Architecture and Performance of Raspberry-like Colloidal Particle Clusters via Self-Assembly of in Situ Generated Janus Particles

Uniform raspberry-like poly(vinylidene fluoride)/polystyrene (PVDF/PS) complex colloidal particle clusters (CCPCs) with PVDF seed particles protruding outward are fabricated by a novel and one-step approach: soap-free seeded emulsion polymerization following single-electron transfer radical polymerization (SET-RP) mechanism. The driving force from different hydrophobicity values between PVDF and PS induces the self-assembly of the first formed Janus particles, which can be caught because of the relatively low rate of SET-RP, and then Pickering emulsion polymerization performs continuously because of the presence of the unreacted St monomers to form the CCPCs. In contrast, the raspberry-like CCPCs cannot be achieved via a relatively high rate of conventional radical polymerization. In addition, the static water contact angle of the latex nanocoating prepared with the obtained raspberry-like CCPCs is 169.6° and remains at 155° after ultraviolet (UV) irradiation for 6 h. Therefore, it is expected to lead to superhydrophobic and anti-UV functional coatings.