@article{FangWangWirgesetal.2011,
  author    = {Fang, Peng and Wang, Feipeng and Wirges, Werner and Gerhard, Reimund and Basso, Heitor Cury},
  title     = {Three-layer piezoelectrets from fluorinated ethylene-propylene (FEP) copolymer films},
  series = {Applied physics : A, Materials science \& processing},
  volume    = {103},
  journal   = {Applied physics : A, Materials science \& processing},
  number    = {2},
  publisher = {Springer},
  address   = {New York},
  issn      = {0947-8396},
  doi       = {10.1007/s00339-010-6008-2},
  pages     = {455 -- 461},
  year      = {2011},
  abstract  = {A process for preparing three-layer piezoelectrets from fluorinated ethylene-propylene (FEP) copolymer films is introduced. Samples are made from commercial FEP films by means of laser cutting, laser bonding, electrode evaporation, and high-field poling. The observed dielectric-resonance spectra demonstrate the piezoelectricity of the FEP sandwiches. Piezoelectric d (33) coefficients up to a few hundred pC/N are achieved. Charging at elevated temperatures can increase the thermal stability of the piezoelectrets. Isothermal experiments for approximately 15 min demonstrate that samples charged at 140A degrees C keep their piezoelectric activity up to at least 120A degrees C and retain 70\% of their initial d (33) even at 130A degrees C. Acoustical measurements show a relatively flat frequency response in the range between 300 Hz and 20 kHz.},
  language  = {en}
}