Efficient preparation of PDMS-based conductive composites using self-designed automatic equipment and an application example

In this paper, the fabrication process of poly-dimethylsiloxane (PDMS)-based microstructured conductive composites via differential temperature hot embossing was proposed based on the spatial confining forced network assembly theory. The mold temperature was kept constant throughout the whole embossing cycle in this method, whereas the setting temperatures of the upper and lower molds were different. To solve the problem of poor conveying performance, a double-station automatic hot embossing equipment was designed and developed. A "bullet-filled" accurate feeding system was designed aiming at the high viscosity and feeding difficulty of blended PDMS-based composites before curing. Dispersion mold and semifixed compression mold were designed according to different functional requirements of different workstations. The developed automatic hot embossing equipment had already been successfully applied to the continuous preparation of conductive composites with greatly improved processing precision and efficiency. Furthermore, the conductive composites with and without microstructures can be used as flexible sensors for pressure measurements.