Synthesis of V-notched half-open polymer microspheres via facile solvent-tuned self-assembly

Asymmetric structures have attracted much attention owing to their potential application in drug delivery, optoelectronics and catalysis. However, current reported works for the preparation of asymmetric particles rely mainly on emulsion, seeding, hydrothermal and templating approaches, but facile strategies are seldom developed. Herein, we first utilize low-cost monomers of thiourea and formaldehyde to fabricate a peculiar V-notched half-open polymer architecture via a facile precipitation polymerization method in a mixed solvent of water/ethanol (1 : 1 v/v) at room temperature, where the volume ratio between water and ethanol can adjust the open angle of the microspheres. Impressively, this method is readily carried out, and no templates, surfactants, hydrothermal devices, complex procedures or toxic solvents are utilized. This synthetic strategy provides a facile approach to prepare V-notched half-open polymer microspheres with potential for materials engineering.