From force-reporting to force-resistant: using mechanochemistry to understand polymer materials

PD Dr. Robert Göstl, DWI – Leibniz Institute for Interactive Materials, Aachen, Germany
and RWTH Aachen University, Germany

One of the grand scientific challenges of our time is how the remarkable properties of matter emerge from the complex correlations of their molecular constituents. We perform research adhering to this principle by following the results of mechanical stress and strain on macromolecular materials, which often requires to survey large samples with molecular level resolution due to the multiscale nature of force.

To do so, we firstly design and synthesize molecular optical force probes and the respective macromolecular materials made from them in a transdisciplinary approach.^[1] We mainly employ Diels-Alder adducts of π-extended anthracenes and maleimides reporting over covalent bond scission events due to their sensitive nature and facile tunability of their optical properties.^[2,3]

Secondly, we use these mechanofluorophores to investigate the mechanical behavior of complex and non-uniform high-performance polymers, such as rubbers and composites, and soft matter, e.g., hydrogels and colloidal hydrogel networks, in detail developing novel methodologies. From these experiments, we aim to draw conclusions over the behavior of these materials under force.^[4,5]

Eventually, we strive to use the insights gained from this to develop materials with improved mechanical properties by, e.g., introducing pathways to dissipate stresses at the locations where they are most critical or to self-reinforce or by the activation of latent functional motifs to perform mechanically activated chemical reactions.^[6]

References
[1] S. He, M. Stratigaki, S. P. Centeno, A. Dreuw, R. Göstl, Chem. Eur. J. 2021, 27, 15889–15897.
[2] D. Yildiz, C. Baumann, A. Mikosch, A. J. C. Kuehne, A. Herrmann, R. Göstl, Angew. Chem. Int. Ed. 2019, 58, 12919–12923.
[3] C. Baumann, M. Stratigaki, S. P. Centeno, R. Göstl, Angew. Chem. Int. Ed. 2021, 60, 13287–13293.
[4] E. Izak-Nau, S. Braun, A. Pich, R. Göstl, Adv. Sci. 2022, 9, 2104004.
[5] S. He, S. Schog, Y. Chen, Y. Ji, S. Panitz, W. Richtering, R. Göstl, Adv. Mater. 2023, 35, 2305845.
[6] D. Campagna, R. Göstl, Angew. Chem. Int. Ed. 2022, 61, e202207557.