The Elongation Performance of Spirulina-templated Silver Micro Springs Embedded in the Polydimethylsiloxane

Helical conductive particles have attracted much attention in preparing stretchable conductive materials because of their structural flexibility and uniform strain distribution under deformation. In this paper, Spirulina-templated silver micro springs were fabricated using electroless deposition of silver onto Spirulina surface. To investigate their potential application as conductive fillers for stretchable materials, they were mixed into polydimethylsiloxane (PDMS) uniformly, and then the mixture was spin coated on a polyfluortetraethylene (PTFE) plate to form a thin film, during which, micro springs tended to align its major axis along the radial direction of the plate. The tensile tests of micro springs were carried out using the film along the alignment direction of micro springs on the custom-made setup. Under the optimal condition of coating thickness of 0.67 mu m, helical pitch of 29 mu m and annealing temperature of 300 degrees C, the average elongation of micro springs can reach up to similar to 106.9%, which indicates that the as-prepared Spirulina-templated silver micro springs are promising flexible conductive fillers for fabricating stretchable conductive materials.