3D Printing of Conducting Polymers

3D printing can bring exciting new opportunities to the field of organic electronics by defying the current 2D form factor, creating electronics that conform to the body contour of each unique individual, and realizing electronics that can fit in irregularly-shaped void spaces. Direct ink write (DIW) is the most versatile 3D printing method for conjugated polymers due to their solution processability. However, current DIW-printed conjugated polymers suffer from inferior electrical properties (e.g. conductivity one order of magnitude lower than spin-coated counterparts) because of their sensitivity to processing conditions. Here, we elucidate the effect of this new processing method on the fundamental structure-property relationships of a benchmark conducting polymer, PEDOT:PSS. New insights from these studies subsequently guide us to create tailored material formulation and processing conditions for this extrusion printing mechanism, which led to PEDOT:PSS conductivity comparable to their conventionally 2D processed thin films. Finally, we demonstrate 3D freeform electronics and functional prosthetics using multi-material DIW printing of PEDOT:PSS and materials with different electrical and mechanical properties.