Processing parameters and their influence on mechanical properties of polymeric nanocomposites reinforced with chemically functionalizaed helical carbon nanotubes using nitric acid

Abstract

This research attempted to develop a relationship between the parameters governing the covalent functionalization process and their effects on epoxy matrix polymeric nano-composites. Functionalization with a nitric acid refluxing process was conducted on helical carbon nanotubes (HCNTs). The temperature, acid molarity, and reaction time were all varied during the functionalization process. These functionalized helical carbon nanotubes were then incorporated into epoxy matrix at increasing percent mass 0.02wt%, 0.04wt% and 0.06wt%. Subsequently mechanical properties of the nanocomposite samples were tested in accordance to the ASTM D638-10. A large quantity of data was collected and organized in order to observe the relationship between the effects of functionalization parameters on the HCNT nano reinforcement and the resulting polymer matrix nanocomposites. Along with the large quantity of data the highest improvements for mechanical properties for nanocomposites samples that were reinforced with HCNTs functionalized at 60°C and 100°C, with 8 Molar nitric acid and24hrs of reflux time. Observations with respect to the control samples revealed maximum improvements of 5%, 73%, 18%, and 12% for tensile strength, fracture toughness, Young's modulus, and Percent elongation at failure respectively.