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A series of novel block copolymers based on two biodegradable polymers, poly(ε-caprolactone), PCL, and poly(isosorbide), PIS, with PIS fractions 5, 10, and 25 wt%, are studied herein. The aim is to assess the effects of the amorphous PIS phase on the properties of the semicrystalline PCL (majority), in addition to the synthesis strategy. The latter involved the polymerization of caprolactone onto initial PIS of low molar mass, resulting, thus, in gradually shorter PCL blocks when the starting amount of PIS is increased. The structure-property relationship investigation, with an emphasis on molecular mobility and crystallization, involves the following sum of complementary techniques: differential scanning calorimetry, dielectric spectroscopy, polarized optical microscopy and X-ray diffraction. The molecular mobility map for these PCL/PIS and initial PIS is drawn here for the first time. Despite the high glass transition temperature of PIS (

The grafting reaction of β-cyclodextrin-based microcapsules containing neroline onto pure cotton jersey knitted fabric is studied. The influence of the concentrations of microcapsules, citric acid (CA) crosslinking agent and catalyst on the fabric mass gain was studied to determine the optimum operating conditions. For this purpose, an experimental design based on response surface methodology (RSM) was used leading to the development of a predictive statistical model. The optimal grafting conditions were thus determined: 107.6 g ⋅ L−1 for microcapsules concentration, 111.9 g ⋅ L−1 for CA concentration and 50 g ⋅ L−1 for disodium hydrogen phosphate (DHP) catalyst concentration (CAT). Morphology, tensile properties, air permeability and washing fastness of finished textile were studied to evaluate the effectiveness of the optimised grafting process.

Recently, polymer composite material has shown excellent performance in a wide range of technological applications, such as renewable energy, biomedical applications, optoelectronic devices …etc. As the knowledge-base on this emergent material continues to grow, a new kind of hybrid sensors fabricated with semiconducting metal oxides and conducting polymers had been synthesized and had demonstrated high sensing capability for several poisonous gases and chemical warfare agents at room temperature. This research work introduces the synthesis and the characterization of a novel polymer P-DSBT composite consisting of ZnO nanoparticles (P-DSBT/ZNO). The composite films P-DSBT/ZNO are prepared by spin coating technique and then studied using different spectroscopic characterization techniques, i.e., FTIR, XRD, SEM, TEM, AFM and UV–Vis to further investigate on the structure and the morphology of this material. For assessing the P-DSBT/ZNO selectivity, different oxidizing and reducing gases were applied and it was found that the nanocomposite has the best selectivity for methane (CH4). The obtained P-DSBT/ZNO shows a wide sensing range (0–200 ppm) and a very high response magnitude, i.e., relative resistance changes of approximately 40% per 60 ppm of CH4. The key finding of this work is that sensitivity for gas detection is greatly improved by the interaction of ZnO-based hybrid materials at room temperature.

International audience; Two new dumbbell-shaped molecules based on two solubilizing and structuring triazatruxene (TAT) units linked by a central chromophore were synthesized and studied. The central chromophore was an electro-deficient fluorene-malononitrile (FM) unit, that can be functionalized symmetrically on two different positions, giving rise to two positional isomers, called TAT-pFM and TAT-mFM, when the TATs are connected to the 2,7-and 3,6positions, respectively. The two isomers exhibited different electronic conjugation pathways that drastically affect their absorption properties and energy levels. Moreover, while TAT-pFM was organized in a stable 3D mesomorphic structure from room-temperature to the melting, TAT-mFM remained crystalline and decomposed before melting. Finally, despite a lower hole mobility, the TAT-mFM exhibited the highest Power Conversion Efficiency (PCE) of about 2% in organic solar cells. This higher PCE was attributed essentially to the pronounced internal charge transfer band contribution to the charge photogeneration observed in TAT-mFM solar cells.

