Moisture Absorption Effects on the Mechanical Properties of Epoxy Nano Composites

Plastic composite material has been in to frontier of research as one of the new competitive materials in engineering. Especially, fiber reinforced plastic (FRPs) is a relatively new class of composite material manufactured from fibers and resins, and has proven efficient and economical for the development and repair of new and deteriorating structures. In this work, we report the effect of moisture on the mechanical properties of epoxy composites strengthened with MWNTs. Different composition of carbon nanotubes (MWNT) (0.1 -0.2%) were mixed with epoxy matrix by sonication method and castings were prepared by moulding technique. The different mechanical properties were evaluated at room temperature. One set of samples were immersed in distilled water at 50°C for moisture absorption and strength degradation studies. The moisture absorption data on each specimen is tabulated and analyzed for the absorption characteristics. From the moisture absorption curves, maximum moisture content and diffusion coefficients were calculated for all the samples. The wet mechanical properties important for the technological applications were generated including fracture toughness, flexural strength and modulus. Also, the specimens were tested for the degradation studies after the absorption of maximum moisture. In addition to the above investigations, the hardness of the resulting nano composites was also checked. All the studies were carried out to characterize neat resin castings of the resin system under study with and without carbon nano tubes and thus generate some data on various properties as mentioned above. However there is a lot of scope for future work on neat resin castings and as well as at laminate level on these nano composites to optimize these composites for practical aerospace applications especially for the fuselage of the air flights