Synthesis of antistatic hybrid nanocomposite coatings using surface modified indium tin oxide (ITO) nanoparticles Mostafa Jafari, Azam Rahimi, Parvin Shokrolahi, Amir Ershad Langroudi Ó American Coatings Association & Oil and Colour Chemists’ Association 2014 Abstract Several antistatic nanocomposite hybrid coatings based on epoxy-silane developed by sol–gel method are studied. The hybrid sols are prepared by hydrolysis and condensation of GPTMS and TMOS precursors in the presence of an acid, as catalyst, and EDA as curing agent. Considering their good electrical conductivity, indium tin oxide (ITO) nanoparticles are used as antistatic agents. To improve the distribution/ dispersion of ITO nanoparticles in the polymer matrix, the surface of nanoparticles is modified with silane groups (m-ITO). The antistatic properties of the coat- ings, containing various amounts of m-ITO nanoparti- cles, are investigated through surface electrical resistivity measurements. FTIR is used to screen the reaction of epoxy groups and the effect of EDA on crosslinking in the hybrid coatings. Morphology, nano- particle distribution and surface roughness of the coat- ings are studied through SEM and AFM microscopy techniques. Also, homogeneous distribution of ITO nanoparticles within the polymer matrix is confirmed by EDXA elemental mapping. The cubic shape and nano- metric size of the nanoparticles in the hybrid coatings are monitored by transmission electron microscopy (TEM). Keywords Nanocomposite, Antistatic coatings, Hybrid, Organic–inorganic nanostructured material, ITO nanoparticles Introduction Hybrid materials as inorganic–organic nanostructure composites represent a new class of materials with interesting chemical and physical properties for many applications. Sol–gel process (offering a mild-process- ing condition, i.e., low temperature/pressure) is of special interest in fabrication of nanostructured mate- rials such as nanocomposite coatings carrying a variety of functionalities. 1–4 For more than a decade, sol–gel technique has been used to apply thin films as well as a variety of organic–inorganic hybrid nanocomposite coatings on different substrates including glasses of large surface area. This simple process does not need expensive equipment and also provides control over the density of the sol solution. 5–7 Zand et al. 8 have previously reported the prepara- tion of a coating based on 3-glycidoxypropyl-tri- methoxysilane (GPTMS), via sol–gel process. They showed that employment of a crosslinking agent resulted in brittleness and crack formation in the final hybrid coatings. Shanaghi et al. 9 prepared a uniform TiO 2 nanoparticle coating applied on mild steel, using sol–gel method. The coating was deposited on the substrate by dip coating and they reported an increase in resistance of TiO 2 nanoparticle coating against corrosion. Rivero et al. 10 have prepared an organic– inorganic hybrid matrix of tetraorthosilicate loaded with silver nanoparticles using an in situ synthesis route. They observed that the silver-loaded organic– inorganic hybrid films have a very good anti-microbial behavior against bacteria. Indium tin oxide (ITO) nanoparticles, being electri- cally conductive, are widely used in preparation of transparent and conductive films. 11–13 Coatings con- taining ITO nanoparticles (with a high surface to volume ratio) play an important role in many elec- tronic and optoelectronic devices in applications such as solar cells, 14 liquid crystal displays, 15 heat reflection mirrors, 16 flat panel displays, 17 gas sensors, 18 and antistatic coatings. 6 Psuja et al. and Senthilkumar 5,19–21 have separately investigated the influence of Sn con- centration on electrical properties of ITO-containing M. Jafari, A. Rahimi (&), P. Shokrolahi, A. E. Langroudi Iran Polymer and Petrochemical Institute, P.O. Box 14956/115, Tehran, Iran e-mail: a.rahimi@ippi.ac.ir J. Coat. Technol. Res., 11 (4) 587–593, 2014 DOI 10.1007/s11998-013-9555-6 587 Downloaded from http://www.elearnica.ir