%0 Journal Article
%A Holmqvist, P.
%A Mohanty, P.S.
%A Nägele, G.
%A Schurtenberger, P.
%A Heinen, M.
%T Structure and Dynamics of Loosely Cross-Linked Ionic Microgel Dispersions in the Fluid Regime
%J Physical review letters
%V 109
%@ 0031-9007
%C College Park, Md.
%I APS
%M PreJuSER-111854
%P 048302
%D 2012
%Z We thank Simon Rogers (Research Centre Julich) for carefully proofreading the letter. P. S. M. and P. S. acknowledge financial support from the Swiss National Science Foundation. G. N. and M. H. acknowledge support from the Deutsche Forschungsgemeinschaft (project B2 in SFB-TR6).
%X We report a comprehensive experimental-theoretical study of the temperature-and concentration-dependent swelling behavior of weakly cross-linked PNiPAm ionic microgel particles in the deionized fluid phase. The particles swell reversibly when the dispersion is cooled from the collapsed state to lower temperatures. While the collapsed state shows no dependence on the microgel number density, the swelling at lower T is more pronounced at lower concentrations. The static pair correlations and short-time diffusion functions, and the concentration and temperature dependence of the microgel radius and effective charge, are studied using static and dynamic light scattering in combination with state-of-the-art analytical theoretical schemes based on a Yukawa-type effective pair potential and a core-shell model. We show that only such a combined, simultaneous fit of static and dynamic scattering functions allows for an unambiguous determination of the microgel radius and effective charge.
%K J (WoSType)
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000306933000012
%R 10.1103/PhysRevLett.109.048302
%U https://juser.fz-juelich.de/record/111854