Piezoelectric Thin Polymer Film and Nanofiber Web Based Sensors Applicable to Smart Textiles for Monitoring Vital Signals and Evaluating Energy Expenditure

Widely-used sensors for monitoring vital signals in smart textile were made by rigid semiconductors. So, in this study, physiological sensing belt (PSB) was fabricated by embedding silicone rubber/carbon black/conductive carbon layer coated polyvinylidene fluoride (PVDF) film between elastic bands for monitoring respiration and the movement of thigh muscles. Furthermore, an ECG sensor was designed using electroless silver-plated PVDF electrospunnanofiber web as a potential replacement of the conductive Ag/AgCl gel electrode. We also prepared PVDF and thermoplastic polyurethane (TPU) electrospunnanofiber web for use as capacitive-type nanogenerator/pressure sensor and piezocapacitive sensor, respectively. The TPU based sensor was used as a smart insole material capable of measuring walking pattern and body weight by foot pressure. The above studies gave ample evidence on the suitability of using organic polymer/fabric based-sensors attached to smart textilesfor measuring various types of vital body signals, thereby resulting in management of our personal health.