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Gel and glass transition in fragile colloidal clays

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 نشر من قبل Roberta Angelini
 تاريخ النشر 2019
  مجال البحث فيزياء
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Dynamic Light Scattering (DLS) measurements were performed on colloidal suspensions of Laponitetextsuperscript{textregistered} at different concentrations in the range $C_text{w}= (1.5{div}3.0)$%. The slowing down of the dynamics induced by aging was monitored by following the temporal evolution of autocorrelation functions at different concentrations towards the gel and glass transition. Exploiting analogies with supercooled liquids approaching their glass transitions, an Angell plot for the structural relaxation times was drawn. Finally, the fragility of Laponitetextsuperscript{textregistered} suspensions at different concentrations, in different solvents, at two salt concentrations and with the addition of a polymer was reported and discussed.



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