(284h) Engineering Polymer-Nanoparticle Systems Towards Sustainable Devices and Sensors
First, CNCs were used to induce long-range order in a semiconducting polymer, poly[3-(potassium-4-butanoate) thiophene-2,5-diyl] (PPBT). When mixed with CNCs, PPBT was incorporated into the liquid crystal âtemplateâ to form ordered structures. The ÏâÏ interactions between polymer chains, which contribute considerably to the energetics of the semiconducting system, were directly influenced by the presence and packing of the liquid crystal phase. The results of this study led to exploring a temperature âswitchableâ liquid crystal system. The thermoresponsive polymer, poly(N-isopropylacrylamide) (PNIPAM) was grafted from the surface of CNCs via surface-initiated atom transfer radical polymerization (SI-ATRP). These PNIPAM-modified particles formed a liquid crystal phase at room temperature but when brought above the lower critical solution temperature of PNIPAM (~32Â°C), the sample became dark under crossed polarizers and the liquid crystal was switched âoffâ. This âswitchableâ liquid crystal system could provide a basis for a sustainable sensor in smart packaging or other applications that require a response to temperature.