Effect of Graphene Oxide Reduction with L-Ascorbic Acid on Electrical Conductivity and Mechanical Properties of Graphene Oxide-Epoxy Nanocomposites

Document Type : Research Article


Department of Chemical Engineering, School of Chemical and Petroleum Engineering, Shiraz University, 71348-51154 Shiraz, I.R. IRAN


In this study, conductive nanocomposites were prepared by dispersing two different types of nanoparticles in the epoxy resin (bisphenol A) matrix. In the first case, Graphene Oxide (GO) was used as the nanoparticle filler, while in the second one, reduced graphene oxide (rGO), which was made using L-ascorbic acid as the reducing agent, was dispersed in the epoxy base. For this purpose, different weight percentages of nanoparticles including 0.25, 0.5, 1, and 2 % were selected to be examined. The prepared samples then were compared with the blank sample in terms of electrical conductivity and mechanical properties involving tensile strength and elastic modulus.  According to FT-IR and XRD analyses, it was observed that oxygen functional groups were reduced substantially for the rGO. However, in this case, owing to the transformation of the binary system from polar-polar to polar-nonpolar, rGO could not disperse well in the epoxy matrix. To address this problem, nonylphenol polyethylene was used as a surfactant to provide more suitable dispersion in the epoxy. Results also demonstrated that the electrical conductivity of rGO-epoxy nanocomposite increased dramatically in comparison with both neat epoxy samples and epoxy/GO ones, and the maximum conductivity of 3×10-4 S/m (8 orders of magnitude higher than the pristine epoxy resin) was achieved at the rGO percentage of 2%. In addition, mechanical properties (e.g. tensile strength and elastic modulus) were superior in the case of GO and rGO nanocomposites in comparison to that of the blank sample, except for the 2 wt% rGO. Therefore, the best-prepared nanocomposite was the 1wt% rGO sample which improved the electrical conductivity up to 7 orders of magnitude. Likewise, tensile strength and elastic modulus modified 21% and 34 %, correspondingly relative to the neat epoxy sample.


