This title appears in the Scientific Report :
2020
Deswelling effect on structural and dynamic properties of ionic microgel suspensions
Deswelling effect on structural and dynamic properties of ionic microgel suspensions
Microgels are solvent-containing, cross-linked polymer networks of colloidal size that can reversibly swell or deswell in response to external stimuli. Ionic microgels, in particular, are highly sensitive to changes in environmental conditions such as temperature, solvent quality, polymer cross-link...
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Personal Name(s): | Brito, Mariano (Corresponding author) |
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Contributing Institute: |
Biomakromolekulare Systeme und Prozesse; IBI-4 |
Imprint: |
2019
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Conference: | Seminar in Physics Department, North Dakota State University, Fargo, ND (USA), |
Document Type: |
Talk (non-conference) |
Research Program: |
Functional Macromolecules and Complexes |
Publikationsportal JuSER |
Microgels are solvent-containing, cross-linked polymer networks of colloidal size that can reversibly swell or deswell in response to external stimuli. Ionic microgels, in particular, are highly sensitive to changes in environmental conditions such as temperature, solvent quality, polymer cross-linking, suspension ionic strength and particle concentration, which allows for controlling their size and effective interaction. In this work, we theoretically study the effects of concentration-dependent deswelling of weakly-crosslinked ionic microgels on dynamic and structural suspension properties [1]. We use and compare two different theoretical approaches to calculate the equilibrium microgel size, namely the Denton-Tang method based on Poisson-Boltzmann cell model [2], and a multiparticle-based thermodynamic perturbation method [3]. In combination with an effective interaction potential for spherical ionic microgels [4], we compute static pair correlation functions and structure factors. These are used as input in our calculations of dynamic suspension properties including the hydrodynamic function, collective diffusion coefficient, and low- and high-frequency viscosities. As a consequence of the concentration-dependent deswelling, we show how the collective diffusion is enhanced while the viscosity is lowered in suspensions of ionic microgels.References[1] M. Brito, A. R. Denton and G. Nägele, to be submitted.[2] A. R. Denton and Qiyun Tang, J. Chem. Phys. 145, 164901 (2016).[3] T. J. Weyer and A. R. Denton, Soft Matter 14, 4530 (2018).[4] A. R. Denton, Phys. Rev. E 67, 011804 (2003). |