A Microfluidic Approach to Synthesize Monodisperse Poly (2-Hydroxyethyl Methacrylate) Based Spherical Microgels via Water in Water Emulsion Technique

Abstract

Monodisperse spherical microdroplets of poly(2-hydroxyethyl methacrylate) (p-HEMA) were prepared by in situ UV photopolymerization process via water-in-water emulsion technique in a 3-dimentional flow-focusing microfluidic device. Due to very low interfacial tension of dispersed and continuous phases and hence their high miscibility, the microdroplets formation was assisted via a mechanical forcing with a Piezoelectric buzzer. The effects of forcing frequency and flow rate ratio on microgels size and their monodispersity were monitored by an optical microscope. The p-HEMA based microgels were characterized by FT-IR to follow the extent of photopolymerization process. The results showed that the solvent- and surfactant-free p-HEMA based monodisperse spherical microgels in the range of 19–112 µm with variation of less than 10% could be successfully synthesized at the forcing frequency of 2–40 Hz. The developed rapid microfluidic approach for synthesis of p-HEMA based spherical microgels can be used as a versatile and highly biocompatible route in green chemistry.

Keywords:

• Flow-focusing
• microfluidic
• p-HEMA
• spherical microgels
• w/w emulsion

Notes

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