Material properties Thermo-mechanical properties of poly (vinyl chloride)/ graphene oxide as high performance nanocomposites Kalim Deshmukh, Girish M. Joshi * Polymer Nanocomposite Laboratory (PNL), Material Physics Division, School of Advanced Sciences, VIT University, Vellore 632014, TN, India article info Article history: Received 17 December 2013 Accepted 28 January 2014 Keywords: GO PVC Nanocomposites Nanofiller Mechanical properties Dielectric properties abstract Graphene oxide (GO) reinforced polyvinylchloride (PVC) nanocomposites were prepared by colloidal blending. Free standing PVC/GO nanocomposite films were used for me- chanical, thermal and electrical characterization. It was observed that the strong interac- tion between PVC and GO via covalent bonding can help in achieving excellent reinforcement of a PVC matrix for fabrication of high performance nanocomposites. A significant improvement in the mechanical properties was observed as a function of GO loading. The tensile strength and Young’s Modulus of the nanocomposite films was increased whereas (%) elongation was decreased by 32.15% as a function of GO loading. The improvement in mechanical properties may be due to homogeneity of the nanocomposites and strong interfacial interaction between GO and PVC matrix. Incorporation of GO into PVC matrix results in an improvement in the thermal stability of the composite films, as demonstrated by TGA analysis. The dielectric properties were investigated in the frequency range from 50 Hz to 35 MHz and temperature 40–150  C. The electrical properties of composite films demonstrated stability in polarization across wide ranges of frequency and temperature. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction Reinforcing carbon allotropes in the form of conducting carbon black, carbon nanotubes (both single and multi- wall), graphite, graphene oxide (GO) and reduced graphene oxide (RGO) has been used extensively for preparation of polymer composites because of their outstanding proper- ties. The modified polymer moiety in the composites demonstrates remarkable enhancement of material prop- erties, including mechanical, thermal, optical and gas bar- rier properties, as compared to the virgin polymers. To develop high performance materials to pursue engineering applications, one has to understand the improvements in polymer nanocomposites. There are several key factors, such as degree of dispersion, interfacial adhesion and orientation, to be considered for successful fabrication of polymer composites containing GO, graphene, chemically or thermally reduced graphene (RGO) or functionalized graphene sheets to take advantage of their unique structure and physical properties. High performance polymer nano- composites with improved functional, mechanical and dielectric properties [1–4] can be obtained by successful incorporation of GO and graphene into the polymer matrix. The homogeneous dispersion of functionalized graphene sheets in polymer matrix such as polycarbonate [5], poly- urethanes [6] and polystyrene [7] showed enhanced me- chanical and electrical properties. Graphene incorporated polyvinylidene fluoride (PVDF) and polystyrene (PS) nanocomposites have also been studied to obtain desired dielectric permittivity and low percolation threshold [8,9]. * Corresponding author. Tel.: þ91 9894566487. E-mail addresses: varadgm@gmail.com, gm_joshi@rediffmail.com (G. M. Joshi). Contents lists available at ScienceDirect Polymer Testing journal homepage: www.elsevier.com/locate/polytest http://dx.doi.org/10.1016/j.polymertesting.2014.01.015 0142-9418/Ó 2014 Elsevier Ltd. All rights reserved. Polymer Testing 34 (2014) 211–219