An attempt at ultrasonic resonator with piezoelectric polymer film

Abstract

An ultrasonic resonator equipped with the piezoelectric polymer film was constructed for the measurement of velocity and absorption in liquids. The pair of transducers composing the resonator cavity was made of PVDF sheet, 30μm thick, which was coated by aluminum electrode on both surfaces. Some preliminary experiments were made in ethanol as a standard liquid at 25°C over the frequency range from 100 kHz to 2 MHz to examine performance of the resonator and also to determine the instrumental cavity loss. The results suggested that the PVDF can make an almost ideal transducer for the ultrasonic resonator method after some minor technical problems are solved.