Glass fiber/Carbon nanotube/Epoxy hybrid composites: Achieving superior mechanical properties

Abstract

Owing to their excellent physical and mechanical properties, polymer-matrix hybrid nanocomposites have found extensive applications in various fields. In this study, different parameters such as materials characteristics and processing parameters are investigated and optimally selected for composite fabrication. The purpose of selecting the optimal parameters and fabricating different types of composite samples was to achieve simultaneous and high improvement in various mechanical properties of epoxy resin. As a result, the process of this study was designed in such a way that by making epoxy-matrix composites reinforced with carbon nanotubes (CNTs) in different CNT weight percentages (0.1, 0.5, and 1 wt%) via solution casting method and using optimal values for material characteristics and processing parameters, the improvement of epoxy mechanical properties for each CNT weight percentage was investigated. Results indicated that the highest improvement in mechanical properties of CNT/epoxy composite was observed in 0.5 wt% CNT sample which had a tensile strength of 61 MPa and Young's modulus of 1.8 GPa. Then, CNT/epoxy composites with the highest improvement in mechanical properties were selected to fabricate the matrix phase of glass fiber/CNT/epoxy hybrid composite. Hybrid composite samples with fiber to matrix ratio of 45:55 were fabricated via the hand lay-up technique. To achieve maximum improvement of mechanical properties for the hybrid composite, the optimal parameters were selected which led to the maximum tensile strength of 300 MPa and Young's modulus of 24.9 GPa. Mechanical properties of the glass fiber/CNT/epoxy hybrid composites showed an identical trend to the CNT/epoxy composite. Moreover, all the fracture mechanisms of CNT/epoxy and glass fiber/CNT/epoxy composites were precisely investigated by scanning electron microscopy.