Using theory and simulation, our overall goal is to design lightweight composites that exhibit optimal electrical conductivity and mechanical integrity. These characteristics are vital in the fabrication of portable and durable electronic devices. The materials to be examined consist of organic polymers and inorganic nanoparticles. The resulting nanocomposites integrate the flexibility and processability of the polymers and the electromagnetic properties of the particles. We specifically focus on mixtures that involve blends of different polymers, as well as the nanoparticles. In these systems, we can exploit the polymer-polymer, polymer-particle and particle-particle interactions to manipulate the structure of the material. In particular, our aim is to harness these interactions to drive the nanoparticles to form percolating structures at very low volume fractions. Such percolating networks not only allow current to flow through the material, but also reinforce the polymeric matrix. A reduction in the percolation threshold results in both weight and cost reductions.
It is anticipated that the findings will allow us to establish fundamental correlations between the nanoscopic structures of the components, the mesoscopic morphology of the mixture, and the macroscopic electrical/mechanical properties of the material. The studies will also elucidate how processing affects both the morphology and macroscopic properties. By engaging in these research activities, the students and post-doctoral fellows involved in the project will obtain a background and training in nanotechnology. This expertise will make them better qualified to meet the demand within industry, national labs and academics. The Approaches to Combat Terrorism Program in the Directorate for Mathematics and Physical Sciences supports new concepts in basic research and workforce development with the potential to contribute to national security. In particular, the findings will facilitate the development of flexible, lightweight and high energy density nanocomposites, which can be utilized in fabricating portable electronic and photonic devices.
