Development of a piezo-cantilever transducer and measuring method for evaluation of a temperature-sensitive polymer gel membrane

This paper is concerned with the development of a cantilever transducer patched with a piezoelectric element for evaluating the characteristics of a temperature-sensitive polymer gel membrane. The transducer consists of an aluminum cantilever beam patched with a piezoelectric ceramic and a probe coated by a polymer gel membrane. The probe can be easily attached to the cantilever transducer with double-sided sticky tape. The piezo-cantilever transducer is first simulated with the aid of a finite element method and the relation between the natural frequency change of the transducer and the absorbed mass on the polymer gel membrane is obtained theoretically. For measuring the temperature characteristics of the polymer gel membrane, the experiments are conducted in liquid and out of liquid. The temperature-sensitive poly(N-isopropylacrylamide) gel membrane hydrophilic–hydrophobic characteristics can be explained clearly by the results. Furthermore, two kinds of membrane coating method were proposed. The results indicate that the coating gel membrane has a better effect than the pasted gel membrane. The results also show that the piezo-cantilever transducer has a potential application for detecting polymer gel membrane characteristics conveniently and accurately.