Electrochemically Initiated Synthesis of Polyacrylamide\nMicrogels and Core-shell Particles

Abstract

Herein, we developed\na simple procedure for synthesizing micrometer-sized\nmicrogel particles as a suspension in an aqueous solution and thin\nfilms deposited as shells on different inorganic cores. A sufficiently\nhigh constant potential was applied to the working electrode to commence\nthe initiator decomposition that resulted in gelation. Under hydrodynamic\nconditions, this initiation allowed preparing different morphology\nmicrogels at room temperature. Importantly, neither heating nor UV-light\nillumination was needed to initiate the polymerization. Moreover,\nthin films of the cross-linked gel were anchored on different core\nsubstrates, including silica and magnetic nanoparticles. Scanning\nelectron microscopy and transmission electron microscopy imaging confirmed\nthe microgel particles’ and films’ irregular shape and\nporous structure. Energy-dispersive X-ray spectroscopy indicated that\nthe core coating with the microgel film was successful. Dynamic light\nscattering measured the micrometer size of gel particles with different\ncombinations of acrylic monomers. Thermogravimetric analysis and the\nfirst-derivative thermogravimetric analysis revealed that the microgels’\nthermal stability of different compositions was different. Fourier-transform\ninfrared and ¹³C NMR spectroscopy showed successful copolymerization\nof the main, functional, and cross-linking monomers.