Synchronous monitoring of underwater dynamic/static pressure based on piezoelectric/capacitive polyester elastomer/carbon nanotube composites

Abstract

Pressure sensors provide significant information for monitoring and exploration of complex underwater environments. Current sensing technology of underwater pressure has certain limitations in the integration of individual sensors and decoupling of dynamic and static mechanical signals. In this paper, a polyester-based piezoelectric elastomer was synthesized and blended with modified nanocarbon fiber (DPBPE) to prepare a piezoelectric/capacitive composite, achieving integrated and synchronous identification of dynamic and static pressures. The incorporation of modified nanocarbon fiber into the piezoelectric elastomer ensures the piezoelectric and capacitive response of the composites and improves the relative capacitance change rate by 1.6 times compared to that of the neat elastomer. The prepared sensor shows a high sensitivity of 0.8 mV N⁻¹ and 3.09 × 10⁻² kPa⁻¹ for dynamic and static pressure monitoring, respectively. Furthermore, the sensor showed good feedback for changes in water depth and underwater vibration without any mutual interference, indicating its great potential in fields such as ocean waves and underwater pressure monitoring.