Optical and Swelling Stimuli-Response of Functional Hybrid Nanogels: Feasible Route to Achieve Tunable Smart Core@Shell Plasmonic@Polymer Nanomaterials

This work focuses on achieving the modulation of optical and swelling properties of nanomaterials based on the self-assembly of thermostimuli polymers around metallic nanoparticles (NPs) for the obtention of functional plasmonic-polymer core/shell nanohybrids. Moreover, an important effort is made for understanding the role of the polymer assembly, molecule interactions, and contributing effect of each nanohybrid's single component (i.e., polymer and NP) in the final temperature-tune optical properties. In this regard, a twostep route for building-up uniform core/shell hybrid nanogels with tunable thermoresponsive and plasmonic properties is considered as the key vehicle to get a better knowledge of the processes governing the synthesis, behavior, and properties of these materials. These plasmonic nanohybrids are made of gold NPs coated with poly(2-(2-methoxyethoxy)ethyl methacrylate) P(MEO(2)MA) nanogels with tunable shell thickness by surfactant (SDS) participation. Thereby, this controlled methodology was probed with spherical AuNPs of 22, 58, and 101 nm diameters, and the hybrid NPs showed size change at the temperature induced volume phase transition (VPTT) of the polymer shell and a red shift of the Localized Surface Plasmon Resonance (LSPR) maximum with increasing temperature. This approach paves the way to new strategies of design and research of temperature induced tunable optically active nanostructures (smart nanomaterials).