Adsorbents for Organic Dyes Based on PDMAEMA/POSS Hybrid Material via Thiol-Michael Addition Reaction

The organic/inorganic hybrid material of poly[2-(dimethyl amino)-ethyl methacrylate]/polyhedral oligomeric silsesquioxane (POSS–PDMAEMA) was synthesized via a thiol-Michael addition reaction. The structures of POSS–PDMAEMA and its self-assembly in aqueous solution were confirmed by 1H-NMR, TEM, DLS, UV–Vis and fluorescence spectrum. In aqueous solutions, POSS–PDMAEMA could self-assemble into micelles and its critical micelle concentration was 12.4 mg/L. POSS–PDMAEMA micelles can adsorb dyes efficiently, it could adsorb methyl red at a concentration of 10–100 mg/L and dithizone at a concentration of 20–100 mg/L, and could remove 98% methyl red and 90% dithizone within 30 s. Due to the good temperature and pH responsiveness, POSS–PDMAEMA micelles could release organic dye absorbed into the organic solution again when the solution was heated to 40 °C or pH value of the solution was adjusted to 4.0. It suggested that POSS–PDMAEMA can be utilized as an interesting “smart” materials for absorption of organic dyes.