Abstract
| - The preparation of temperature-responsive colloidal nanogels with a pH-responsive shell could be achievedby photo-cross-linking of poly(N-isopropylacrylamide) (PNIPAAm) graft terpolymers. The graft terpolymerswere synthesized from NIPAAm, poly(2-vinylpyridine) (P2VP) macromonomers, and a chromophoremonomer based on dimethylmaleimide (DMIAAm). The resulting solutions of nanogel with temperature-responsive core and chemically bounded (P2VP) arms exhibited more stablility upon heating and low pHas compared to the corresponding PNIPAAm nanogels. A large transition of the average hydrodynamicdiameter of the gels could be observed by increasing either the temperature above 32 °C or the pH above5. It was also demonstated that it is possible to obtain a response to one stimulus without interfering withthe other stimulus. Dynamic light scattering (DLS), scanning electron microscopy (SEM), differentialscanning calorimetry (DSC), and nuclear magnetic resonance (NMR) were used for characterization of thecore−shell nanogels.
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