Experimental studies on the rheology of hard-sphere suspensions near the glass transition

Journal Article · Thu Feb 08 04:00:00 EST 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100366a030· OSTI ID:7201766

Marshall, L; Zukoski, IV, C F ^[1]

---

1. Univ. of Illinois, Urbana (USA)

We have investigated the rheological behavior of sterically stabilized colloidal silica particles of three different sizes at volume fractions above 0.5. Despite a small surface charge, which elevated the intrinsic viscosity from the Einstein value of 2.5, the particles were found to behave essentially as hard spheres in the concentrated suspensions and to have properties highly reminiscent of molecular glasses. The zero shear rate viscosity, characteristic of disordered suspensions and present at all volume fractions, diverges as {phi} {yields} 0.6 and is well-described by the Doolittle equation for glassy flow. For suspensions with a relative zero shear rate viscosity greater than 5 {times} 10{sub 2}, shear thickening was observed. Characteristic time scales for particle rearrangement determined from critical shear rates for shear thinning and shear thickening were found to follow trends predicted for molecular glasses. A transition from a liquid like linear relaxation response to glassy stretched exponential behavior was observed as volume fraction was increased. The onset of the glassy relaxation response, indicative of nondecaying correlations, occurred near a volume fraction of 0.52.

• DOE Contract Number: AC02-76ER01198
• OSTI ID: 7201766
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:3; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603 -- Materials-- Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400200* -- Inorganic
Organic
& Physical Chemistry
CALCULATION METHODS
CHALCOGENIDES
COLLOIDS
DATA ANALYSIS
DISPERSIONS
GLASS
HARD-SPHERE MODEL
MEASURING INSTRUMENTS
MEASURING METHODS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PARTICLES
RHEOLOGY
SILICA
SILICON COMPOUNDS
SILICON OXIDES
VISCOSITY