Abstract

The stability of sensitive materials is of great importance to humidity sensors. A novel method is used to synthesize cross-linked polymers by a free radical polymerization while introducing the pyridine salt unit with a click reaction by a one-pot reaction. The obtained polymers were used for humidity sensors and the humidity sensitive properties were researched systematically. By introducing polar units to the side chain of the polymer, the humidity sensitive properties were improved greatly. The optimum sensor shows good sensing properties during the whole relative humidity range. In addition, the polymer sensor shows very quick response to humidity, with a response time of 6 s and a recovery time of 17 s. This method is also applicable for developing other functional materials.