Project Details
Untersuchung von molekularen mechanochromen Federn: von der Spannungsübertragung in Einzelmolekülen zu Spannungsrelaxation und Alterung in Polymeren
Applicants
Professor Dr. Günter Reiter; Professor Dr. Michael Sommer; Privatdozent Dr. Michael Walter
Subject Area
Polymer Materials
Experimental and Theoretical Physics of Polymers
Preparatory and Physical Chemistry of Polymers
Experimental and Theoretical Physics of Polymers
Preparatory and Physical Chemistry of Polymers
Term
since 2018
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 412095266
This proposal is concerned with the design and implementation of new donor-acceptor-donor (DAD) torsional springs for force sensing to probe ageing in polymeric materials. We merge together tailored mechanochromic materials (Sommer), theoretical descriptions of force-induced conformational changes (Walter) and experimental investigations of ageing in different polymers (Reiter). To bring this concept closer to applications, we make bold steps in each of the three areas. Sommer will develop new diketopyrrolopyrrole- and quinoxaline-based DAD springs that exhibit improved optical properties (wavelength region and photoluminescence shift), increased force range and varying reversibility behavior. The DAD springs will also be linked to break points for internal calibration, and finally be covalently incorporated into various matrix polymers. Walter will describe these springs as well as their force-induced deformation theoretically to pre-screen promising candidates. Reiter will perform various time- and temperature-dependent mechanical experiments on films and bulk samples with in-situ photoluminescence monitoring. Walter will finally unfold experimental PL data to derive force-distributions of macroscopic samples as a complement to the theoretical force response of a single chain. Results from this joint proposal will advance utility and diversity of mechanochromic polymers significantly beyond the state-of-the-art. Possible outcome ranges from the availability of molecular springs for broad force range and thus diverse application scenarios to an increased fundamental understanding of how spatio-temporal molecular processes in polymers cause ageing processes. Finally, the concept may be extended to novel multi-functional materials with e.g. strain-modulated electronic properties in the future.
DFG Programme
Research Grants