Shear stresses of colloidal dispersions at the glass transition in equilibrium and in flow

Abstract

We consider a model dense colloidal dispersion at the glass transition, and investigate the connection between equilibrium stress fluctuations, seen in linear shear moduli, and the shear stresses under strong flow conditions far from equilibrium, viz. flow curves for finite shear rates. To this purpose thermosensitive core-shell particles consisting of a polystyrene core and a crosslinked poly(N-isopropylacrylamide)(PNIPAM) shell were synthesized. Data over an extended range in shear rates and frequencies are compared to theoretical results from integrations through transients and mode coupling approaches. The connection between non-linear rheology and glass transition is clarified. While the theoretical models semi-quantitatively fit the data taken in fluid states and the predominant elastic response of glass, a yet unaccounted dissipative mechanism is identified in glassy states.

17 pages, 11 figures; J. Chem. Phys. in print (2008)

References in corpus (3)

• Strain-Rate Frequency Superposition (SRFS) - A rheological probe of structural relaxation in soft materials
• Three-dimensional imaging of colloidal glasses under steady shear
• Dense colloidal suspensions under time-dependent shear

Cited by in corpus (12)

• Glass Rheology: From mode-coupling theory to a dynamical yield criterion
• A mode coupling theory for Brownian particles in homogeneous steady shear flow
• Viscoelasticity and shear flow of concentrated, non-crystallizing colloidal suspensions: Comparison with Mode-Coupling Theory
• Nonlinear rheology of colloidal dispersions
• A First-Principles Constitutive Equation for Suspension Rheology
• Overshoots in stress strain curves: Colloid experiments and schematic mode coupling theory
• Start-up Shear of Concentrated Colloidal Hard Spheres: Stresses, Dynamics and Structure
• Coupling of Rotational Motion with Shape Fluctuations of Core-shell Microgels Having Tunable Softness
• Glass and Jamming Rheology in Soft Particles Made of PNIPAM and Polyacrylic Acid
• Thermoresponsive Colloidal Molecules
• Transient stress evolution in repulsion and attraction dominated glasses
• Schematic Mode Coupling Theory of Glass Rheology: Single and Double Step Strains