Tannic acid based hyperbranched epoxy/reduced graphene oxide nanocomposites as surface coating materials

Hyperbranched epoxy resin (TAE) was synthesized by a simple polycondensation reaction using biobased tannic acid as a branch generating moiety. The nanocomposites of TAE with different doses (0.25, 0.5, and 1 wt.%) of reduced graphene oxide (RGO) were prepared by solution technique. TAE was cured with poly (amido-amine) hardener at a temperature of 100 degrees C followed by post curing at 120 degrees C. MR, H-1 NMR, C-13 NMR etc. studies support the hyperbranched structure of the synthesized epoxy resin. Transmission electron microscopy (TEM), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and UV-vis spectroscopic analysis confirmed the formation of polymer nanocomposites. The results of performance studies showed that polymer nanocomposites exhibited better performance than the pristine polymer. The tensile strength, scratch hardness, impact strength, initial degradation temperature and gloss were all improved by the formation of nanocomposite. Thus results indicate the studied nanocomposite has the potential for use as a surface coating material. (C) 2016 Elsevier B.V. All rights reserved.