Aqueous particle stabilized foams can be found in many technical applications and food products. In these systems the particles adsorb at the air-liquid interfaces of the foam and stabilize them. When altering the properties of the particles like their hydrophobicity, the properties of the produced foams can be changed. Typical particles are modified silica nanospheres, but also soft colloidal particles like proteins, especially in food-related systems. Another class of soft colloidal particles are cross-linked, short-chained poly-N-isopropylacrylamide (NIPAM) polymers, which have attracted much attention during the last years and were studied with various techniques and in the context of multiple possible applications. Since these microgels are responsive to external stimuli like temperature, materials made from them can be considered “smart” materials. A prominent example are thermo-responsive emulsions stabilized by microgel particles adsorbed at the water-oil interface. In these systems the emulsion stability can be controlled by changing the temperature. In this contribution we report on our experiments with aqueous foams, which are stabilized by PNIPAM microgel particles. We present how microgel properties like size, cross-linking density and particle concentration can influence the properties of macroscopic foams prepared with them. In addition we try to shine light on the interactions in microgel-loaded thin liquid films by analyzing disjoining pressure isotherms recorded with a Thin Film Pressure Balance (TFPB).

Macroscopic aqueous foams stabilized by PNIPAM microgels

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.