Regensburg 2025 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 15: Poster Session I
CPP 15.34: Poster
Monday, March 17, 2025, 19:00–21:00, P4
Dynamic Polarization and Electrostriction of PVDF-Based Copolymer Films as Measured with Double-Modulated Interferometry — Marvin Malchau1, Philipp Ramming2, and •Lothar Kador1 — 1University of Bayreuth, Institute of Physics and BIMF, 95440 Bayreuth, Germany — 2University of Bayreuth, Experimental Physics II, 95440 Bayreuth, Germany
Thin films of a ferroelectric copolymer based on polyvinylidene fluoride (PVDF) were exposed to electric ac fields with amplitudes up to 115 MV/m and frequencies between 5 and 100 Hz. The electrical polarization of the material was calculated by integrating the current flow, and the electric-field-induced thickness change (electrostriction) was measured with double-modulated interferometry. Thickness changes up to 60 nm were observed in an 8 µm thick film. The polarization shows a hysteresis loop typical for ferroelectric materials; it is independent of frequency in the investigated frequency range. The electrostriction exhibits a different type of hysteresis with strong frequency dependence. This indicates that the mechanical relaxation of the polymer film is independent of the electric dipole orientation.
Keywords: ferroelectricity; PVDF; electrostriction; interferometry; double modulation