Thermoplastic PHB-Reinforced Chitosan Piezoelectric Films for Biodegradable Pressure Sensors

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Science

Background:

• Flexible and wearable pressure sensors are crucial for smart medicine and health monitoring.
• Developing degradable, disposable pressure sensors presents significant fabrication challenges.
• Chitosan (CS) and poly(3-hydroxybutyrate) (PHB) are biocompatible and biodegradable materials with potential for electronic applications.

Purpose of the Study:

• To fabricate and characterize novel piezoelectric films based on chitosan reinforced with poly(3-hydroxybutyrate) for disposable pressure sensors.
• To investigate the effect of PHB doping on the piezoelectric properties and performance of chitosan films.
• To evaluate the biodegradability and potential applications of the developed CS/PHB films in intelligent sensing.

Main Methods:

• Fabrication of chitosan (CS) and poly(3-hydroxybutyrate) (PHB) piezoelectric films using a simple, low-cost, and environmentally friendly roll-forming method.
• Characterization of the piezoelectric properties, including the effective piezoelectric coefficient, of the CS/PHB films.
• Evaluation of the pressure sensor performance, including response sensitivity and linear range, and assessment of the film's biodegradability in a natural soil environment.

Main Results:

• PHB doping significantly increased the effective piezoelectric coefficient of the chitosan-based film by 23% (from 40.12 to 49.38 pm/V).
• The CS/PHB film-based pressure sensor demonstrated excellent response sensitivity (484 mV/kPa) and a wide linear response range (0-130 kPa).
• The CS/PHB film exhibited complete degradation within 18 days in a natural soil environment, highlighting its outstanding biodegradability.

Conclusions:

• Successfully fabricated biodegradable and piezoelectric chitosan-based films with enhanced properties through PHB reinforcement.
• The developed CS/PHB films show great promise for applications in haptic sensors and motion monitoring due to their high sensitivity and rapid response.
• This work promotes the innovation of green chitosan-based electronic devices and disposable pressure sensors, addressing current environmental concerns.