Inkjet and extrusion printing of conducting poly(3,4-ethylenedioxythiophene) tracks on and embedded in biopolymer materials

Abstract

Two printing methods, extrusion and inkjet, are used to deposit tracks of PEDOT/PSS conducting polymer onto biopolymer films with a view to prepare implantable tissue mimics containing electronic devices. Extruded tracks offer lower printing resolution, but better electrical characteristics compared to inkjet printed tracks. The biopolymer–ink interaction results in narrower printed tracks compared to those on glass. This affects the final conductivity, which is lower for printed tracks on biopolymer than for lines printed on glass, due to the part of the track lying below the surface. Extrusion printing is used to embed tracks into a biopolymer matrix, resulting in significant improvement in electrical characteristics. The electrical conductivity of embedded tracks (17 S cm⁻¹) is an order of magnitude higher than for track deposition on the surface of biopolymer film and 3 times higher than for tracks on glass.