Implementation of hybrid PDMS-graphite/Ag conductive material for flexible electronic devices and microfluidic applications

Flexible electronic materials have received intensive attentions in diverse applications owing to unprecedented advantages such as good flexibility, low cost, multifunctionality and disposability, while not undermining its electronic performance. In this paper, conductive material consisting of polydimethylsiloxane (PDMS) and conductive inks (graphite or Ag) is used, which not only keeps the conductivity of the ink, but also improves the hydrophobicity of the PDMS and adhesiveness of the conductive ink. To further facilitate the implementation of the material in diverse applications, two types of novel fabrication methods termed plastic film mask printing (PFMP) and wire-cut electrical discharge cutting (WEDC) were proposed and presented, leveraging future usage in regards to requirements like ease of operation, low-cost and high-resolution. In addition, 2D/3D paper-based flexible circuits, supercapacitors and 3D PDMS-based conductive model were applied to further provide demonstrative applications of the material, along with dielectrophoretic (DEP) separation of the plasma from the whole human blood on paper and polystyrene (PS) microspheres from the solution on paper- and PDMS-based devices respectively. We believe the proposed conductive materials and fabrication methods meet the state-of-art scientific research needs and will provide a new direction for future flexible electronics, lab-on-a-chip (LOC) and biomedical fields.