Rheological behaviour of polyoxometalate-doped lyotropic lamellar phases
Laboratoire de Physique des Solides-UMR 8502-Université Paris-Sud, F-91405, Orsay, France
2 Laboratoire Matière et Systèmes Complexes-10 rue Alice Domon et Lonie Duquet, 75205, Paris, France
3 SOLEIL Synchrotron-L’Orme des Merisiers Saint-Aubin, BP 48 91192, Gif-sur-Yvette, France
Accepted: 25 November 2010
Published online: 10 January 2011
We study the influence of nanoparticle doping on the lyotropic liquid crystalline phase of the industrial surfactant Brij30 ( C12E4 and water, doped with spherical polyoxometalate nanoparticles smaller than the characteristic dimensions of the host lamellar phase. We present viscometry and in situ rheology coupled with small-angle X-ray scattering data that show that, with increasing doping concentration, the nanoparticles act to decrease the shear viscosity of the lamellar phase, and that a shear-induced transition to a multilamellar vesicle “onion” phase is pushed to higher shear rates, and in some cases completely suppressed. X-ray data reveal that the nanoparticles remain encapsulated within the membranes of the vesicles, thus indicating a viable method for the fabrication of nanoparticle incorporating organic vesicles.
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2011