Main Subjects

[1] Shirakawa H., Louis E., Macdiarmid A.G., Chiang C.K., Heeger A.j., Synthesis of Electrically Conducting Organic Polymers Halogen Derivatives of Polyacetylene, J. Chem. Soc. Chem. Com. (JCSCC), 474:578-580(1977).
[2] Chiang C.K., Park Y.W., Heeger A.J., Shirakawa H., Louis E.j., Macdiarmid A.J., Conducting polymers: Halogen doped polyacetylene, J. Phys. Chem.(JPC), 69: 5098-5104 (1978).
[4] Liang C., Qiu H., Han Y., Gu H., Song P., Wang L., Kong J., Cao D., Gu J., Mater J., Superior Electromagnetic Interference Shielding 3D Graphene Nanoplatelets/Reduced Graphene Oxide Foam/Epoxy Nanocomposites with High Thermal Conductivity, China. J. Mat. Chem. C.(MKC), 7: 2725-2733 (2019).
[5] Wei J., Inam F., Vo T., Epoxy/Graphene Nanocomposite- Processing and Properties: a Review, UK. Roy. Soc. of. Chem. (RSC), 5: 73510-73524 (2015).
[7] Gado M. A., Sorption of Thorium Using Magnetic Graphene Oxide Polypyrrole Composite Synthesized from Water Hyacinth Roots, Egypt. Iran. J. Chem. Chem. Eng.37(3): 145-160 (2018).
[8] Sharma R., Chadha N., Saini P., Determination of Defect Density, Crystalite Size and Number of Graphene Layers in Graphene Analogs Using X-Ray Diffraction and Raman Spectroscopy, India. Ind. J. Pur. App. Phy., 55: 625-629 (2017).
[9] Ghalmi Y., Sayah A., Bahloul A., Nessark B., Enhancement of the Electrochemical Properties of PbO2 by Incorporation of Graphene ExfoliatedIran. J. Chem. Chem. Eng. (IJCCE), 39(2): 269-274 (2020).
[10] Foroughi F., Rahsepar M., Hadianfard M. J., Kim H., Facile Synthesis and Electrochemical Performance of Graphene-Modified Cu2O Nanocomposite for Use in Enzyme-Free Glucose Biosensor, Iran. J. Chem. Chem. Eng., 39(2): 1-10 (2020).
[11] Balint R., Cassidy N., Cartmell S., Conductive Polymers: Towards A Smart Biomaterial for Tissue Engineering, UK. Act. Bio., 10: 2341-2351 (2014).
[12] Ram M., Yavuz O., CO gas Sensing from Ultrathin Nano-Composite Conducting Polymer Film, USA.Sen. Act. B.(SAB), 106:750–757 (2005).
[13] Adak B., Joshi M., Butola B., Polyurethane/functionalized-graphene Nanocomposite Films with Enhanced Weather Resistance and Gas Barrier Properties, India. Com. Par. B. 176: 107303-107315 (2019).
[14] Ding H., Zhang S., Chen J., Reduction of graphene Oxide at Room Temperature with Vitamin C for RGO–TiO2 Photoanodes in Dye-Sensitized Solar Cell, China.Thi. Sol. Fil. (TSF), 584: 1-8 (2015).
[15] Zhang L., Zhao X., Highly Conductive and Porous Activated Reduced Graphene Oxide Film for High-Power Super Capacitor, USAAme.Che.Soc.(AMS), 12: 1806-1812 (2012).
[16] Gong J., Yang H., Yang P., Investigation on Field Emission Properties of N-Doped Graphene-Carbon Nanotube Composites, China, Com. Par. B.(CPB), 36: 250-255 (2015).
[18] Potts J., Dreyer D., Bielawski C., Ruoff R., Graphene-Based Polymer Nanocomposite, Poly., 52:5-25 (2011).
[19] Rafee M, Rafiee J., Enhanced Mechanical Properties of Nanocomposites at Low Graphene Content, ACS nano, 3: 3884-3890 (2009).
[20] Wu Y., Brahma S., Weng S., Chang C., Huang J., Reduced Graphene Oxide (RGO)-SnOx (x=0,1,2) Nanocomposite as High-Performance Anode Material for Lithium-Ion Batteries, Taiwan., 38: 152889-152897 (2019).
[21] Kim H., Abdala A., Graphene/Polymer Nanocomposites, Mac., 43: 6515-6530 (2010).
[22] Ho K.C., Teow Y.H., Mohammad A.W., Ang W.L., Lee P.H., Development of Graphene Oxide (GO)/Multi-Walled Carbon Nanotubes (MWCNTs) Nanocomposite Conductive Membranes for Electrically Enhanced Fouling Mitigation, J. Mem. Sci. (JMC), 552: 189–201 (2018).
[25] Pei S., Cheng H., The Reduction of Graphene Oxide, Car., 50: 3210-3228 (2012).
[26] Li M., Zhou H., Zhang Y., Liao Y., Zhou H., Effect of Defects on Thermal Conductivity of Graphene/Epoxy Nanocomposites, Car., 130: 295-303 (2018).
[28] Zhixin C., Liu L., Wang X., Poly(Urethane-co-vinyl imidazole)/Graphene Nanocomposites, Pol. Com. (PC) 459-466 (2012).
[29] Chua Ch., Pumera M., Chemical Reduction of Graphene Oxide: A Synthetic Chemistry ViewpointRoy. Soc. Chem. (RSC). 20:20-32 (2013).
[33] Wentzel D., Miller S., Sevostianov H., Dependence of the Electrical Conductivity of Graphene Reinforced Epoxy Resin on the Stress Level, Int. J. Eng. Sci. (IJEC), 120: 63–70 (2017).
[34] Moreno J.M., Sanchez V.Y., Hidalgo R.S., Verdejo R., Manchado M.A., Garcia L.F., Blanco C., Mendez R., Customizing Thermallyreduced Graphene Oxides for Electrically Conductive or Mechanical Reinforced Epoxy Nanocomposites, Eur. Pol. J. (EPG), 93: 1–7 (2017).
[39] Fernandez M., Guardia L., Parades J, Vitamin C Is an Ideal Substitute for Hydrazine in the Reduction of Graphene Oxide Suspensions, J. Phys. Chem. (JPC), 114: 6426-6432 (2010).
[40] Zhang J, Yang H.Reduction of Graphene Oxide via L-Ascorbic Acid, Chem. Com., 46: 1112-1114 (2010).
[42] Pei S., Cheng H.M, The Reduction of Graphene Oxide, Car., 50: 3210-3228 (2012).
[43] Nyambo C., Wang D., Wilkie C.A, Will Layered Double Hydroxides Givennanocomposites with Polar or Non-Polar Polymers, Pol.Adv. Tec. (PAT), 20: 332-340 (2009).
[44] Boumaza M., Khan R., Zahrani S., An Experimental Investigation of the Effects of Nanoparticles on the Mechanical Properties of Epoxy Coating, Thi. Sol. Fil. (TSF), 620:160-164 (2016).
[46] Tang G., Jiang Z., Li X., Zhang H., Hong, S., Electrically Conductive Rubbery Epoxy/Diamine-Functionalizedgraphene Nanocomposites with Improved Mechanical Properties, Com. Par. B. (CPB), 67: 564–570 (2014).
[47] Monti M., Rallini M., Puglia D., Peponi L., Torre L., Morphology and Electrical Properties of Graphene, Com. Par. A. (CPA), 46: 166–172 (2013).
[50] Meger test,