In this article, we report a combined experimental and theoretical study on the optoelectronic properties of two semi-conducting polymers containing different $\pi $ -conjugated sequences [distyrylphenylene (P-DSP) and distyrylbithiophene (P-DSBT)]. Theoretical calculations were conducted, based on time-dependent density functional theory and Marcus theories, to predict the optical, electronic, and charge transport properties of the studied polymers. These results were compared with the experimental ones measured using UV–vis and photoluminescence (PL) spectroscopies. The P-DSBT polymer shows good absorption with a maximum absorption wavelength of 426 nm and a green emission with a maximum wavelength of 508 nm. Besides, the calculated characteristics showed that P-DSBT has better electron and hole mobilities of $7.9\times 10^{-6}$ cm $^{-2}\,\,\text{V}^{-1}\,\,\text{s}^{-1}$ and $3.4\times 10^{-6}$ cm $^{-2}\,\,\text{V}^{-1}\,\,\text{s}^{-1}$ , respectively. A numerical simulation of ITO/polymer/Al device using the Silvaco Tecad simulator was reported and fitted to the experimental data and the results reveal an excellent overlap with the experimental ones. Moreover, the simulation of ITO/polymer/Alq3/Al bilayer organic light-emitting diode (OLED) has been performed and electrical behavior enhancement was evidenced compared with the monolayer device with a maximum current decrease from 9 to 49 mA, using P-DSBT polymer.

A simple, rapid and green method to develop fluorescent cotton yarns was established. We report the application of fluorescein (FL) into textile support by impregnation method while keeping the original cotton yarn properties for anti-counterfeiting applications. The FL-coated yarns were characterized by Scanning Electron Microscopy, reflectance and fluorescence spectroscopy. The CIE chromaticity diagram showed a yellowish green emission with a weak yellow coloration of cotton fiber. Mechanical characterization of samples shows that the application of fluorescein did not alter significantly the breaking strength and elongation at break of the fibers, even when using resins. In contrast, to resin-free impregnation process the color fastness test demonstrates that the use of resins as binder is required. The obtained results showed that cotton samples release slowly its contents and fluorescein remains more than five washing cycles.

In the past few years, π-conjugated polymers, especially PPV derivatives, have been target of intense studies due to their fascinating properties. In this paper, structural, vibrational and optoelectronic properties of a PPV-type π-conjugated polymer (BPAEt2-PPV) displaying three different stereoisomers: Z-Z, E-E and Z-E have been investigated based on density functional theory (DFT) calculations. Theoretical studies were performed in order to justify the chemical structure and also to predict polymer-structure property relationships. Based on TD-DFT and Marcus theories, we have explored the impact of structural configuration on optoelectronic properties and charge mobility. As a result, E-E structure shows a better absorption with a maximum wavelength λabsmax= 407.52 nm mainly composed by π → π* electronic transitions and a gap energy equal to 3.39 eV. Similarly, all structures shows a blue emission properties with a best maximum wavelength of λemissmax= 439.18 nm for E-E structure. Furthermore, the theoretical results showed that the electron mobility for E-E structure was high as compared with others configurations with an electron intermolecular charge hopping Ket = 8.54 1013. While the better hole transport is found for Z-Z structure with a hole intermolecular charge hopping Kht = 6.21 1013. Finally, a numerical simulation, of an organic light emitting diode device using Silvaco TCAD software has been performed and a good enhanced in electrical properties are obtained for E-E configuration compared to Z-Z and Z-E structures with a turn-on voltage of 6.2 V. Based on these interesting results, we have deduced that all structures could be exploited as an active layer in organic light emitting diode.

An anthracene and carbazole based π-conjugated Schiff base (An2Cb) was characterized to emphasize its optical, dielectric and gas sensing properties. UV–Visible absorption spectrum shows three main maxima at 279, 340 and 420 nm with an optical gap of 2.33 eV determined according to Tauc model. Computational analysis by Time Dependent Density Functional Theory (TD-DFT) was used to obtain a UV–Visible absorption spectrum found in good agreement with the experimental chart. The 3D charge distribution was theoretically determined through B3LYP/6–311 + G* basis set. Current-Voltage characteristics of the device are typical to diode behaviour with a trap controlled space charge limited current transfer mechanism. The AC dynamic electrical transport process was studied in function of temperature. It displays a hopping transport process with a thermal activation energy of 0.88 eV. The device is assimilated to an equivalent electrical circuit based on a resistance Rs in series with a resistance Rp which is parallel to a constant phase element CPE. Gas sensing performance was tested. It shows a selective and reversible oxygen sensor at low concentration at room temperature, and an improvement in its sensitivity was observed with increasing temperature until 333 K.

