The life of a bicontinuous Pickering emulsion: structure, dynamics and the role of particle size
Bicontinuous particle-stabilized emulsions (christened bijels) form a versatile class of soft materials with a host of potential technological applications, e.g. tissue engineering, catalysis and energy applications. They are also an immensely interesting form of non-equilibrium arrested system, with open questions about their long-term stability and the effect of processing parameters (quench rate, particle size) on their structure and dynamics. Recently, we have adapted a system of water/lutidine (an oil) to prepare bijels using silica nanoparticles as opposed to microparticles, with intriguing differences being observed. By performing a topological analysis on the macroscopic bijel structure, along with diffusing-wave spectroscopy which can probe movement on the particle scale, we have explored how the aforementioned processing parameters influence the bijel structure and dynamics. In so doing, we have quantitatively described how to optimize the bijel structure, as well as suggesting that the bijel may not be completely arrested over long timescales.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..