Joint Project Proposal on: Development, Characterization, and Applications of Cellular Fluoropolymer Films with Ferroelectret Properties Subproject on: Application-related Properties and Applications of Cellular Ferroelectrets

• Applicant: Professor Dr. Gerhard M. Sessler
• Subject Area: Experimental and Theoretical Physics of Polymers
• Term: from 2005 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5447325

This joint project of the Universities of Erlangen, Potsdam, Darmstadt, and Linz (the latter as a foreign partner) is concerned with the development, characterization and application of charged fluoropolymer films with cellular structure. The geometry of this voided structure and its elastic properties will be designed such that the films are optimal for use as ferroelectrets, i.e. as materials with high piezoelectric coefficients. The Darmstadt subproject relates first to the optimization of the cellular structure, in particular to suitable pressure expansion and charging such that good application-related properties are achieved. The processing and measuring steps will be first performed an the already available cellular polypropylene and later, as soon as available from Erlangen, an the cellular fluoropolymers. The second task of the Darmstadt Laboratory is the design and implementation of a series of applications for which these materials are particularly suited in the sense that the resultant devices are simpler and/or better than existing devices. Among these are piezoelectric microphones, both single film and stacked-film, with omnidirectional and directional charactestics, ultrasonic transmitters, parametric arrays, and headphones. These transducers will be initially designed with the optimized cellular PP films. As soon as suitable cellular fluoropolymer films are available, these will be incorporated into the systems.

• DFG Programme: Research Grants
• International Connection: Austria
• Participating Person: Professor Dr. Siegfried Bauer (†)