Preparation and characterization of ethylene-vinyl acetate/ halloysite nanotube nanocomposites Hossein Cheraghi Bidsorkhi • Hossein Adelnia • Raheleh Heidar Pour • Mohammad Soheilmoghaddam Received: 23 September 2014 / Accepted: 4 February 2015 Ó Springer Science+Business Media New York 2015 Abstract Ethylene-vinyl acetate (EVA) nanocomposites based on halloysite nanotubes (HNT) were prepared by solution casting method. The thermal, mechanical, water uptake, as well as oxygen permeability properties of the nanocomposites were examined. X-ray diffraction (XRD) and field emission scanning electron microscopy showed that HNTs were dispersed well into the EVA matrix. XRD data also suggested that HNT frustrates chain ordering and reduced total crystallinity percentage. The thermal and mechanical properties of the nanocomposites were im- proved with HNT loading, up to 3 wt%. Both ductility and toughness were enhanced by incorporation of up to 3 wt% of HNT, implicitly confirming that HNT has been dis- persed in EVA homogeneously. The addition of HNT also enhanced the water resistance and oxygen permeability of the prepared nanocomposites. Introduction In the last several years, polymer nanocomposites based on nanofillers have attracted a great deal of both academic and industrious attention. The deep interest in polymer nanocomposites is originated from the high surface area of the nanofillers, and favorable interactions between the ma- trix/nanofiller which in turn result in the improved properties including thermal stability, flame retardancy, mechanical properties, gas barrier properties, and so on as compared with neat polymers. In addition, polymer nanocomposites have an advantageous over convectional composites and that is the fact that in a much lower amount of nanofiller loading, the improved properties can readily be obtained. Recently, much effort has been performed on the incor- poration of nanofillers such as titanium oxide [1], graphene oxide [2], carbon nanotube [3], layered silicates [4], etc., in polymer matrix. Among them, layered silicates have drawn much attention due to their inexpensiveness, availability, as well as providing enhanced properties. Halloysite nanotubes (HNT) as a naturally occurring aluminosilicate with the molecular formula of Al 2 (OH) 4 Si 2 O 5 (2H 2 O) is one of the most promising types of layered silicates [5–8]. HNT possess unique features, distinguishing it from its other counterparts. Features such as (i) having a crystal structure identical to CNT, resulting in a high aspect ratio (length, inner, and outer diameters are 300–1500, 15–100, and 40–120 nm, respec- tively), (ii) having a low density of hydroxyl groups on its external surface, lowering its surface energy, and in turn, reducing the extent of filler/filler aggregation [9–11]. The latter characteristic enables one to incorporate HNT into H. C. Bidsorkhi Research Center on Nanotechnology Applied to Engineering of Sapienza (CNIS), Sapienza University of Rome, Rome, Italy H. C. Bidsorkhi Department of Astronautic, Electrical and Energetic Engineering, Sapienza University of Rome, via Eudossiana 18, 00184 Rome, Italy H. Adelnia Department of Polymer Engineering and Color Technology, Amirkabir University of Technology, Tehran, Iran R. Heidar Pour Department of Polymer Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru, Johor, Malaysia M. Soheilmoghaddam (&) Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 46150 Bandar Sunway, Selangor, Malaysia e-mail: moghaddam.farhad@gmail.com; m.soheilmoghaddam@monash.edu 123 J Mater Sci DOI 10.1007/s10853-015-8891-6