Synthesis of Shape-Controllable Anisotropic Microparticles and "Walnut-like" Microparticles via Emulsion Interfacial Polymerization

Anisotropic Microparticles with a Controllable Structure via Soap-Free Seeded Emulsion Polymerization

Anisotropic particles have a wide range of applications in materials science such as emulsion stabilization, oil-water separation, and catalysis due to their asymmetric structure and properties. Nevertheless, designing and synthesizing large quantities of anisotropic particles with controlled morphologies continue to present considerable challenges. In this study, we successfully synthesized anisotropic microspheres using a soap-free seed emulsion polymerization method. This approach combines the benefits of seed emulsion polymerization with emulsion interfacial polymerization. By varying the concentrations of dissolved polymeric monomers, 3-methacryloyloxypropyltrimethoxysilane (MPS), and the initiator of potassium persulfate (KPS), different shapes of bowl, cap, and three-sided concave particles were obtained in surfactant-free aqueous solutions, simplifying the post-treatment process. The cap particles are Janus particles with good emulsion stability to toluene/water emulsions over 30 days. The catalytic degradation of 4-nitrophenol (4-NP) was investigated after loading silver nanoparticles on the surface of the particles by in situ deposition. The anisotropic particles obtained in this work have potential applications in emulsion stabilization and catalysis.

Synthetic Strategies for Polymer Particles with Surface Concavities

Over the past decade or so, there has been increasing interest in the synthesis of polymer particles with surface concavities, which mainly include golf ball-like, dimpled and surface-wrinkled polymer particles. Such syntheses generally can be classified into direct polymerization and post-treatment on preformed polymer particles. This review aims to provide an overview of the synthetic strategies of such particles. Some selected examples are given to present the formation mechanisms of the surface concavities. The applications and future development of these concave polymer particles are also briefly discussed. This article is protected by copyright. All rights reserved.