Conference Presentation (Invited)

FZJ-2022-04920

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Deswelling, thermodynamics, structure, and dynamics in ionic microgel suspensions

Naegele, G. (Corresponding author)FZJ*

2022

Abstract: Suspensions of ionic microgels are of fundamental and technological interest, owing to the sensitivity of the microgel sizes to external control parameters such as concentration, ionic strength and temperature. In this talk, I report on a theoretical study of crowding effects on thermodynamic, structural, and dynamic properties of concentrated suspensions of ionic microgels, which gives new insights into microgel deswelling effects.Methods for calculating the crowding-dependent microgel radius are discussed, used for the calculations of an effective microgel pair potential from which thermodynamic, structural and dynamic suspension properties are determined. It is shown that deswelling mildly enhances self- and collective diffusion and the osmotic pressure, lowers the suspension viscosity, and significantly shifts the suspension crystallization point to higher concentrations. In a nutshell, a versatile bottom-up approach for computing suspension properties of crowded ionic microgels is presented based on the characteristics of single microgels. If time suffices, I will also discuss pros and cons of different colloidal charge-renormalization methods based on the Primitive Model and Poisson-Boltzmann spherical cell models, and the possible occurrence of an effective colloid charge larger than the bare one.

Keyword(s): Polymers, Soft Nano Particles and Proteins (1st) ; Soft Condensed Matter (2nd)

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Contributing Institute(s):

1. Biomakromolekulare Systeme und Prozesse (IBI-4)

Research Program(s):

1. 5244 - Information Processing in Neuronal Networks (POF4-524) (POF4-524)

Appears in the scientific report 2022

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