Poly(2,5-furandicarboxylate)s incorporating aliphatic moieties represent a promising family of polyesters, typically entirely based on renewable resources and with tailored properties, notably degradability. This study aims to go beyond by developing poly(isosorbide 2,5-furandicarboxylate-co-dodecanedioate) copolyesters derived from isosorbide (Is), 2,5-furandicarboxylic acid (FDCA), and 1,12-dodecanedioic acid (DDA), and studying their degradation under environmental conditions, often overlooked, namely seawater conditions. These novel polyesters have been characterized in-depth using ATR-FTIR, 1H, and 13C NMR and XRD spectroscopies and thermal analysis (TGA and DSC). They showed enhanced thermal stability (up to 330 °C), and the glass transition temperature increased with the content of FDCA from ca. 9 to 60 °C. Regarding their (bio)degradation, the enzymatic conditions lead to the highest weight loss compared to simulated seawater conditions, with values matching 27% vs. 3% weight loss after 63 days of incubation, respectively. Copolymerization of biobased FDCA, Is, and DDA represents an optimal approach for shaping the thermal/(bio)degradation behaviors of these novel polyesters.

New soluble semiconducting anthracene-based polyethers (An-BPS and An-TDP) were synthetized via the Williamson polycondensation of 9,10-dichloromethylanthracene with 4,4′-thiodiphenol (TDP) and bisphenol S (BPS), respectively. The polymers were investigated by density functional theory (DFT): the structural and optoelectronic properties, frontier molecular orbitals (HOMO/LUMO), as well as the infrared, absorption and fluorescence spectra were discussed. The polyethers structures were confirmed by NMR and FTIR spectroscopies, revealing good agreements between experimental and theoretical results. Quasi-identical absorption and blue emission properties were obtained for both polymers in dilute solutions, with a higher fluorescence efficiency for An-BPS. The cyclic voltammetry analysis of these electrochemically active materials showed a higher electron affinity for An-BPS and a lower ionization potential for An-TDP. The DFT calculations showed that the HOMO/LUMO frontier energy distributions are confined on the anthracene moiety in An-BPS. However in An-TDP, the LUMO distribution is localized on anthracene group, while the HOMO is on the TDP unit. The electric behaviour of organic light-emitting diodes (OLEDs) based on these macromolecular structures has been investigated via numerical simulation using Silvaco TECAD software. Good electrical properties are estimated, with a low turn on voltages of 3.1 V and 2.9 V for An-TDP and An-BPS, respectively. However, An-BPS showed improved current conductivity, which makes it a good candidate for OLEDs.

This work aims to synthesize and characterize a new semiconducting anthracene-based polymer Poly-Tet-An-Is and its analogue anthracene-free Poly-Tet-Is. The two materials contain the Tetrazole group in the backbone and the Isosorbide group in the side chain. The polymers have been prepared through click chemistry polymerization. The effect of the anthracene group on photophysical and electrochemical proprieties, is investigated. Thermal characterization shows that the two polymers have a good thermal stability up to 330°C. The optical properties of these materials were explored by UV-vis absorption and photoluminescence spectroscopies. The UV-vis absorption spectrum reveals that the presence of anthracene group in the backbone limits the intramolecular interaction in dilute solution and the π-stacking in the thin film by its steric effect. The photoluminescence spectra reveals that the polymer Poly-Tet-Is has a blue emission in dilute solution and thin film. However, the Poly-Tet-An-Is emission shifted from blue to green, going from dilute solution to the thin film, respectively. Density Functional Density (DFT) has been used to evaluate the macromolecular geometry of both polymers and showed a remarkable variation in geometry depending on the incorporation of the anthracene group. An analysis by RDG was carried out on the optimized structures of the two organic materials in order to prove the intarmolecular interactions and its influence on their geometries. The interested photophysical properties of our new materials as well as the presence of the Tetrazole group in the main chain, could be applied in the design of chemical sensors and blue Organic light-emitting diode (OLED).

