Abstract
Polymeric particles are widely used owing to their tunable size and surface functionality; however, their intrinsically irregular morphology often degrades powder flowability, packing density, and compactibility, thereby limiting end-use performance. Herein, a rapid and efficient spheroidization strategy based on high- frequency electromagnetic heating (HFEH) is proposed to tailor the morphology of polymeric powders, with powder coatings employed as a model system. The sphericity of particles increased monotonically with heating temperature and residence time. Representative polymeric powders, including polyphenylene sulfide (PPS), polyamide (PA), and a hybrid powder coating, were transformed from irregular particles (sphericity = 0.65–0.69) to near-spherical ones (sphericity = 0.95–0.97), while their thermal and chemical characteristics were largely preserved. The resulting spherical powders exhibited a reduced specific surface area (1.51 to 1.43 m2/g), smaller pore size (3.9 to 3.5 nm), markedly improved flowability (angle of repose decreased by ∼3◦), and enhanced deposition efficiency (+2 to +7%). Correspondingly, coatings prepared from spherical powders showed smoother surfaces (Ra: 0.186 to 0.129 µm), lower waviness, denser microstructures (particle occupancy: 51.64 to 55.78%), and significantly improved corrosion resistance (Rpore increased by ∼103). These results demonstrate that HFEH-based spheroidization is an effective and versatile approach for optimizing the performance of polymeric powders and their derived coatings.