Colloidal Dispersion Stability: Kinetic Modeling of Agglomeration and Aggregation

Autor: Paulo A. Netz, Luana Almeida Fiel, Guilherme K. Gonzatti, Adriana Raffin Pohlmann
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: Journal of the Brazilian Chemical Society v.26 n.2 2015
Journal of the Brazilian Chemical Society
Sociedade Brasileira de Química (SBQ)
instacron:SBQ
Journal of the Brazilian Chemical Society, Volume: 26, Issue: 2, Pages: 373-380, Published: FEB 2015
Popis: In this work we present a simple model for the kinetics of agglomeration and aggregation of colloidal particles. We consider that particles agglomerate rapidly and endothermically forming oligomers. These oligomers can, in turn, aggregate irreversibly, in a process that leads to the destabilization of the colloidal system. As these two processes have very different relative energy activations, they occur in different time-scales: the first step is faster and reaches a state of quasi‑equilibrium. Because of this, the enthalpy change during the agglomeration can be experimentally determined through the variable temperature multiple light scattering (VTMLS) method. Interestingly, this value is related to the relative kinetic stability of the system and can be used to evaluate the stability of new colloidal compositions. Our results are in qualitative agreement with experimental data of low concentration colloidal dispersions consisted of polymer particles and/or surfactant-coated particles.
Databáze: OpenAIRE