Strain Hardening of Fractal Colloidal Gels
نویسندگان
چکیده
We report on experiments on the rheology of gels formed by diffusion-limited aggregation of neutrally buoyant colloidal particles. These gels form very weak solids, with the elastic modulus, G0svd, larger than the loss modulus, G00svd, and with both G0svd and G00svd exhibiting only a very weak frequency dependence. Upon small but finite strains g , 0.45 the elastic modulus increases roughly exponentially with g2. We explain the observed strain hardening with the highly nonlinear elastic response of the rigid backbone of the gel to elongational deformation. [S0031-9007(98)08309-4]
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