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In this study, carbon nanotubes (CNTs)/ZnO composites had been prepared using the sol-gel method and then incorporated into an epoxy resin for reinforcement of mechanical and electrical properties. Fourier Transform Infrared (FTIR), X-ray diffraction (XRD) Field Emission Scanning Electron Microscope (FE-SEM) analyses show that the ZnO nanoparticles deposited on CNTs were crystallized in a hexagonal wurtzite structure. Average particle size of ZnO deposited on the CNT was about 8 nm. The mechanical and dielectric properties of epoxy containing CNTs/ZnO were investigated in comparison to epoxy resin and epoxy resin containing only CNT or ZnO nanoparticles. The results indicated that tensile strength and elongation at break of the nanocomposite were substantially improved with the presence of CNTs/ZnO at the equal volume. The DSC analysis associate with the dielectric results shows that the behavior of epoxy/CNTs/ZnO is identical to epoxy/ZnO composite, and the CNTs is essential to the distributed arrangement of ZnO in the epoxy resin.

In this work, graphene oxide (GO) was prepared by modified Hummer's method. Polyurethane coatings with different GO concentrations (0.1‐0.5 %) were prepared for corrosion protection of carbon steel. Synthesized GO was characterized by FTIR and XRD. Corrosion resistance of polyurethane coatings containing GO was investigated by electrochemical impedance spectroscopy and salt fog test. The effects of GO on protection performance of polyurethane coatings depended on its dispersion ability. GO at a concentration of 0.1 % significantly improved corrosion resistance of polyurethane coatings.

This study investigates the durability of polyurethane coating containing graphene oxide under UV radiation. In this work, graphene oxide (GO), as an UV absorber, was fabricated by Hummer's method. The structure and morphology of GO were characterized by Fourier transform infrared spectroscopy (FT‐IR), Field emission scanning electron microscopy (FESEM) and Ultraviolet‐vision spectroscopy (UV‐Vis). The results showed that GO with layered structure was successfully synthesized. GO was incorporated into polyurethane coating at a concentration of 0.1 wt.%. Gloss measurement, colorimetric measurement and electrochemical techniques were used to evaluate the degradation of polyurethane coating containing GO after exposure to QUV test. The results indicated that presence of GO enhanced the UV durability of polyurethane coating.

This work reports on the mechanical and dielectric properties of waterborne epoxy coatings containing polyaniline/silica nanocomposites (PANi/SiO2). The nanocomposites with different PANi/SiO2 ratios were synthesized by in-situ chemical oxidative polymerization method. The morphology and electric properties of PANi/SiO2 were examined by field emission scanning electron microscopy (FESEM) and standard four-probe electrode method. It was shown that the silica nanoparticles were grafted by PANi and it conducted a decrease of electrical conductivity of PANi/SiO2 composites, compared to pure PANi. The epoxy coatings containing PANi/SiO2 presented lower dielectric properties than that containing pure PANi. In contrast, the PANi/SiO2 could maintain the breakdown voltage (from 16.6 to 19.1 kV/mm) and enhance impact resistance of conducting epoxy system up to 100 kg.cm. The results revealed that the PANi/SiO2 nanocomposite can be used in electrical coating application with good dielectric strength and mechanical properties.

In this paper, a potentiality of magnetic expanded graphite material (EG@CoFe2O4) for the adsorptive removal of Congo red, an anionic azo dye, from aqueous solution was studied. The experiments were carried out in batch mode in which various experimental conditions including contact time, initial dye concentration, adsorbent dosage and pH were varied and their influences on the adsorption yield were investigated. The surface of the adsorbent before and after the removal of the dye was characterized by using FT-IR analysis. Maximum adsorption of dye was achieved at pH 6. The adsorption capacity of Congo red onto EG@CoFe2O4 was found to be as high as 101.2 (mg/g), which is higher than the adsorption capacity of the CoFe2O4 (45.7 (mg/g)). These results suggested the use of expanded graphite materials as an efficient adsorbent for decontamination of Congo red dye from factory effluents.

The polyurethane coatings containing phenylsilane groups (PU-S) were prepared by using the hydrolyzed triethoxyphenylsilane (TEPS). The synthesized PU-S coatings were characterized by Fourier Transform Infrared (FTIR). Mechanical properties and contact angle of PU-S coatings with different TEPS concentrations (1 %, 5 % and 10 %) were also studied. Electrochemical impedance spectroscopy (EIS) and salt spray test were carried out to evaluate corrosion resistance and the macroscopic failures of the coatings. The results show that the presence of TEPS in polyme matrix improved mechanical properties and corrosion protection performance of polyurethane coating.