Characterization of Highly Loaded Nanocomposites

Since the advent of production-grade methods for producing single-walled (SWCNT) and multi-walled carbon nanotubes (MWCNT), research has been conducted to utilize the extraordinary properties of these nanoscale cylindrical fullerenes. Tensile strength of an individual MWCNT has been observed as high as 63 GPa with Young’s Modulus approaching ~1 TPa. While nanocomposites may never achieve a tensile of the individual tubes, carbon nanotubes (CNT) are being used as composite fibers in polymers to improve the mechanical (as well as thermal and electrical) properties of the bulk product. Despite the extraordinary mechanical properties of CNTs, only limited improvements in mechanical strength have been demonstrated. Furthermore, these improvements are commonly associated with very low concentrations of CNTs (<1.0% wt.). Attempts in loading the polymer matrix beyond 5% wt. have resulted in failure of the resin to cure or inhomogeneous regions within the nanocomposite resulting in a loss of material strength. In addition, characterization of CNT dispersal within composites beyond bulk property measurements is generally lacking in open literature. For this STTR program, Mainstream Engineering will partner with the Universities Space Research Association to develop an innovative approach for uniformly dispersing CNTs within a polymer matrix and fully characterize the composite using optical microscopy.