Poly real (vinylidene fluoride), PVDF, mainly refers to the partial fluorine ethylene homopolymer or partial fluorine ethylene and other small amount of fluoride copolymer of vinyl monomer, it combines the characteristics of fluorine resin and general resin, in addition to have good resistance to chemical corrosion resistance, high temperature resistance, oxidation resistance, weather resistance, radiation resistance, also a piezoelectric, dielectric properties, thermoelectricity, such as special performance.