Effect of repeated hydrothermal cycling on the durability of glass fiber/epoxy composites with and without carbon nanotube reinforcement

Enhancing the performance of polymeric composites by incorporating carbon nanotube (CNT) is a current research trend. In this article, the performance of glass fiber reinforced epoxy (GE) composite with and without CNT has been observed under repeated hydrothermal cycling (HC) between 15 and 50 degrees C water baths. Before carrying out the HC, the optimum concentration of CNT in the GE composite was obtained by flexural test. This study first confirms that the addition of 0.1 wt% of CNTs resulted in a 6.68% and 6.47% increment in flexural strength and modulus compared to neat GE composite. Alteration in the performance of the neat GE and 0.1 wt% CNT-GE was then analyzed after performing HC for 20, 40, and 60 cycles by conducting mechanical (flexural), thermomechanical (dynamic mechanical thermal analysis [DMA]), chemical (Fourier transform infrared spectroscopy [FTIR]) and fractographic (scanning electron microscopy [SEM]) analysis. Degradation in the mechanical performance of the CNT embedded GE composite was found to be faster than the neat one with the increasing number of HC. The possible reason has been explained based on the evidence obtained from DMA, FTIR, and SEM analysis.