| Autor: |
Moussa AS; Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich , 8093 Zurich, Switzerland., Lattuada M, Conchúir BÓ, Zaccone A, Morbidelli M, Soos M |
| Jazyk: |
angličtina |
| Zdroj: |
Langmuir : the ACS journal of surfaces and colloids [Langmuir] 2013 Nov 26; Vol. 29 (47), pp. 14386-95. Date of Electronic Publication: 2013 Nov 15. |
| DOI: |
10.1021/la403240k |
| Abstrakt: |
Interactions between colloidal particles are strongly affected by the particle surface chemistry and composition of the liquid phase. Further complexity is introduced when particles are exposed to shear flow, often leading to broad variation of the final properties of formed clusters. Here we discover a new dynamical effect arising in shear-induced aggregation where repeated aggregation and breakup events cause the particle surface roughness to irreversibly increase with time, thus decreasing the bond adhesive energy and the resistance of the aggregates to breakup. This leads to a pronounced overshoot in the time evolution of the aggregate size, which can only be explained with the proposed mechanism. This is demonstrated by good agreement between time evolution of measured light-scattering data and those calculated with a population-balance model taking into account the increase in the primary particle nanoroughness caused by repeated breakup events resulting in the decrease of bond adhesive energy as a function of time. Thus, the proposed model is able to reproduce the overshoot phenomenon by taking into account the physicochemical parameters, such as pH, till now not considered in the literature. Overall, this new effect could be exploited in the future to achieve better control over the flow-induced assembly of nanoparticles. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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