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Since PVDF was developed by Japanese scientists in 1970S, few countries could manufacture the novel piezoelectric polymer films so far. Currently, when used as the electronic units, more and more defects from the PVDF films were exposed. For example, it is difficult to obtain the full or large thickness of 1mm piezoelectric films because of its low rate of finished products, which lead to the raise of the film price result from a plenty of wastes of the raw PVDF material. Moreover, some feedback from the customers has pointed the low stability of PVDF film. The piezoelectric sign was often weakened as service time increased because the film was stretched with the relaxor or intense stress frequently.
In 2010, by means of many experiments, a novel P(VDF-TrFE) piezoelectric thick film were synthesized by Zhicheng Zhang group at Xi'an Jiaotong University which possesses a unique dielectric, piezoelectric, and pyroelectric properties. comparing to traditional ceramics piezoelectric materials, P(VDF-TrFE) possesses the wide frequency response band, large dynamic range, high stress-electric transfer sensitivity, powerful mechanical intensity, and well acoustic impedance matching properties. In addition, for its low density, soft texture, good stress, water, and chemical resistances properties, the copolymer film could be easily processed into slice and pipe with different shapes and area. Therefore, it is often used in the following fields such as mechanics, acoustics, optics, electronic, measurement, infrared detector, safeguarding, medical care, military affairs, transportation, information engineering, office automation, ocean development, and geological exploration. P(VDF-TrFE) films with the thickness is
