Tio₂‐ or tio₂/fe₃o₄‐containing PVA‐based microgels for controlled photocatalytic degradation of methyl orange

An inverse emulsion radical reaction was adopted to prepare poly(vinyl alcohol) (PVA)‐based microgels that contained titanium oxide (TiO₂) or TiO₂/Fe₃O₄, and the obtained microgels were applied to catalyze the degradation of methyl orange. First, well‐defined PVA was used to synthesize a PVA‐based macromonomer (PVAM) that contained carbon–carbon double bonds of tunable contents. Then, the composite microgels were prepared via the crosslinking reaction between PVAM and acrylic acid in the presence of TiO₂ or TiO₂/Fe₃O₄. Thermogravimetric analysis (TGA) and scanning electron microscope observation confirmed that the inorganic nanoparticles were well encapsulated within the microgels. TGA results showed that the loading efficiency of TiO₂ was able to be controlled by varying the structure of PVAM. It was found that the microgels can efficiently catalyze the degradation of methyl orange. Moreover, the composite microgels possessed controllable and returnable catalysis ability. In addition, the separation of the composite microgels from aqueous solution could be quite easily accomplished by incorporating magnetic particles. POLYM. COMPOS., 38:132–137, 2017. © 2015 Society of Plastics Engineers