M. Benhamou^1,2, F. Elhajjaji¹, K. Elhasnaoui¹, and A. Derouiche¹

¹ Polymer Physics and Critical Phenomena Laboratory

Sciences Faculty Ben M'sik, P.O. Box 7955, Casablanca, Morocco

² Moulay Ismail University, Meknes, Morocco

Abstract. In this work, we consider a low-density assembly of nanoparticles that are immersed in a critical cross-linked polymer blend, made of two polymers of different chemical nature. We assume that, near the spinodal temperature at which the mixture exhibits a microphase separation, the nanoparticles preferentially adsorb one of the two polymers. The consequence is that, these nanoparticles aggregate in the non-preferred phase. The aim is an extensive study of the thermodynamical properties of the nanoparticles aggregation, under a change of a suitable parameter such as temperature. This phase transition drives the nanoparticles from a dispersed phase to a dense one. To this end, we elaborate a new field theory that allows the determination of the effective free energy of the mobile nanoparticles, as a functional of their density. From this effective free energy, we draw the phase diagram in nanoparticle volume fraction-temperature plane, and investigate all critical properties of the nanoparticles flocculation, from a static and dynamic point of view. Finally, the discussion is extended to impregnated cross-linked polymer blends in solution.

Keywords: Cross-linked polymer blends – Nanoparticles – Aggregation – Phase diagram.