Fluctuation suppression in microgels by polymer electrolytes

Pasini, S.; Maccarrone, S.; Székely, N. K.; Stingaciu, L. R.; Gelissen, A. P. H.; Richtering, W.; Monkenbusch, M.; Holderer, O.

doi:10.1063/4.0000014

DOE OSTI · 1815889

Fluctuation suppression in microgels by polymer electrolytes

Pasini, S.·Maccarrone, S.·Székely, N. K.·Stingaciu, L. R.·Gelissen, A. P. H.·Richtering, W.·Monkenbusch, M.·Holderer, O.

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Abstract

Structural details of thermoresponsive, cationically poly(N-iso-propylacrylamide-co-methacrylamido propyl trimethyl ammonium chloride) microgels and the influence of the anionic electrolyte polystyrene sulfonate (PSS) on the internal structure and dynamics of the cationic microgels have been studied with a combination of small angle neutron scattering (SANS) and neutron spin echo (NSE) spectroscopy. While SANS can yield information on the overall size of the particles and on the typical correlation length inside the particles, studying the segmental polymer dynamics with NSE gives access to more internal details, which only appear due to their effect on the polymer motion. The segmental dynamics of the microgels studied in this paper is to a large extent suppressed by the PSS additive. Possible scenarios of the influence of the polyanions on the microgel structure and dynamics are discussed.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS Microgels Neutron scattering Neutron spin-echo Polymer electrolyte Spallation neutron source Spin-echo spectroscopy

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Pasini, S., Maccarrone, S., Székely, N. K., Stingaciu, L. R., Gelissen, A. P. H., Richtering, W., Monkenbusch, M., Holderer, O.. 2020-06-15. Fluctuation suppression in microgels by polymer electrolytes. https://doi.org/10.1063/4.0000014

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