Temperature Responsive Solution Partition of Organic–Inorganic Hybrid Poly(N‐isopropylacrylamide)‐Coated Mesoporous Silica Nanospheres

A series of poly(N-isopropylacrylamide)-coated mesoporous silica nanoparticle materials (PNiPAm-MSNs) has been synthesized by a surface-initiated living radical polymerization with a reversible addition-fragmentation chain transfer (RAFT) reaction. The structure and the degree of polymerization of the PNiPAm-MSNs has been characterized by a variety of techniques, including nitrogen sorption analysis, {sup 29}Si and {sup 13}C solid-state NMR spectroscopy, transmission electron microscopy (TEM), and powder X-ray diffraction (XRD). The thermally induced changes of the surface properties of these polymer-coated core-shell nanoparticles have been determined by examining their partition activities in a biphasic solution (water/toluene) at different temperatures.

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