Multistimuli Responsive Organosilica Hybrid Nanoparticles Based on Poly(ether amine)

We demonstrated here novel multistimuli responsive organosilica hybrid nanopaticles (SiO 1.5 -gPEA NPs) based on graft poly(ether amine)s (gPEAs). Poly(ether amine)s comprised of trimethoxysilyl moieties (TMS-gPEAs) were synthesized via nucleophilic substitution/ring-opening reaction of commercial poly(propylene glycol) diglycidyl ether, Jeffamine L100 and 2-aminoethanolthiol, followed by introducing trimethoxysilyl moieties (TMS) into side-chain via “thiol−ene” reaction. The obtained TMS-gPEAs could be dispersed directly in water to form the core-cross-linked hybrid nanoparticles (SiO 1.5 -gPEA NPs) with diameter of about 20 nm, which was revealed by TEM and DLS. These obtained SiO 1.5 -gPEA NPs in aqueous solution were responsive to temperature, pH and ionic strength with tunable cloud point (CP). Simultaneously, SiO 1.5 -gPEA NPs could encapsulate hydrophobic guest molecule Nile Red in water. It is interesting that SiO 1.5 -gPEA NPs can sequester the hydrophilic dyes selectively: SiO 1.5 -gPEA11 NPs could transfer only Rose Bengal (RB) reversibly from the aqueous mixture of RB and Rhodamine 6G (R6G) to toluene, which was controlled by temperature. These characteristics will give SiO 1.5 -gPEAs potential in smart separation.