Interlaminar shear strength of glass fiber reinforced epoxy composites enhanced with multi-walled carbon nanotubes

In this study, we examine the interlaminar shear strength (ILSS) of traditional glass fiber reinforced epoxy composites enhanced by strategically injecting multi-walled carbon nanotube (MWNT)–epoxy suspensions into stationary glass fiber mats. The suspensions were prepared by combining the techniques of high-speed mechanical stirring, ultrasonic agitation and acid oxidation. Two types of process designs were introduced to fabricate the hybrid MWNT/glass/epoxy composites and their relative merits were discussed. Short beam shear (SBS) and compression shear tests (CST) were conducted on the manufactured components to characterize the influence of the process and the weight percentage of nanotubes on the ILSS. The results show that the introduction of MWNT into the composite increased the ILSS by up to 33%. The preferential orientation of the MWNTs in the thickness direction was found to contribute to the increase in the interlaminar shear properties.