Low Cost Sponge Based Piezocapacitive Sensors Using Single Step Leavening Agent Mediated Autolysis Process
Abstract
In recent years, porous or sponge based elastomers have been considered very useful for wearable applications, however, one step, economical and rapid fabrication of large area porous elastomers is still a daunting task. In this pursuit we report a leavening agent mediated fabrication of large area, 3D porous Polydimethylsiloxane (PDMS) via a rapid (20min), cost effective and single step method. The leavening agent used decomposes itself during the leavening process by its inherent autolysis property providing a single step method. Unique feature of highly uniform and robust 3D porous features method facilitate tuning of sensitivity along with obtaining sponges of desired size and shape. The peizocapacitive devices fabricated using these 3D porous PDMS sponge exhibited exceptional sensitivity of 0.756 kPa-1 (in linear region) and 0.0117 kPa-1 (in saturation region). These sensors demonstrated excellent response for small scale as well as for large scale motion sensing applications such as pulse pressure sensing, tactile sensing, touch pad, wrist and palm movements.
