Domain and rim growth kinetics in stratifying foam films

ORAL

Abstract

Foam films are freely standing thin liquid films that typically consist of two surfactant-laden surfaces that are \textasciitilde 5 nm -- 10 micron apart. Sandwiched between these interfacial layers is a fluid that drains primarily under the influence of viscous and interfacial forces, including disjoining pressure. Interestingly, a layered ordering of micelles inside the foam films (thickness \textless 100 nm) leads to a stepwise thinning phenomena called stratification, which results in a thickness-dependent variation in reflected light intensity, visualized as progressively darker shades of gray. Thinner, darker domains spontaneously grow within foam films. During the initial expansion, a rim forms near the contact line between the growing thinner domain and the surrounding region, which influences the dynamics of domain growth as well as stratification Using newly developed interferometry digitial imaging optical microscopy (IDIOM) technique, we capture the rim evolution dynamics. Finally, we also develop a theoretical model to describe both rim evolution and domain growth dynamics.

Authors

  • Yiran Zhang

    Univ of Illinois - Chicago, Chemical Engineering, University of Illinois at Chicago, University of Illinois at Chicago

  • Subinuer Yilixiati

    Univ of Illinois - Chicago, Chemical Engineering, University of Illinois at Chicago, University of Illinois at Chicago

  • Vivek Sharma

    Univ of Illinois - Chicago, Chemical Engineering, University of Illinois at Chicago, University of Illinois at Chicago