Poly(1,4-phenylenevinylene) derivative (PPV-C6) based solution was spin-coated onto hydrothermally grown and vertically aligned ZnO nanorods (ZnO NRs).The morphological and the optical properties of the PPV-C6/ZnO NRs hybrid heterojunction have been studied and shown a penetration of PPV-C6into the interspaces between the ZnO NRs with enhanced excitonic dissociation. The current–voltage characteristics in dark and under 395 nm LED illumination have been analyzed. A short-circuit current Jsc of 4691.42 μA/cm2, an open-circuit voltage Voc of 0.46 V giving rise to a responsivity of about 29.32 mA/W have been obtained for the illuminated graphite/PPV-C6/ZnO NRs/Si/EGa-In structure based near UV light sensor showing an enhanced responsivity by a factor of about 200 compared with bare ZnO NRs based one. We have succeeded in the development of low cost near-UV light sensors by simple low temperature hydrothermal method using eco-friendly, low cost and easily fabricated electrodes.

In this paper, a series of fully biobased poly(1,4-cyclohexanedimethanol-co-isosorbide 2,5-furandicarboxylate)s (PCIsFs) copolyesters have been synthesized from dimethyl-2,5-furandicarboxylate (DMFD), isosorbide (IS) and 1,4-cyclohexanedimethanol (CHDM) by melt polycondensation. The structure of prepared polymers was characterized by 1H NMR and FTIR spectroscopies. Differential scanning calorimetry (DSC) results indicated that the crystallizability and melting temperature (Tm) of PCIsFs can be controlled with the increasing content of isosorbide furanoate units into the copolyesters structure, whereas their glass transition temperatures (Tg) showed a beneficial increase ranging from 76.8 °C to 103.5 °C. Wide-Angle X-ray Diffractometry (WAXD) patterns revealed that a small portion of isosorbide units are inserted into the crystals of PCHDMF, resulting in increase of the interplanar distances and crystal defects. A banded spherulitic morphology was observed, while coarsening of spherulites and increase in band distance occurred with increasing isosorbide content. Thermogravimetric analysis (TGA) results showed an excellent thermal stability up to 360 °C for all copolymers.

In this study, a poly (1, 4-phenylenevinylene) derivative (PPV-C 6 ) was synthesized via Gilch polycondensation, and its electrochemical and optical characteristics were determined by cyclic voltammetry analysis, ultraviolet–visible, and photoluminescence spectroscopy. The polymer exhibited semiconductor behavior with an optical band gap of about 2.02 eV. Thin-film hybrid nanocomposites were prepared based on PPV-C 6 with a large range of concentrations of sol–gel synthesized surfactant-free ZnO nanoparticles (n-ZnO). We investigated the photophysical properties of nanocomposites with different weight ratios of n-ZnO. The optical absorption spectra of PPV-C 6 : n-ZnO nanocomposites exhibited moderate variation in terms of the optical band gap energy with respect to the pristine polymer. Photoluminescence spectra indicated that the optimum n-ZnO concentration was about 50 wt% to achieve photoluminescence quenching, which corresponded to the most homogeneous surface and efficient charge transfer due to optimal exciton dissociation. We established good correlations between the investigated properties.

In order to prepare thermally stable isosorbide-derived thermoplastic polyurethane, the synthesis of two new chiral exo–exo configured diols, prepared from isosorbide, and two types of diphenols (bisphenol A and thiodiphenol) was described. The synthesis conditions were optimized under conventional heating and microwave irradiations. To prove their suitability in polymerization, these monomers were successfully polymerized using 4,4′-diphenylmethane diisocyanate (MDI) and hexamethylene diisocyanate (HDI). Both monomers and polymers have been studied by NMR, FT-IR, TGA, DSC; intrinsic viscosity of polymers has also been determined. The results showed the effectiveness of the synthetic strategy proposed; moreover, a dramatic reduction of the reaction time and an important improvement of the monomers yield using microwave irradiation have been demonstrated. The monomers, as well as the polymers, showed excellent thermal stability both in air and nitrogen. It was also shown that the introduction of sulphur in the polyurethane backbone was effective in delaying the onset of degradation as well as the degradation rate.

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 , 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-CDBn7 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.

A linear biobased polyacetal was prepared from the reaction between isosorbide and methylene chloride according a one step procedure. Cyclic polyacetal was obtained using the previous linear polymer as precursor. The respective architectures of both polymers and their chemical compositions were carefully established using 1 H NMR and MALDI-TOF spectroscopies. Their molecular weight characteristics were defined using a triple detection size exclusion chromatography while their thermal characteristics were investigated by the conduction of calorimetric and thermogravimetric experiments. The registering of the thermomechanical properties of each kind of isosorbide-based polyacetal showed that the cyclic polymer was the only one able to show a rubbery plateau. This peculiarity was justified by calculation of the threshold value above which entanglements were possible.

