Piezoelectricity of vinylidenefluoride–trifluoroethylene copolymer films in various poling conditions

Piezoelectricity of ferroelectric thin polymer films strongly depends on the poling condition. We can classify them as conventional electrical and novel nonelectrical poling. These experiments show the comparative results on piezoelectricity induced from various poling processes (i.e., electrical corona poling, nonelectrical surface‐energy poling, and a combination of both methods simultaneously in various poling conditions). The most interesting result confirmed that the piezoelectricity increased significantly when the combination poling was applied with appropriate metal substrate and temperature decreasing rate.