation of four new adducts from some anthraquinone disperse dyes with functionalized multi-walled carbon nanotubes in the presence of azochromophore. The structural differences between the final products are evaluated by visual dispersion test, UV-Vis Spectroscopy, Fourier transforms infrared, Raman, nuclear magnetic resonance and thermal gravimetric analysis. The morphology of themis detected using scanning electron microscopy. It has been shown that various substituents on the backbone of anthraquinone can affect the features of the adducts.
    Keywords: anthraquinone, azo, chromophore, dye, multi, walled carbon nanotube
  • P. Ctibor, J. Sedlacek, M. Janata Page 225
    Amultifunctional material, strontium zirconate, SrZrO3, studied in literatures as a dielectric ceramics, thermal barrier coating, proton-conductor, and luminescent material was sprayed by a water-stabilized plasma torch WSP 500. Stainless steel and plain carbon steel were used as substrates. Coatings with thickness of 1 to 2 mm were produced, whereas the substrates were preheated over 450 °C. The torch working at 150 kW was able to spray SrZrO3 with a spray rate of 10 kg per hour. Microstructure, phase composition, dielectric properties, and optical band gap were also investigated.
    Keywords: Plasma spraying, Electrical properties, Strontium Zirconate, Insulators
  • Authors: M. Khajeh Aminian, Tayebe Azizi, Reza Dehghan, Mohsen Hakimi Page 231
    Blue nano pigments of CoAl2O4 were successfully prepared by polyol method. Two different groups of materials containing chloride and acetate compounds were used to synthesis the nano pigments. The nano pigments were calcinated at 1100°C. The CoAl2O4 nano pigments were characterized by X-ray diffraction XRD, scanning electron microscopy SEM, diffuse reflectance spectroscopy DRS, dynamic light scattering DLS, UV–Vis spectroscopy and CIE-Lab colorimetric measurement. Dynamic light scattering analysis confirmed the formation of nanoparticles in the suspensions. XRD data of CoAl2O4 powders displayed the samples, were synthesized by acetate compounds, have been crystallized just in CoAl2O4 spinel structure. While the samples, were synthesized by chloride compounds, have been crystallized in two phases of CoAl2O4 and Al2O3 crystal structures. The SEM images showed the average size of nano CoAl2O4 pigments is about 50 nm for all nano pigments while they have some agglomerations. The colorimetric parameters and DRS spectra confirmed the formation of blue pigments in all samples. The purity and intensity of color for the samples were different
    Keywords: Polyol, Nano pigment, CoAl2O4, Chloride, Acetate
  • M. Hosseinnezhad, S. Moradian, K. Gharanjig Page 239
    In this paper we used two free-metal organic dyes dye 1 and dye 2 based on indigo and thioindigo with cyanoacrylic acid as the electron donor group. The proposed dyes were sensitized from naphalene as the starting material by standard reactions and characterized by different analytical techniques and UV-Visible spectroscopy after purification. Spectrophotometric measurements of the organic dyes in solution and on a TiO2 substrate were carried out in order to assess changes in the status of the dyes. The wavelength of maximum absorption for dye 1 and dye 2 in solution is 572 nm and 492.3 nm and on TiO2 films are 595 nm and 516.8 nm, respectively. Finally, the proposed dyes used as sensitizer in DSSCs and T-DSSCs structure and their photovoltaic properties investigated. The Conversion efficiency for dye 1 and dye 2 in DSSCs and T-DSSCs are 3.45 and 6.45 and 4.09, respectively.
    Keywords: Dye, sensitized solar cells, Tandem, Organic dyes, Light harvesting, Small sensitizers
  • Mohammad Reza Saeb, Henri Vahabi, Maryam Jouyandeh, Reza Khalili, Elnaz Movahedifar Page 245
    This work presents a study on the flammability of epoxy coatings containing two types of nano-scale fillers as potential flame retardants: expandable graphite EG and halloysite nanotubes HNTs. Both nanocomposites are prepared by incorporation of the same amount of nanofiller into the epoxy resin for the sake of comparison. Fire retardant nanocomposite coatings are cured through a two-stage procedure in a mold and oven, respectively. The cone calorimeter test is performed to investigate the effect of using these flame retardants on the peak of Heat Release Rate pHRR, Total Heat Release THR, Total Smoke Production TSP and Time-To-Ignition TTI. It was found that the thermal behavior of blank epoxy and epoxy/EG was quite different and loading EG leaded to a significant fall in pHRR. In the presence of EG, the thin layer of residue was formed at first stages of ignition, grown rapidly and became denser acting as a strong barrier against fire. This barrier could retard the burning and doubled the total time of burning. By contrast, HNTs could not affect as an efficient flame retardant in the epoxy-based coating. Even by high loading level of 9 wt., HNT could not influence pHRR, TTI and THR parameters.
    Keywords: Epoxy coating, Flame retardancy, Nanocomposites, Expandable graphene, Halloysite nanotubes