Effects of Switching Dynamics on Solvent Recovery Efficiency from Shrinking Polymer Microdroplets

Latex particles are widely applied in inkjet printing, painting, coating, lubrication and many other areas. The current process for latex production relies on emulsion formation and separation, requiring the use of organic solvents that are flammable and volatile with negative environmental impact. In their seminal work, Jessop et al reported switchable solvents that can be hydrophilic after protonization by CO2 or other acidic stimuli (such as glycolic or formic acids), and become hydrophobic when the stimuli are removed [1]. Those solvents can be used to dissolve polymer in absence of the stimuli, forming emulsion droplets containing polymer in water. In presence of the stimuli, the solvents are converted to soluble salts that leave the droplets, leading to break up of the emulsion [1]. As such, switchable solvents provide a green and sustainable approach for latex nanoparticle synthesis in an aqueous environment [2,3]. A representative switchable solvent is N,N-Dicyclohexylmethylamine (Figure 1) with CO2 as a popular trigger.
Despite of significance for a broad range of technological applications, it remains challenging to recover switchable solvent from microdroplets containing latex nanoparticles for reuse.

Faculty Supervisor:

Xuehua Zhang

Student:

Partner:

BC Research Inc.

Discipline:

Engineering

Sector:

Clean Technology; Sustainability & the Environment; Nanotechnology

University:

University of Alberta

Program: