Interfacial characteristics and the stability mechanism of a dispersed particle gel (DPG) three-phase foam

Abstract

Dispersed particle gel (DPG) was added to foams to obtain a more stable foam system: the DPG three-phase foam. Film drainage, interfacial rheology, and stability mechanism of the DPG three-phase foam were studied. The foam volume of the DPG three-phase foam was slightly higher than that of the traditional foam, and the half-decay time was five times that of the traditional foam. The results of film drainage show that DPG particles mainly improve the stability of thin films, i.e., the ability to bond with and capture water. Interfacial characteristics were investigated by the interfacial tension relaxation method. DPG particles slowed down the overall molecular relaxation process of the foam system, which enhanced the viscoelasticity and the mechanical strength of the interface. The stability mechanism can be explained as follows. The adsorption between DPG particles and Tetradecyl hydroxyl sulfobetaine (THSB) occurs owing to the hydrophobic attractive interaction. Therefore, DPG particles aggregate at the interface to form a shell structure, which increases the mechanical strength of the thin film by its low relaxation process; thus, a stable interface is formed, and the stability of the foam is enhanced.