A comparative study of the polymer-nanotube interface through a reactive force field and density functional theory

As nanofabrication techniques progress, systems at the nanoscale find a rapidly increasing number of applications in various areas of technology. A particularly spectacular example of this phenomenon is carbon nanotubes (CNTs), tiny graphene sheets rolled up into single-or multi-walled cylinders. So far, CNTs have been used in diverse applications in device technology, drug delivery, field emission, air and water filtration, and many others. In addition to their unusual electronic properties, CNTs also possess extremely high axial strengths and are often used as strengthening agents in various host materials. In this talk, I will present results from a joint project run in the Aeroscape Engineering and Physics Departments on the reinforcement of polymer matrices by carbon nanotubes. We conduct molecular dynamics (MD) and density functional theory (DFT) calculations to model the interaction between the polyetheretherketone (PEEK) polymer and single-walled CNTs. Our study serves not only to understand the physical properties of this novel interface such as adhesion energies, but also as a test of the REAXFF empirical potential (CHO and LG variants) against DFT studies. Following a brief introduction of the problem, I will first show results from our benchmark studies on the elastic properties of the two components separately, namely PEEK and CNTs. I will then present our finding on the interface, starting with a single polymer on a graphene sheet