Fabrication of functional polymer-coated nanoparticles and their applications in sensor and compatibilizer

Abstract

Polymer-coated nanoparticles have received considerable attention because of their potential applica-tions in electronic and optical devices, surfactants, and catalysis. The inorganic core can provide unique opti-cal, electrical, magnetic, and catalytic properties, and the polymeric coating can stabilize the nanoparticles by inhibiting their aggregation. These polymers can be independently designed to precisely control the interaction between the nanoparticles and the outside medium. Thus, the right polymeric coating allows the polymer-coated nanoparticles to interact favorably with the polymer and the fluid matrix to produce new morphol-ogies and enhances their bulk properties, e.g., the thermal, electrical and mechanical properties of the compo-sites. If the nanoparticles are coated with stimuli-responsive polymer, it can be used as sensor which shows different properties according to external stimuli. To prove this, fluorescent and pH-responsive PyMMP-b-P2VP diblock copolymers were designed and synthesized on the CdSe/ZnS QDs using the facile “grafting-from” method via RAFT polymerization. Red and blue colors are emitted from the CdSe/ZnS cores and pyrene shells, respectively, and the FRET efficiency between these two distinguishable chromophores is gov-erned by the interspacing between them, which can easily be controlled through manipulation of the confor-mational features of the P2VP chains that respond to changes in pH. Our approach used diblock copolymer-coated QDs and provided a simple and robust route for the construction of a ratiometric pH sensor, which can be easily extended to other types of sensors for the detection of alternate stimuli, such as temperature and light, using appropriate, responsive polymers. And when polymer-coated nanoparticles are introduced polymeric system, such as binary polymer blends, it can interact favorably with the outside polymer medium, stabilizing the system. Using this property, we aim to obtain stabilized co-conti...