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We present a study of water adsorption behavior in confined media by using on the one hand a nonlocal density functional theory (NLDFT) coupled with the statistical associative fluid theory for potential of variable range (SAFT-VR) equation of state and, on the other hand, grand canonical Monte Carlo (GCMC) molecular simulations. The present work is a second step in an ongoing NLDFT/SAFT-VR coupling. The first step has focused on the monomer contribution and especially on the way to extend the dispersive terms of the monomer contribution of SAFT-VR in the NLDFT formalism. In the present work, the theory has been extended by introducing the associating contribution due to hydrogen bonding and is applied to water, which is modeled as one sphere with four identical associating sites placed in a tetrahedral geometry with the same interaction parameters for both theory and simulations. NLDFT/SAFT-VR and GCMC results for density distributions of water in graphitic slit-like micropores and mesopores are shown to be in good agreement. Moreover, the capillary condensation and evaporation were investigated with the theoretical model in micro- and mesopores and also in the case of activated surfaces.

Abstract. We present a new approach to describe the rheological properties of dispersions with non-hydrodynamic interactions (steric, electrostatic and Van der Waals interactions) in the linear viscoelastic domain. Our model is based on the calculation of additional stresses resulting from interaction potentials between spheres and Brownian motion. We start from the statistical mechanical approaches which have been developed by Batchelor and Green and later Lionberger and Russel, to model the viscoelastic properties of emulsions and suspensions. We have extended their calculations to the more general case of viscoelastic deformable inclusions in a viscoelastic matrix. Our contribution lies in the computation of the hydrodynamic functions involved in the term describing interaction stresses. This computation is based on Palierne's results on the deformation field around a viscoelastic inclusion embedded in a viscoelastic matrix. We have also rewritten the conservation equation in the case of interest, over the whole frequency domain. We finally express the complex shear modulus of the dispersion as the sum of two terms : Palierne's complex shear modulus gives the purely hydrodynamic contribution; the interaction contribution depends on both the hydrodynamic properties and the interaction potential.