The Piezoelectrically-generated pressure-step method (PPS)
The knowledge about polarization or space-charge distribution in charged polar polymers (polyvinylidene fluoride PVDF, piezo- and pyroelectric material) or in non-polar polymers (polytetrafluoroethylene PTFE, TeflonTM, electret material) is of general interest, both for fundamental research and for applications.
b-PVDF
Teflon™
Certain molecular groups act as dipoles and can be oriented in an electric field (permanent polarization).
Certain non-polar polymer materials exhibit excellent charge-storage properties (electret materials).
Depending on the material and the poling or charging conditions we get different polarization or charge profiles:
electrode poling
corona charging
room temperature
200°C
The PPS method allows for direct determination of polarization or charge profiles in the thickness direction of thin (10-100 µm) dielectrics.
How does the PPS method work? Continue on the next page...