Pressure-Induced Coil to Globule Transition in Poly-Sulfobetaine Polymer Systems: Towards Tailored Antifouling Coatings

• Applicant: Professor Dr. Emanuel Schneck
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry ; Experimental and Theoretical Physics of Polymers
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 545656780

The temperature-induced coil to globule transition of polymers with a lower critical solution temperature (LCST) has been widely exploited for the design of responsive materials and surface functionalisations. Within a certain temperature range, the transition can also be induced by pressure variations. In contrast, the pressure and temperature response of polymers with an upper critical solution temperature (UCST) has remained vastly unexplored, even though their pressure response can be expected to be more pronounced in some cases because of high excess volumes associated with the transition. A strong pressure response would make these UCST polymers promising candidates for tunable materials and surface coatings, notably with regard to antifouling applications or pressure-based cleaning procedures. Here, we propose a comprehensive thermodynamic and structural characterization of the pressure and temperature response of UCST-type poly(sulfobetaine) polymers in solution and as polymer brushes terminally grafted to solid surfaces. For this purpose, we will combine scattering techniques with x-rays and neutrons with complementary experimental techniques, atomistic molecular dynamics (MD) simulations, and thermodynamic modeling. In parallel, we will investigate the influence of pressure and temperature on the antifouling effect of the polymer brushes quantified in terms of the surface-adsorption of proteins as well as their triggered desorption. This project is built upon the highly complementary research profiles of Leonardo Chiappisi (L.C.) and Emanuel Schneck (E.S.). It leverages the expertise of L.C. in the characterization of polymer systems and their response to pressure changes, as well as the competences of E.S. in the characterization of complex coatings and their interaction with biomacromolecules. Additionally, the project fosters collaboration between two researchers with different backgrounds: chemistry for L.C. and physics for E.S., highlighting the interdisciplinary nature of the project. Finally, this project represents an opportunity to train the next generation of scientists in neutron scattering techniques, which will be of essential importance to fully exploit the potential of the German and European neutron sources in the near future.

• DFG Programme: Research Grants
• International Connection: France
• Partner Organisation: Agence Nationale de la Recherche / The French National Research Agency
• Cooperation Partner: Dr. Leonardo Chiappisi