Continuous fabrication of core-shell aerogel microparticles using microfluidic flows

Nicholas Teo; Chenxi Jin; Akshata Kulkarni; Sadhan C Jana

doi:10.1016/j.jcis.2019.11.053

Continuous fabrication of core-shell aerogel microparticles using microfluidic flows

J Colloid Interface Sci. 2020 Mar 1:561:772-781. doi: 10.1016/j.jcis.2019.11.053. Epub 2019 Nov 15.

Authors

Nicholas Teo¹, Chenxi Jin¹, Akshata Kulkarni¹, Sadhan C Jana²

Affiliations

¹ Department of Polymer Engineering, The University of Akron, 250 South Forge Street, Akron, OH 44325-0301, United States.
² Department of Polymer Engineering, The University of Akron, 250 South Forge Street, Akron, OH 44325-0301, United States. Electronic address: janas@uakron.edu.

PMID: 31761464
DOI: 10.1016/j.jcis.2019.11.053

Abstract

This work focuses on fabrication of core-shell polyimide aerogel microparticles with and without a surfactant via oil-in-oil-in-oil (O/O/O) emulsion system aided by a simple microfluidic device. A double emulsion is formed through sequential, step-wise emulsification of co-flowing core and shell organic liquid streams in a simple microfluidic setup. The polyimide sol, introduced as the shell liquid, undergoes accelerated polymerization in a heated silicone oil bath to yield a porous polyimide shell around silicone oil core that eliminates the possibility of droplet coalescence or rupture. The core-shell gel microparticles are then isolated and supercritically dried to obtain core-shell aerogel microparticles. The diameter and shell thickness of hollow microparticles are studied as function of liquid flowrates in the microfluidic device and the viscosity of the shell liquid.

Keywords: Aerogels; Core-shell; Double emulsion; Microfluidics; Polyimide.