Nanocomposites and nanomaterials

Determination of tensile and impact properties of graphene nanoplatelet/epoxy nanocomposite
Sepet H.1 and Tarakcioglu N.1
1Department of Metallurgy and Materials Engineering, Faculty of Technology, University of Selçuk, Konya-42130, Turkey. 
E-mail:harunsepet@selcuk.edu.tr

The graphene, which was discovered in 2004 by Andre Geim and Konstantin Novoselov, has been the subject of research by scientists since this date [1, 2]. Improving the mechanical properties of epoxy resin is only one of these issues [3, 4].
The aim of this study is to investigate the effect of graphene nanoplatelets (GnPs) reinforcement ratio on tensile and impact properties of epoxy resin and, to determine optimum ratio of GnPs reinforcement in terms of both tensile and impact properties. The GnPs reinforcement ratio detected will be used in the production of GnPs reinforced filament winding composite pressure vessels.
0.0%, 0.125%, 0.25%, 0.5%, 0.75% and 1.0 %wt. GnPs and epoxy resin were mixed in a beaker for 30 minutes by using an ultrasonic mixer. The beaker was cooled to prevent overheating during mixing. Then, hardener in 100:80 ratio was added to the mixtures. Tensile and impact test samples were cured at 120 °C for 3 hours and then, post-cured at 140 °C for 3 hours.
The tensile and impact properties of GnPs/epoxy test samples were determined according to ASTM D638 and ISO 179, respectively.
As a result, it was found that 0.25 %wt. GnPs increased ultimate tensile strength, the modulus of elasticity and % strain of the epoxy matrix the by 11.9%, 6.2% and 19.5%, respectively. A tendency to decrease in tensile properties of samples was determined due to GnPs agglomeration detected in 0.5%, 0.75% and 1.0 %wt. GnPs reinforced epoxy samples. It was found that the impact strength of the samples increased regularly as the GnPs reinforcement rate increases. The tensile properties of the samples were determinative in the detection of the GnPs reinforcement ratio.
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