Title of article :
Shake-gels: shear-induced gelation of laponite–PEO mixtures
Author/Authors :
Zebrowski، نويسنده , , J and Prasad، نويسنده , , V and Zhang، نويسنده , , W and Walker، نويسنده , , L.M and Weitz، نويسنده , , D.A، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2003
Pages :
9
From page :
189
To page :
197
Abstract :
Suspensions of clay particles (laponite), mixed with poly(ethylene oxide) (PEO) undergo a dramatic shear thickening when subjected to vigorous shaking, which transforms them from a low viscosity fluid into a ‘shake-gel’, a solid with elasticity sufficient enough to support its own weight. The shake-gel is reversible, relaxing back to a fluid with a relaxation time that is strongly dependent on PEO concentration. Shake-gels are observed for PEO concentrations slightly below the threshold for complete saturation of the laponite particles by the polymer. Light scattering measurements confirm that the PEO is adsorbed on the surface of the laponite particles, and suggests that shear induces a bridging between the colloidal particles, resulting in a gel network which spans the system. Desorption of the polymer reduces the bridging and thus relaxes the network.
Keywords :
Laponite , Poly(ethylene oxide) , Adsorption , Relaxation , gelation
Journal title :
Colloids and Surfaces A Physicochemical and Engineering Aspects
Serial Year :
2003
Journal title :
Colloids and Surfaces A Physicochemical and Engineering Aspects
Record number :
1785589
Link To Document :
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