TY - JOUR
T1 - Photostimulated discharge in electret polymers
T2 - An alternative approach for investigating deep traps
AU - Mellinger, Axel
AU - González, Francisco Camacho
AU - Gerhard-Multhaupt, Reimund
N1 - Funding Information:
The authors gratefully acknowledge partial support from the PROBRAL program (CAPES/DAAD) and from the European Community within the GROWTH project DURASMART. Our thanks go to L. F. Santos and R. M. Faria (Instituto de Física de São Carlos, Universidade de São Paulo, Brazil) and W. Wirges (Universität Potsdam, Germany) for their experimental support and many stimulating discussions. The cellular PP samples were kindly provided by M. Paajanen of VTT Processes in Tampere, Finland. F.C.G. acknowledges financial support from PROMEP-SUPERA (Mexico).
PY - 2004/4
Y1 - 2004/4
N2 - The stability of space charge in electrets such as polytetrafluoroethylene (PTFE), polyethylene terephthalate (PETP) and polypropylene (PP) under ultraviolet irradiation has been investigated using photostimulated discharge spectroscopy. While only weak discharge currents were observed in PTFE coated with semitransparent gold electrodes, up to 15 pA/cm2 were found in PETP around the UV absorption edge near 310 nm. Space charge profiles obtained with the piezoelectrically generated pressure step method indicate that near-surface charges were almost completely removed. In PP foam, recent findings of a UV-reduced d33 coefficient were confirmed for exposure times of up to 3.5 h, and a discharge peak at 200 nm could be assigned to the charges stored on the surfaces of the voids. The unique morphology and the (quasi-) piezoelectric properties of cellular PP make it a role model for the future investigation of charge storage in electrets.
AB - The stability of space charge in electrets such as polytetrafluoroethylene (PTFE), polyethylene terephthalate (PETP) and polypropylene (PP) under ultraviolet irradiation has been investigated using photostimulated discharge spectroscopy. While only weak discharge currents were observed in PTFE coated with semitransparent gold electrodes, up to 15 pA/cm2 were found in PETP around the UV absorption edge near 310 nm. Space charge profiles obtained with the piezoelectrically generated pressure step method indicate that near-surface charges were almost completely removed. In PP foam, recent findings of a UV-reduced d33 coefficient were confirmed for exposure times of up to 3.5 h, and a discharge peak at 200 nm could be assigned to the charges stored on the surfaces of the voids. The unique morphology and the (quasi-) piezoelectric properties of cellular PP make it a role model for the future investigation of charge storage in electrets.
KW - Electret polymers
KW - Photostimulated discharge
KW - Piezoelectric coefficient
KW - Piezoelectric resonances
KW - Piezoelectricity
KW - Polyethylene terephthalate
KW - Polypropylene
KW - Polytetrafluoroethylene
KW - Thickness extension resonance
KW - UV spectroscopy
KW - Voided polymer
UR - http://www.scopus.com/inward/record.url?scp=2342531230&partnerID=8YFLogxK
U2 - 10.1109/TDEI.2004.1285890
DO - 10.1109/TDEI.2004.1285890
M3 - Article
AN - SCOPUS:2342531230
SN - 1070-9878
VL - 11
SP - 218
EP - 226
JO - IEEE Transactions on Dielectrics and Electrical Insulation
JF - IEEE Transactions on Dielectrics and Electrical Insulation
IS - 2
ER -