In the present work, poly(ethylene furanoate) (PEF) was synthesized via two-stage melt polycondensation process, using four different catalysts, namely tetrabutyl titanate (TBT), titanium(IV) isopropoxide (TIS), tin(II) 2-ethylhexanoate (TEH) and dibutyltin(IV) oxide (DBTO). In all reactions, 2,5-dimethylfuran-dicarboxylate (DMFD), ethylene glycol (EG) (1:2 molar ratio) and 400 ppm of catalyst were used. The effect of these catalysts on the remelting and decomposition mechanism of PEF was studied. All polyesters were remelted up to three times, and for every melting cycle the intrinsic viscosity (IV) values and the carboxyl end group content were measured. It was found that after every melting, the IV was reduced while the COOH number was increased. Also, all samples have been studied with Fourier Transformed-Infrared Spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. It was found that the molecular weight reduction also affects the thermal properties of the polyesters. The decomposition mechanism of the prepared polyesters was studied using pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS).

In this paper, a novel kind of microcapsules containing 2-ethoxynaphtalene (neroline) was successfully synthesized into polyurethane shells through the interfacial polycondensation of β-cyclodextrin with 4,4’-methylene (bisphenyl isocyanate) (MDI) in direct emulsion. The IR spectroscopy was used, on the one hand to confirm the success of polymerization reaction leading to the polyurethane shell formation, but on the other hand to check the encapsulation efficiency of fragrance that accounts for 40%. Microcapsules’ spherical shape and particle size distributions were revealed by means of optical microscopy, scanning electron microscopy (SEM) observation, and small-angle light scattering measurement. The impregnation of neroline-loaded microcapsules on polyamide knitted fabric was tested as an application method at a yield of around 74%. Adhesion of synthesized microcapsules to textile materials was evaluated through microscopic observations. The durability of the impregnation effect was tested by SEM and UV-visible spectroscopy. Washing fastness test of the impregnated polyamide knitting proved that the loaded microparticles retained their efficiency after more than 35 washing cycles.

This study spotlighted a successful synthesis of a novel series of biobased poly(decamethylene-co-isosorbide 2,5-furandicarboxylate)s (PDIsFs) copolyesters from dimethylfuran-2,5-dicarboxylate (DMFD), isosorbide (Is), and 1,10-decanediol (1,10-DD) by melt polycondensation, using titanium(IV) isopropoxide (TTIP). The chemical structure and composition of prepared polymers were confirmed in detail by H NMR and FTIR spectroscopies. Satisfactory weight-average molecular weights (M ) in the 55,300-84,500 g/mol range and random microstructures were obtained for PDIsFs. It was shown that Is unit incorporation into the copolyesters molecular chains was dramatically effective in increasing the glass transition temperatures (T ) and in delaying the onset decomposition temperatures of PDIsFs. Hence, an excellent improvement of the thermal stability exceeding 405 °C for all copolymers was obtained. In addition, the degradation behavior in soil as well as the mechanical properties of PDIsFs were duly investigated in detail. The biodegradation rate of the copolyesters depended on the comonomer ratio. Rotational rheometry characterization of polymer melts revealed prevailing viscous properties for all formulations, whereas the presence of isosorbide favored a Newtonian behavior. Oxygen induction time (OIT) measurements by chemiluminescence (CL) demonstrated that isosorbide incorporation also dramatically increases polymer thermo-oxidative stability. Taking advantage of their features, PDIsFs have the potential to serve as promising and innovative biobased polymers for practical applications such as ecofriendly and sustainable plastic packaging.

International audience

Tow isosorbide containing poly(phenylene vinylene-arylene vinylene)s have been synthesized via Wittig polycondensation: PPVIs - Carb (arylene: carbazole) and PPVIs - Naph (arylene: naphtalene). The macromolecular structures were characterized by NMR and FTIR spectroscopies. The polymers are soluble in common organic solvents and show good film-forming abilities thanks to the presence of the polar isosorbide side groups. These organic materials showed an amorphous behavior. A higher polarity of the surface was obtained for PPVIs - Naph . The both polymer films are photoluminescent and exhibit an optical gap of 2.3 eV. The carbazole-based polymer emits in yellow-green while a green-yellow emission was obtained in the naphtalene conatainig polymer with higher fluorescence quantum efficiency. The HOMO/LUMO energy levels were determined by cyclic voltammetry and showed higher ionization potential and electronic affinity for PPVIs - Carb . The study of the ITO/polymer thin film/Al devices showed a space-charge limited current transport mechanism with charge carrier mobility in order of 10 −8 cm 2 V −1 s −1 .

