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Herein, we reported the first highly stable β-CD-based humidity sensor without the need of pre-functionalization of the QCM transducer surface. Two partially benzylated β-cyclodextrins (β-CDBn, x = 7 and 14) were prepared via a green and one-pot synthesis in aqueous media. The macromolecular structures were methodically investigated by means of NMR, FT-IR and MALDI-TOF spectroscopies and studied with DFT calculations. XRD analysis and thermal analysis revealed an amorphous morphology with better thermal stability in comparison with pristine β-CD. AFM characterization proved that the obtained water-insoluble cyclodextrin thin films exhibited good solution-processing characteristics and film-forming quality. Contact angle measurements evidenced a systematic increase in the surface hydrophobicity with the benzylation rate. These organic materials were investigated as sensitive membranes for humidity detection based on quartz crystal microbalance technique. The experimental investigation showed that the QCM coated with β-CDBn sensitive layer exhibited good sensing performances within a wide relative humidity range of 11-98% including high sensitivity, good linearity, fast response (15 s), desirable reproducibility and high stability even at high humidity level. [ABSTRACT FROM AUTHOR]

A new anthracene-based polymer containing the isosorbide group in the side chain ( PPVIs-An) has been synthesized via Wittig reaction. The polymer is soluble in common organic solvents and shows good film-forming abilities. The macromolecular structure was characterized by NMR and FT-IR spectroscopies. This organic material was investigated by differential scanning calorimetry and thermogravimetric analysis and showed an amorphous behavior with a T of 48 °C. The surface property of the PPVIs-An film was analyzed by contact angle and by atomic force microscopy. The optical properties of this organic semi-conductor were investigated by UV-Visible absorption and photoluminescence spectroscopies. The polymer exhibits a blue fluorescence in dilute solution and a green emission in thin film. The introduction of the polar isosorbide groups shown to improve the PL intensity, and a quantum yield of 72 % was obtained. The absence of π- π interaction between the chromophore units in polymer thin layer at fundamental electronic state was observed, due to the presence of steric repulsions between anthracene and isosorbide groups. The HOMO-LUMO energy levels were determined by cyclic voltammetry. An ITO/ PPVIs-An/Al single-layer device was elaborated and investigated using current-voltage measurements which show a turn-on voltage of 5.3 V. The conduction mechanism seems to be a space-charge-limited current with exponential trap distribution at high applied bias voltage. The electrical transport properties of this device were studied as a function of frequency (100 Hz-10 MHz) and applied bias in impedance spectroscopy analyses. [ABSTRACT FROM AUTHOR]