Anticorrosion Epoxy Coating Enriched with Hybrid Nanozinc Dust and Halloysite Nanotubes Nima Moazeni, Zurina Mohamad, Nor Liyana Izzati Faisal, Mahsa A. Tehrani, Nazila Dehbari Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, Skudai Johor 81310, Malaysia Correspondence to: N. Moazeni. (E - mail: mnima2@live.utm.my or nima.moazeni@gmail.com) ABSTRACT: In this study, the performance of an epoxy coating with hybrid nanozinc dust and halloysite nanotube (HNT) fillers on the corrosion protection of a carbon steel substrate was investigated. The epoxy resin was mixed with a constant amount of nanozinc dust (1%) and different contents of HNTs (0, 0.5, 1, and 1.5%) with a high speed mixer. Fourier transform infrared spectroscopy and thermogravimetric analysis were used to analyze the interactions between the components in the coating material and the thermal sta- bility of the epoxy coating, respectively. Open-circuit potential, salt spray testing, and microscopy were also used to assess the corro- sion resistance of the carbon steel substrate coated with these coating materials. The incorporation of nanozinc in the epoxy coating enhanced the corrosion protection of the carbon steel substrate compared with the pure coating. Furthermore, HNTs further enhanced the corrosion protection. The best protection was achieved when 1% nanozinc and 1% HNT were used. V C 2013 Wiley Period- icals, Inc. J. Appl. Polym. Sci. 130: 955–960, 2013 KEYWORDS: coatings; resins; thermosets; clay Received 22 November 2012; accepted 17 February 2013; Published online 17 April 2013 DOI: 10.1002/app.39239 INTRODUCTION For centuries, professionals had been looking for a solution to reduce the corrosion of metals. Corrosion is the deterioration of metal that is caused by the reaction of the metal with the envi- ronment. 1 Paint and coatings are great solutions for preventing corrosion. One-third of the production of paint is used to pro- tect and decorate the metal surface. Paints and coatings can be divided into two categories, the convertible type, where they need a chemical reaction such as oxidation or polymerization, and the nonconvertible type, which are formed by the evapora- tion of the solvents. The former category includes alkyds, epoxy, esters, polyesters, urethanes, silicon, and other resins. 2 Generally, the resin that is often used for coatings is epoxy. This is due to its outstanding processability, excellent chemical resist- ance, strong adhesion, and affinity to heterogeneous materials. However, the major disadvantages of pure epoxy resins are their brittleness and low fracture toughness. 3 The mechanical and thermal properties of epoxy resin can be further enhanced by the addition of additives. A new world of additives has been explored with the prefix nano. Many researchers 4–9 have reported that the incorporation of nanofillers in the epoxy coat- ing structure results in increases in the barrier properties, ther- mal stability, fire resistance, transparency, color purity, and resistance to organic solvents and in a lower coefficient of linear expansion. Halloysite nanotubes (HNTs) are a kind of nanoclay that have been investigated as a type of additive and are mostly used as a reinforcement agent. Researchers 10,11 have reported that the use of HNTs in epoxies improved the properties of the resulting nanocomposites, such as the coefficient of corrosion protection, coefficient of thermal expansion, and modulus. Because of the polar nature of HNTs, they may have better compatibility with polar epoxy resin and are expected to be good reinforcement for epoxy binder. Liu et al. 10 showed that in a hybrid of epoxy resin with HNTs with increasing HNT content, the storage modulus increased, and this subsequently exposed excellent bar- rier properties of HNTs, which could ameliorate the corrosion protection of the substrate. On the other hand, zinc has been used widely as an anticorro- sive coating since 1840. This is due to the properties of zinc itself, which lead to a high anticorrosion efficiency. The incor- poration of zinc in epoxy resin (zinc-rich paint) is a well-estab- lished method for protecting metal by cathodic protection. 12,13 Kalendov a 11 reported that the smaller size zinc, such as nano- zinc exhibited a higher efficiency in anticorrosion compared to the large size zinc on the microscale. V C 2013 Wiley Periodicals, Inc. WWW.MATERIALSVIEWS.COM WILEYONLINELIBRARY.COM/APP J. APPL. POLYM. SCI. 2013, DOI: 10.1002/APP.39239 955