Article

Linear Viscoelastic Properties of Suspensions of Rigid Hairy Particles in a Polymeric Matrix

Authors:
• National University of La Plata, CONICET, Argentina
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Abstract

The aim of this work is to use a recently developed statistical model of dispersions with non-hydrodynamic interactions (Dagréou et al., 2002) to describe the linear viscoelastic properties of suspensions of rigid hairy particles in a polymeric matrix. We first present numerical simulations of our model applied to this system; we demonstrate that taking physical interactions into account allows one to predict the complex relaxation behaviour of filled polymers. We then compare the statistical model to experimental results on suspensions of grafted silica particles in a polystyrene matrix and show that they are in reasonable agreement up to volume fractions close to percolation. L'objectif de ce travail est d'utiliser un modèle statistique (Dagréou et al., 2002) pour décrire les propriétés viscoélastiques linéaires de polymères chargés. Nous présentons d'abord des simulations numériques du modèle appliqué à ce système; nous montrons que la prise en compte des interactions non hydrodynamiques permet de prévoir un comportement complexe en élasticité. Nous comparons ensuite le modèle avec des résultats expérimentaux obtenus pour des suspensions de particules de silice greffée dans une matrice de polystyrène; il existe un assez bon accord entre théorie et expérience, jusqu'à des fractions volumiques proches de la percolation.

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