Flexible Piezoresistive Pressure Sensor Using Wrinkled Carbon Nanotube Thin Films for Human Physiological Signals

• DOI: 10.1002/admt.201700158
• Publication Date: 2017-11-13T11:32:54Z
• Authors: Sun‐Jun Park; Joshua Kim; Michael Chu; Michelle Khine
• Keywords: Piezoresistive effect; Shape-memory polymer; Elasticity; Flexible Electronics

Abstract Highly sensitive and flexible components are essential for applications in wearable electronics. Using low‐cost rapid prototyping methods, piezoresistive pressure sensors fabricated using shrink‐film, a shape memory polymer that retracts upon heat, to introduce wrinkling carbon nanotube thin films, which improves both elasticity sensitivity. The wrinkles not only provide strain relief, but it also sensitivity by 12 800 fold with response time of less than 20 ms. improved is due the surface roughness wrinkles. When two wrinkled electrodes coupled together, number electrical contact points changes actuation thereby changing resistivity. This study then demonstrates applications, such as pulsatile blood flow monitoring voice detection these sensors.