Pickering miniemulsion polymerization using Laponite clay as a stabilizer

Area of Science:

• Polymer Chemistry
• Materials Science
• Nanotechnology

Background:

• Pickering emulsions utilize solid particles as stabilizers.
• Miniemulsion polymerization offers control over particle size and morphology.
• Laponite clay discs present a novel stabilizer for miniemulsion systems.

Purpose of the Study:

• To investigate solid-stabilized miniemulsion polymerizations using Laponite clay discs.
• To characterize the resulting armored latex particles.
• To analyze polymerization kinetics and develop a predictive model for particle size.

Main Methods:

• Free radical polymerization of hydrophobic monomers (styrene, acrylates).
• Stabilization using Laponite clay discs in a miniemulsion system.
• Characterization via scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM).
• Kinetic studies using gravimetry.

Main Results:

• Formation of armored latex particles with surfaces covered by Laponite clay discs.
• Evidence of compartmentalization in Pickering miniemulsion polymerization compared to bulk polymerization.
• Observed retardation effects, more pronounced in smaller particles, attributed to Laponite clay.
• Development of a model predicting latex particle size based on monomer and stabilizer concentrations.

Conclusions:

• Laponite clay is an effective stabilizer for miniemulsion polymerization, yielding armored latexes.
• The study demonstrates compartmentalization and clay-induced kinetic effects.
• A predictive model highlights the linear correlation between clay disc number and latex particle surface area under specific conditions.
• The reversible adhesion of Laponite clay discs is crucial for the observed phenomena.