Morphology and electret behaviour of microcellular high glass temperature films
- 193 Downloads
Here we report the processing of cellular, high-temperature polymers for electret applications based on polyetherimide (PEI) and polyetheretherketone (PEEK). The two approaches were utilized to improve the electret properties by insertion of cavities are the physical batch foaming process using carbon dioxide as the blowing agent and the stretching of polymeric plates containing suitable particles, which allows the manufacturing of porous films. The electret properties of foamed PEI and PEEK as well as stretched PEI containing NA11 particles are characterized by isothermal charge decay measurements at 90 °C after corona charging to surface potentials of about 400 V. Investigation of the cellular morphologies was achieved by scanning electron microscopy (SEM) and micro-computertomography (μCT). As result, the cellular films show a clear improved charge storage behaviour compared to the compact films. The best results were achieved with porous PEI films, prepared by stretching and after twofold charging.
KeywordsFoam Surface Potential Draw Ratio Charge Storage Polyetheretherketone
Unable to display preview. Download preview PDF.
- 1.G.M. Sessler, Electrets, 3rd edn., (Morgan Hill, Laplacian Press, 1999) p. 1Google Scholar
- 6.S.C. Chen, L. Huang, P. Hsu, 62nd Annual Technical Conference-Society of Plastics Engineers 1, 434 (2004)Google Scholar
- 10.N. Behrendt, V. Altstädt, H.-W. Schmidt, X. Zhang, G.M. Sessler, IEEE Trans. Dielectr. Electric Insul. (2006), unpublishedGoogle Scholar
- 19.G.M. Sessler, J. Hillenbrand, 10th Int. Symp. Electr. 261 (1999)Google Scholar
- 26.Data sheets of Lipp Terler and Du PontGoogle Scholar