Properties and Potential Applications of Liquid Marbles

Prasad Bhosale, Center for Energy Systems Research, Tennessee Technological University, Cookeville, TN 38505 and Mahesh V. Panchagnula, Dept of Mechanical Engineering, Tennessee Technological University, Cookeville, TN 38505.

Liquid marble is a term used to describe a small volume of liquid (attoliter to microliter) that is encapsulated in a hydrophobic powder. Hydrophobic powder on liquid-vapor interface facilitates controlled manipulation of this minute quantity of liquids even on hydrophilic surfaces. These marbles can potentially be applied to droplet-based microfluidic systems where drops are used as reaction chambers. We present novel properties of liquid marbles and corresponding implications towards commercial microfluidic transport applications.

Glycerin/water based liquid marbles formed using polytetrafluroethylene (PTFE) and treated fumed silica powders show excellent thermal robustness on hot surfaces (50-150 0C). This thermal robustness of liquid marbles can allow reactions at high temperature. We will present behavior of liquid marbles on hot surfaces with other novel properties like their transparency. Surface treated nanoparticulate fumed silica powders form transparent liquid marbles which allow for optical interrogation for concentration, crystal growth etc. We will also present drying of liquid marbles as potential way to controllably assemble meso/micro spheres of polymers and other solids.