Scalable Production of Polymer Nanocolloids with Complex Internal Structures and Amphiphilic Properties via Flash NanoPrecipitation

Polymer nanocolloids with complex internal structures, including anisotropic Janus nanocolloids and patchy particles, have generated significant interest for their potential applications in medicine and optics and for their unique self-assembly behavior. However, nanocolloids with such complex internal structures often require highly specific chemistries and multiple processing steps with long residence times, making a processing platform which can generate kilograms of such structured nanocolloids per day highly desirable. Here, we demonstrate the ability to produce these structured polymer nanocolloids using Flash NanoPrecipitation (FNP). During FNP, nanocolloids form when polymers precipitate and phase separate upon rapid mixing of a polymer blend in a good solvent with a poor solvent, and the resulting nanocolloid morphology is determined by the minimization of the surface free energy of the system. We are able to produce core-shell, spherical Janus, and snowman Janus polymer nanocolloids by tuning interactions between the polymers and the solvent environment. Additional functionality can be incorporated by adding inorganic nanoparticles and reacting hydrophilic moieties onto one half of the nanocolloid, making them amphiphilic for potential application as solid surfactants.