Interfacial dynamics and rheology of polymer-grafted nanoparticles at air-water and xylene-water interfaces

Nicolas J. Alvarez, Shelley L. Anna, Trishna Saigal, Robert D. Tilton, Lynn M. Walker

Research output: Contribution to journalArticlepeer-review

104 Scopus citations

Abstract

Particle-stabilized emulsions and foams offer a number of advantages over traditional surfactant-stabilized systems, most notably a greater stability against coalescence and coarsening. Nanoparticles are often less effective than micrometer-scale colloidal particles as stabilizers, but nanoparticles grafted with polymers can be particularly effective emulsifiers, stabilizing emulsions for long times at very low concentrations. In this work, we characterize the long-time and dynamic interfacial tension reduction by polymer-grafted nanoparticles adsorbing from suspension and the corresponding dilatational moduli for both xylene-water and air-water interfaces. The dilatational moduli at both types of interfaces are measured by a forced sinusoidal oscillation of the interface. Surface tension measurements at the air-water interface are interpreted with the aid of independent ellipsometry measurements of surface excess concentrations. The results suggest that the ability of polymer-grafted nanoparticles to produce significant surface and interfacial tension reductions and dilatational moduli at very low surface coverage is a key factor underlying their ability to stabilize Pickering emulsions at extremely low concentrations.

Original languageEnglish (US)
Pages (from-to)8052-8063
Number of pages12
JournalLangmuir
Volume28
Issue number21
DOIs
StatePublished - May 29 2012
Externally publishedYes

Fingerprint

Dive into the research topics of 'Interfacial dynamics and rheology of polymer-grafted nanoparticles at air-water and xylene-water interfaces'. Together they form a unique fingerprint.

Cite this