%0 Journal Article
%A Kerscher, Michael
%A Lipfert, Frederik
%A Frielinghaus, Henrich
%T Exploring Hidden Local Ordering in Microemulsions with a Weak Directive Second Order Parameter
%J Chemistry Africa
%V 3
%@ 2522-5766
%C Cham
%I Springer International Publishing
%M FZJ-2020-01375
%P 703-709
%D 2020
%X So far, the near-surface ordering of microemulsions was focused on lamellar ordering while the bulk microemulsion was bicontinuous. In a series of different non-ionic surfactants the near-surface ordering of microemulsions at a hydrophilic silicon surface was studied using grazing incidence small angle neutron scattering. For the surfactant C8E3, most likely a gyroid structure was found at the solid–liquid interface, while the more efficient surfactants find lamellar ordering up to lamellar capillary condensation. The ranges for near-surface ordering are deeper than the bulk correlation lengths. These findings point towards theories that use directional order parameters that would lead to deeper near-surface ordering than simple theories with a single scalar order parameter would predict. Rheology experiments display high viscosities at very low shear rates and, therefore, support the existence of a directional order parameter.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000705288300017
%R 10.1007/s42250-020-00126-7
%U https://juser.fz-juelich.de/record/874327