Unique Oil-in-Brine Pickering Emulsion Using Responsive Antipolyelectrolyte Functionalized Latex: A Versatile...

Area of Science:

• Materials Science
• Colloid and Surface Chemistry
• Polymer Science

Background:

• Stabilizing emulsions in challenging environments like high salinity and temperature is crucial for industrial applications.
• Traditional emulsion stabilizers often fail under extreme conditions, necessitating novel approaches.
• Zwitterionic materials offer unique properties for interfacial stabilization.

Purpose of the Study:

• To develop a simple method for synthesizing zwitterion-functionalized latexes for emulsion stabilization.
• To investigate the antipolyelectrolyte behavior and stability of these latexes in high salinity and temperature.
• To demonstrate the efficacy of these functionalized latexes in creating stable oil-in-water Pickering emulsions.

Main Methods:

• Emulsifier-free emulsion copolymerization using a sulfobetaine comonomer in brine.
• Characterization of functionalized latex particles using DLS, SEM, TEM, XPS, and TGA.
• Evaluation of emulsion stability under varying salinity, temperature, and pH conditions.

Main Results:

• Well-defined zwitterion-functionalized latexes exhibiting antipolyelectrolyte behavior were synthesized.
• The latex particles demonstrated excellent long-term stability in high salinity brine and at elevated temperatures.
• Stable oil-in-water Pickering emulsions were formed with low solid content (<0.02% w/w) using 50% v/v n-decane.
• Self-assembly of latexes into spherical colloidosomes at the oil-water interface via hydrophobic interactions and irreversible adsorption.

Conclusions:

• Zwitterion-functionalized latexes are effective stabilizers for oil-in-water emulsions in complex environments.
• The saltphilic nature and antipolyelectrolyte behavior contribute to their performance in high salinity and temperature.
• These novel latexes offer a versatile alternative for emulsion stabilization in demanding industrial applications.