Simple and promising approaches for developing high‐performance Fe3+ sensors were proposed. Polyvinyl chloride (PVC) membrane containing pyrene as a fluorescent indicator was prepared via solvent‐cast method. Upon immersion into 1.0 mM Fe3+ solution, the fluorescence emission of the membrane decreased with the ratio of fluorescence intensities before and after (F0/F) immersion of 1.25. The sensitivity enhancement was achieved through the introduction of polystyrene (PS) onto PVC and the introduction of porous structures. Polyvinyl chloride‐graft‐polystyrene copolymers (PVC‐g‐PS) were synthesized via Atom Transfer Radical Polymerization using PVC as macroinitiator. The grafting percentages of PS on PVC calculated from Nuclear Magnetic Resonance Spectroscopy were 17 and 41. The membrane prepared from low molecular weight copolymer showed higher sensing ability than that from PVC with the F0/F value of 1.39. The increase in PS chain length did not significantly affect the fluorescence quenching. A Stern–Volmer quenching relationship was found with Ksv of 3.96 × 102 M−1. The effect of porous structures on fluorescence quenching was studied by introducing Triton X‐100 as a porogen to PVC/pyrene solution. Attenuated total reflection Fourier transform infrared spectroscopy and Scanning Electron Microscopy analyses confirmed a complete removal of Triton X‐100 after 3 days of immersion in water. The porous membrane demonstrated an enhanced sensing performance with the F0/F value of 1.46. PVC‐g‐PS/pyrene membrane exhibited highly sensitive and selective responses toward Fe3+ over Cu2+, Mg2+, Co2+, Zn2+, Ni2+, and Ag+. In addition, a good reversibility after five cycles of quenching and regeneration was obtained. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41759.

Electrospun fibers for ferric ion (Fe 31 ) detection were prepared from solutions of poly(methyl methacrylate) (PMMA), poly(vinyl chloride-co-vinyl acetate-co-vinyl alcohol) ((90 : 4 : 6), PVC terpolymer), and pyrene. The effects of PVC terpolymer content (0,10,20, 30, and 40% by weight of PMMA) and electrospinning conditions on fiber size and morphology were studied using scanning electron microscopy. Uniform fibers were obtained from all compositions, and fiber sizes slightly increased with PVC terpolymer content. At 40% PVC, fiber breakage and pyrene clusters were observed. The suitable pyrene content in electrospun fibers was found to be 20%. The ratio of fluorescence intensities of fibers with 30% PVC and 20% pyrene before and after (F 0 /F) immersion in 1.0 mM Fe 31 solution was 1.36.

Simple approaches for developing sensitive fluorescence sensors for 2,4-dinitrotoluene (DNT) detection were reported. Pyrene-doped poly(methyl methacrylate) (PMMA) and poly(vinyl chloride-co-vinyl acetate-co-vinyl alcohol) (PVC terpolymer) fibres, polystyrene (PS) fibres, and poly(styrene-co-methyl methacrylate) (PS-co-PMMA) fibres were prepared via electrospinning technique. Fibre morphology was studied using scanning electron microscopy. Sensing performance towards DNT was monitored through fluorescence emission of pyrene. The time dependence of quenching was observed for all fibres. Polymer matrix was found to affect DNT sensing, where PS fibres and PS-co-PMMA fibres showed slightly higher quenching efficiencies than PMMA-PVC terpolymer fibres. Enhanced quenching efficiency was achieved through introduction of porosity using poly(ethylene glycol)-400 (PEG) as a porogen to PMMA-PVC terpolymer fibres. The effect of porosity on sensing performance was further explored in pyrene-doped PS-co-PMMA membrane. Porous membrane prepared from a solution with PS-co-PMMA to PEG ratio of 1:1 provided higher sensing performance towards DNT than dense PS-co-PMMA membrane, possibly resulting from the increased surface area.