Competitive Adsorption between a Polymer and Solvents onto Silica.

In polymer nanocomposites, particle-polymer interactions play a key role both in the processing and in the final properties of the obtained materials. Specifically, for silica, because of the surface polarity, surface modification is commonly used to improve the compatibility with apolar polymer matrices in order to prevent agglomeration. In this work, a new way to investigate the polymer-silica affinity and determine dispersibility parameters (HDP) of silica particles in the 3D Hansen space using a solvent approach is proposed.

Aortic atherosclerosis is a key modulator of the prognostic value of postural blood pressure changes.

Background And Aims: Orthostatic blood pressure decrease or increase has been related to cardiovascular events in hypertensive patients. Large blood pressure changes after orthostatic stress are associated with autonomic and neurohormonal abnormalities; aortic atherosclerosis (ATS) may also play a role.

Methods: We investigated the interaction of ATS on the prognostic value of postural blood pressure changes.

Polymorphism of natural fatty acid liquid crystalline phases.

We study the phase behavior in water of a mixture of natural long chain fatty acids (FAM) in association with ethylenediamine (EDA) and report a rich polymorphism depending on the composition. At a fixed EDA/FAM molar ratio, we observe upon dilution a succession of organized phases going from a lamellar phase to a hexagonal phase and, finally, to cylindrical micelles. The phase structure is established using polarizing microscopy, SAXS, and SANS.