Premium
Stabilization of Liquid Foams through the Synergistic Action of Particles and an Immiscible Liquid
Author(s) -
Zhang Yi,
Wu Jie,
Wang Hongzhi,
Meredith J. Carson,
Behrens Sven H.
Publication year - 2014
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201405816
Subject(s) - capillary action , bubble , particle (ecology) , coalescence (physics) , coating , chemical engineering , materials science , suspension (topology) , colloidal particle , colloid , liquid paraffin , composite material , mechanics , oceanography , physics , mathematics , homotopy , astrobiology , pure mathematics , engineering , geology
Liquid foams are familiar from beer, frothed milk, or bubble baths; foams in general also play important roles in oil recovery, lightweight packaging, and insulation. Here a new class of foams is reported, obtained by frothing a suspension of colloidal particles in the presence of a small amount of an immiscible secondary liquid. A unique aspect of these foams, termed capillary foams, is the particle‐mediated spreading of the minority liquid around the gas bubbles. The resulting mixed particle/liquid coating can stabilize bubbles against coalescence even when the particles alone cannot. The coated bubbles are further immobilized by entrapment in a network of excess particles connected by bridges of the minority liquid. Capillary foams were prepared with a diverse set of particle/liquid combinations to demonstrate the generality of the phenomenon. The observed foam stability correlates with the particle affinity for the liquid interface formed by spreading the minority liquid at the bubble surface.