Choi, Ye Hun Lee, Sang Seok Lee, Dong-Myeong Jeong, Hyeon Su Kim, Shin-Hyun 2024-01-19T18:03:05Z 2024-01-19T18:03:05Z 2021-09-04 2020-03 1613-6810 https://pubs.kist.re.kr/handle/201004/118934 Microgels, microparticles made of hydrogels, show fast diffusion kinetics and high reconfigurability while maintaining the advantages of hydrogels, being useful for various applications. Here, presented is a new microfluidic strategy for producing polymer-graphene oxide (GO) composite microgels without chemical cues or a temperature swing for gelation. As a main component of microgels, polymers that are able to form hydrogen bonds, such as polyvinyl alcohol (PVA), are used. In the mixture of PVA and GO, GO is tethered by PVA through hydrogen bonding. When the mixture is rapidly concentrated in the core of double-emulsion drops by osmotic-pressure-driven water pumping, PVA-tethered GO sheets form a nematic phase with a planar alignment. In addition, the GO sheets are linked by additional hydrogen bonds, leading to a sol-gel transition. Therefore, the PVA-GO composite remains undissolved when it is directly exposed to water by oil-shell rupture. These composite microgels can be also produced using poly(ethylene oxide) or poly(acrylic acid), instead of PVA. In addition, the microgels can be functionalized by incorporating other polymers in the presence of the hydrogel-forming polymers. It is shown that the multicomponent microgels made from a mixture of polyacrylamide, PVA, and GO show an excellent adsorption capacity for impurities. English Wiley - V C H Verlag GmbbH & Co. Composite Microgels Created by Complexation between Polyvinyl Alcohol and Graphene Oxide in Compressed Double-Emulsion Drops Article 10.1002/smll.201903812 1 Small, v.16, no.9 Small 16 9 N scie scopus 000486243000001 2-s2.0-85073796074 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article MICROFLUIDIC FABRICATION POLY(VINYL ALCOHOL) HYDROGEL BEADS CARBON DOTS REMOVAL ENCAPSULATION DISPERSIONS ADSORPTION STABILITY RELEASE double-emulsion drops graphene oxide hydrogen bonds microgels nematic phase