High strength and anti‐freezing piezoresistive pressure sensor based on a composite gel

Abstract

Abstract Piezoresistive sensors constructed by functionalized elastic gel have received broad research by virtue of the visible advantages, such as low‐cost, stability of signal collection, and excellent compress strain. Herein, a new method about improved in situ polymerization of pyrrole monomer coated on polyurethane (PU) sponge was developed, which endowed the sponge with high and homogeneous conductivity. Then, a conductive polypyrrole@polyurethane‐polyacrylamide (PPy@PU‐PAM) composite gel was constructed by filling the PPy@PU sponges with PAM gel. The composite gel showed favorable compression performance attributed to the excellent elasticity of the PAM gel and porosity of the elastic PU sponge. The obtained elastomer exhibited excellent compressibility (869 kPa). Moreover, the addition of glycerin endowed the elastomer with excellent frost resistance and compression resilience at −20°C, which could greatly broaden the application in extreme environments. The piezoresistive sensor established by the composite elastomer can withstand and sense high pressure both at 25 and −20°C. Therefore, the pressure sensor shows potential applications in various fields, such as, health‐care monitoring system, motion signal collection, and robotic control.