Polymer Microparticles with Controllable Surface Textures Generated through Interfacial Instabilities of Emulsion Droplets

Abstract

A general and versatile route to prepare hierarchical polymer microparticles via interfacial instabilities of emulsion droplets is demonstrated. Uniform emulsion droplets containing hydrophobic polymers and n‐hexadecanol (HD) are generated through microfluidic devices. When organic solvent diffuses through the aqueous phase and evaporates, shrinking emulsion droplets containing HD and polystyrene (PS) will trigger interfacial instabilities to form microparticles with wrinkled surfaces. Interestingly, surface‐textures of the particles can be accurately tailored from smooth to high textures by varying the HD concentration and/or the rate of solvent evaporation. Moreover, composite particles can be generated by suspending different hydrophobic species to the initial polymer solutions. This versatile approach for preparing particles with highly textured surfaces can be extended to other type of hydrophobic polymers which will find potential applications in the fields of drug delivery, tissue engineering, catalysis, coating, and device fabrication.

Fabrication of porous polymer microspheres by tuning amphiphilicity of the polymer and emulsion–solvent evaporation processing

“…Upon irradiation by a linearly polarized light, the aggregates could be elongated [39,40]. However, most of these previous studies were conducted with simple and relatively small aggregates, such as spheres, vesicles [41][42][43][44][45].…”

Surface Wrinkling on Polydimethylsiloxane Microspheres via Wet Surface Chemical Oxidation

“…Furthermore, the detailed information regarding the complicated surface oxidation has been revealed by in-situ optical microscope observation, which appears to be impossible to achieve in a planar system. Compared with the previous studies22232425262728303132, our system and the method developed here have the following advantages. Surface oxidation processing provides a simple, rapid, scalable, high-output method to generate the stiff oxidized shell on the microspheres and simultaneously trigger surface wrinkles on the spherical surface.…”

The design of wrinkled microcapsules for enhancement of release rate

“…In recent years, significant efforts have been devoted to buckling of planar films [4][5][6][7][8][9][10][11][12][13][14][15]. But, only few studies have been conducted on creation of wrinkled core-shell particles, which requires multiple deposition steps on a designer substrate [16][17][18][19][20]. To the best of our knowledge, synthetic procedures for preparation of consistently wrinkled microcapsules for controlled release have not been reported.…”