Scalable Synthesis of Janus Particles with High Naturality

Because of the increasing concerns about the ecological damage and negative health effects that may be caused by petrochemical-based microbeads, many countries are banning their use in a wide range of consumer products. One particular class of particles that may never reach their full potential because of such a ban is Janus particles, which are particles with two opposite properties. Despite significant progress in the scalable synthesis of Janus particles, most studies rely on petrochemical-based materials and solvents to enable their synthesis. In this report, we present a single-emulsion polymerization method for scalable synthesis of amphiphilic Janus particles with materials derived from plants. Soybean oil-epoxidized acrylate (SBOEA) monomers are polymerized in single-emulsion droplets of SBOEA, ethyl cellulose (EC), butyl acetate, and initiators that can be generated by either bulk or microfluidic emulsification, leading to the formation of amphiphilic soybean oil polymer/EC (SBOP/EC) Janus particles. Interfacial anchoring of the in situ-formed SBOP particles at the interface of the emulsion droplet plays a key role in the formation of the SBOP/EC Janus particles. Large-scale preparation of uniform SBOP/EC Janus particles is also demonstrated using a glass-silicon microfluidic device. Finally, the SBOP/EC Janus particles show potential to stabilize oil-in-water emulsions that can stay stable under flowing conditions.