An impedimetric sensor based on a new semi-conducting rotaxane has been described for detection of toxic cations. The rotaxane, consists on a π-conjugated material encapsulated into β-cyclodextrin (β-CD); it has been synthesized via the Williamson reaction under microwaves irradiation. The supramolecular structure of the compound was confirmed by NMR and FT-IR spectroscopies. A thin solid film of the rotaxane was deposited by spin-coating to develop a new electrochemical sensor. The morphological properties of the organic membrane were evaluated using contact angle measurements and atomic force microscopy. The gold/rotaxane/solution interfaces were investigated by electrochemical impedance spectroscopy and the obtained data were fitted using an equivalent electrical circuit. The response of the gold/rotaxane membrane towards Hg2+, Cu2+ and Pb2+ cations was studied and the results showed a good sensitivity to the mercury cations.

International audience; 104 MHz surface acoustic wave (SAW) sensors functionalized with new anthracene derivates were designed for the detection of lead ions (Pb2+) in liquid media. On the basis on quantum chemical calculations, three anthracene molecules have been synthetized and tested: 4-(9-anthrylmethoxy) benzyl[4-(9-anthrylmethoxy)phenyl]sulfone (BPS-AN); 9-{[4-({[4-(9 anthrylmethoxy) phenyl]sulfanyl}methyl)]methyl] anthracene (TDP-AN) and 2,2-bis(4 anthracenylmethoxy-1,1′-biphenyl (BP-AN). Gravimetric results indicate that the affinity of BPS-AN towards Pb2+ ions is superior to that of TDP-AN and BP-AN, confirming thus the computational approach. The designed BPS-AN SAW sensor has a sensitivity of [7.2 ± 4.6]×108 [°/M], a limit of detection (LOD) of 22 pM, and displayed very high affinity to lead ions with an apparent dissociation constant Kd of order of (1.1 ± 2.7) × 10−10. Selectivity was investigated by both gravimetry and DFT calculation. Results indicate that the designed sensor is more sensitive to lead cations than copper and mercury ones. A tetrabutylphosphonium (TBP) lactate ionic liquid (IL) solution was used to regenerate the SAW sensor, permitting its further reuse a dozen times without degrading the BPS-AN recognition layer.

The preparation of polyurethane bio-based microcapsules containing the neroline fragrance aimed at cosmetotextile applications was investigated. The polyurethane shell material was synthesized by interfacial polycondensation using isosorbide and hexane diisocyanate as monomers. Chemical characterization by means of IR-ATR and TGA confirmed the formation of a polyurethane wall and the fragrance encapsulation up to 73% of the dry microcapsules. The physicochemical characterization of neroline-loaded microcapsules was carried out, including thermal properties, size distribution, morphology and zeta potential. The spherical microcapsules of size ranging between 2 μm and 100 μm had a rough external surface. Their thermal stability up to 260 °C was favorable regarding their application to deposition onto textile fibers. According to their IsoElectrical Point of 5.38, these microparticles were anionic at neutral pH. An isosorbide-based cationic surfactant has been adsorbed at the surface of the microcapsules for charge reversal into cationic and stronger binding to negatively charged cotton fabric. Besides, neroline-loaded microcapsules were fixed on pure cotton fabric by an impregnation technique. The reality and durability of the textile treatment were assessed by SEM and Gas Chromatography analysis. The cotton knitted fabric treated with fragrant microcapsules progressively released its microcapsule content; significant amount of residual neroline remained until 40 washing cycles.

