Thermoplastic PHB-Reinforced\nChitosan Piezoelectric\nFilms for Biodegradable Pressure Sensors

Flexible\nand wearable pressure sensors have attracted\nsignificant\nattention in the fields of smart medicine and human health monitoring.\nNevertheless, the design and fabrication of degradable disposable\npressure sensors still face urgent challenges. Herein, we fabricated\npoly(3-hydroxybutyrate) (PHB)-reinforced chitosan (CS) piezoelectric\nfilms for intelligent sensors through a simple, low-cost, and environmentally\nfriendly roll-forming method. The results show that PHB doping successfully\nincreased the effective piezoelectric coefficient of the chitosan-based\nfilm from 40.12 to 49.38 pm/V (a 23% increase). Simultaneously, the\npressure sensor based on the CS/PHB film exhibited excellent response\nsensitivity (484 mV/kPa) and a wide linear response range (0–130\nkPa), which could be used as haptic sensors and motion monitoring\nsensors for the fast response to human motion signals. Additionally,\nthe CS/PHB film could be completely degraded within 18 days in a natural\nsoil environment, demonstrating outstanding degradability. Therefore,\nchitosan-based piezoelectric films with excellent biodegradability\nand piezoelectric characteristics have been successfully fabricated\nin this work, which will promote the innovative development of green\nchitosan-based electronic devices and disposable pressure sensors.