Time-dependent strength of colloidal gels.

نویسندگان

S Manley

Benny Davidovitch

Neil R Davies

L Cipelletti

A E Bailey

R J Christianson

U Gasser

V Prasad

P N Segre

M P Doherty

S Sankaran

A L Jankovsky

B Shiley

J Bowen

J Eggers

C Kurta

T Lorik

D A Weitz

چکیده

Colloidal silica gels are shown to stiffen with time, as demonstrated by both dynamic light scattering and bulk rheological measurements. Their elastic moduli increase as a power law with time, independent of particle volume fraction; however, static light scattering indicates that there are no large-scale structural changes. We propose that increases in local elasticity arising from bonding between neighboring colloidal particles can account for the strengthening of the network, while preserving network structure.

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