(209a) Photophysical, Electrical and Dosy NMR Characterization of 2D Polyaramid Systems

Polymers that extend covalently in two dimensions have attracted recent attention as a means of combining the mechanical strength and in-plane energy conduction of conventional two-dimensional (2D) materials with the low densities, synthetic processability and organic composition of their one-dimensional counterparts. This work will present the synthesis and characterization of a 2D polyaramid system based on a homogenous 2D irreversible polycondensation resulting in a covalently bonded 2D polymeric material that is chemically stable and highly processable. This work investigates the time evolution of molecular weight of such systems during synthesis using diffusion-based NMR (DOSY NMR). Further processing yields highly oriented, free-standing thin films with unique photonic and photophysical properties. Spin-coated films will fluoresce differently when excited perpendicular (isotropic) or parallel (anisotropic) to the film surface and platelet orientation. Measurements indicate that such 2D polyaramid films exhibit anisotropic electrical conduction. These combined characterization approaches enrich the picture of 2D polyaramid systems and elucidate their unique combinations of properties.