IAS-2 Seminar: Monte Carlo Simulations of pH-sensitive polyelectrolyte microgels

Stefanie Schneider

Institute of Physical Chemistry, RWTH Aachen University

Join us in person in Building 04.16, Room 2001

Abstract

For weak polyelectrolytes (PE) as well as for weak polyampholytes (PA), not only the pH-pKA value but also the local electrostatic environment of the ionisable group determines the degree of ionisation and structural properties of the polymer. The proximity of already ionised groups, which is enforced by the interconnectivity of the polymer chain, influences the probability of additional groups becoming ionised. Therefore, the degree of ionisation for polymers with different architectures differs from the ideal value obtained for monomers at low concentrations. Linear PAs have been investigated analytically [1] and in computer simulations [2]. PA with a network topology is interesting because of its possible applications for the pH-triggered uptake and release of guest molecules.

Polyelectrolyte and polyampholyte microgels of different topologies have been investigated using constant pH-Monte Carlo simulations. Ionisation, swelling, as well as the uptake and release of guest molecules, were studied [1-4].

[1] C. Hofzumahaus, P. Hebbeker, S. Schneider, Soft Matter, 2018, 14, 4087.

[2] C. Hofzumahaus, C. Strauch, S. Schneider, Soft Matter, 2021, 17, 6029.

[3] C. Strauch, S. Schneider, Soft Matter, 2023, 19, 938.

[4] C. Strauch, S. Schneider, Soft Matter, 2024, 20, 1263.