Temperature and pH Dual-Responsive Polyhedral Oligomeric Silsesquioxane/Poly[2-(dimethyl amino)-ethyl methacrylate]-bPoly(N-isopropylacrylamide) Hybrid Materials Synthesized via RAFT Polymerization and Thiol-Ene Reaction: Potential Candidates for Absorption of Organic Dyes

The temperature and pH dual-responsive polyhedral oligomeric silsesquioxane/poly[2-(dimethylamino)-ethyl methacrylate]-b-poly(N-isopropylacrylamide) hybrid materials (POSS/PDMAEMA-b-PNIPAM) were synthesized via combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and thiol-ene "Click Chemistry." Their structures and self-assembly behaviors were characterized by 1HNMR, TEM, UV-vis absorbance and DLS measurements. POSS/PDMAEMA-b-PNIPAM could self-assemble into thermo- and pH-sensitive micelles with the POSS heads forming as a core and the PDMAEMA-b-PNIPAM chains as a corona. Hydrophobic dyes could be encapsulated in the micelles, so it can be used to absorb dyes. It was found that POSS/PDMAEMA-b-PNIPAM aqueous solution (5 mg/mL, 2 mL) could rapidly remove 98% of methyl red and 90% of diphenylthiocarbazone in petroleum ether with the initial concentrations of 50 mg/L (2 mL). In view of the good adsorption efficiency of POSS/PDMAEMA-b-PNIPAM hybrid materials, they will be a potential candidate for absorption of organic dyes.