Multifunctional electrospun (ES) nanofibers are successfully prepared from blends of poly((N‐isopropylacrylamide)‐co‐(N‐hydroxymethylacrylamide)) (poly(NIPAAm‐co‐NMA)) with NO(g)‐responsive 1,2‐diaminoanthraquinone (DAQ). Different compositions of poly(NIPAAm‐co‐NMA) are synthesized by free radical polymerization. The NMA content significantly affects the stability of the ES nanofibers in water and the NO(g) detection due to a change of the hydrophilic/hydrophobic characteristics. In addition, the fibers exhibit a significant volume (or hydrophilic/hydrophobic) change during the heating and cooling cycle between 25 and 50 °C, attributed to the lower critical solution temperature (LCST) characteristic of the thermoresponsive NIPAAm moiety. On the other hand, a distinct on/off switching of the optical absorption spectra and high color contrast on detecting the NO(g) are observed using the ES nanofibers of poly(NIPAAm‐co‐NMA)/DAQ blends. The high surface/volume of ES fibers enhance the sensitivity and responsive speed, compared with that of drop‐cast film. The above studies suggest that the prepared multifunctional ES nanofibers have potential applications in environmentally sensing devices.

Novel multifunctional fluorescent electrospun (ES) nanofibers were prepared from random copolymers of poly{2-{2-hydroxyl-4-[5-(acryloxy)hexyloxy]phenyl}benzoxazole}-co-(N-isopropylacrylamide)-co-(stearyl acrylate)} (poly(HPBO-co-NIPAAm-co-SA)) using free-radical polymerization, followed by electrospinning.The moieties of HPBO, NIPAAm, and SA were designed to exhibit zinc ion (Zn 2+ ) and pH sensing, thermoresponsiveness, and physical cross-linking, respectively. The ES nanofibers prepared from the P4 copolymer (1 : 93 : 6 composition ratio for HPBO/NIPAAm/SA), showed ultrasensitivity to Zn 2+ (as low as 10 À8 M) because of the large blue-shifting of 75 nm of the emission maximum and the 2.5-fold enhancement of the emission intensity. Furthermore, the nanofibers exhibited a substantial volume (or hydrophilic-hydrophobic) change during the heating and cooling cycle between 10 C and 40 C, attributed to the low critical solution temperature of the thermoresponsive NIPAAm moiety. Such temperature-dependent variation of the prepared nanofibers under the presence of Zn 2+ or basic conditions led to a distinct on-off switching of photoluminescence. The high surface-to-volume ratio of the prepared ES nanofibers significantly enhanced their sensitivity compared to that of thin films. These results indicated that the prepared multifunctional ES nanofibers could be potentially used in metal ion, pH, and temperature sensing devices.