International audience; This study aims to synthesize and characterize a new semi-conducting 2,7-distyrylcarbazole-based molecule (M1) and its Schiff-base analog (M2). Those two molecules were synthesized via Wittig-Horner and diamine condensation reactions, respectively. The effects of replacing the vinylene (single bondCHdouble bondCHsingle bond) linkage between carbazole donor unit and anthracene acceptor unit in molecule M1 by an azomethine (single bondCHdouble bondNsingle bond) bridge in molecule M2 on physicochemical and electrical properties are reported in this work. Thermal characterization shows a semi-crystalline morphology in solid state for the two organic materials and a good thermal stability up to 370 °C in the case of M2.The observed non-fluorescence character of the Schiff-base molecule has been related to the photo-induced electron transfer (PET) process from the imine receptor moiety to the anthracene fluorophore unit. The effect of the addition of trifluoroacetic acid (TFA) on optical properties of the Schiff base molecule revealed a significant blue shift of the absorption spectrum and a turn-on of the fluorescence as well as visual changes. Computational analyses by Density Functional Theory (DFT) and time-dependent (TD-DFT) were then used to obtain conformation and the energy distributions of the molecular orbitals of the two compounds. The electrochemical behaviors were investigated by cyclic voltammetry and showed a reduction of the band gap of M2 as compared to M1 du to the electron-withdrawing effect the azomethine (–CHdouble bondN–) bond. Finally, the charge-carrier mobility of the two compounds were extracted from single-layer diodes in the space-charge limited current regime (SCLC) and organic field effect transistors (OFETs) demonstrating lower hole mobilities in the case of M2 based thin film devices. The hole effective mobility of M2 (measured by SCLC) was one order of magnitude higher after exposition to trifluoricacetic acid vapors than in neutral films.

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 g 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.

We have investigated the influence of side-chain size on the optical and charge transport behavior of thin layers of new conjugated polymers based on separated PPV-type chromophores (P1, P2 and P3). The polymers are soluble in common organic solvents. The optical properties of these materials were investigated by UV–Vis absorption and PL spectroscopy. In thin solid films, the polymers show side-group dependent optical behavior; the PL spectra of polymers P2 and P3 showed a blue emission, whereas a green emission was observed for the polymer P1. The optical gaps of these thin layers have been estimated to be 2.93, 2.96 and 2.98 eV for P1, P2 and P3, respectively. The optical study showed a stronger π–π interaction in the P1 film. The electrical properties of ITO/PPV derivative/Al diodes base on these PPV derivatives were investigated by the current/tension characteristics and modeled by the current space-charge-limited (SCLC) mechanism; a higher mobility was obtained in the P2 thin layer. The morphology of the polymer films was studied and correlated to the optical and electrical properties.

This study is an investigation about the effect of chemical modification on the morphological, optical and electrical properties of semiconducting organic thin films. Two confined poly(p-phenylene vinylene) (PPV)-type polymers containing different spacer groups were studied: P1 has an isopropylidene spacer group and P2 with hexafluoroisopropylidene spacer. The UV–Vis absorption and PL analysis showed a stronger π–π interaction in the P1 film; in P2, the π-stacking is limited by the introduction of a bulky trifluoromethyl (CF3) groups on the spacer units. The P2 exhibits a better film quality as illustrated by the atomic force microscopy. The HOMO and LUMO energy levels and electrochemical band gap of the polymers were determinate by the cyclic voltammetry. The electrical properties of ITO/PPV derivative/Al diodes were investigated by means of current–voltage and show a space-charge-limited current conduction mechanism with higher mobility in the P2 thin layer. The impedance spectra of the devices can be discussed in terms of an equivalent circuit model designed as a parallel resistance (R p) and capacitance (C p) network in series with a resistance.

An original polythiophene derivative was characterized to develop the optoelectronic properties of sulfur-containing π-conjugated polymer. The optical properties of the polymer were investigated by UV–visible absorption spectroscopy and atomic force microscopy. Investigations of the electrical characteristics of polymer diodes are reported. We present current–voltage characteristics and impedance spectroscopy measurements performed on partially sulfur-containing thin films in sandwich structure ITO/sulfur-containing polymer/Al. The conduction mechanisms in these layers are identified to be a space-charge-limited current. The AC electrical transport of the sulfur-containing polymer is studied as a function of frequency (100 Hz–10 MHz) and temperature in impedance spectroscopy analyses. We interpreted Cole–Cole plots in terms of the equivalent circuit model as a single parallel resistance and a capacitance network in series with a relatively small resistance. The evolution of the electrical parameters deduced from fitting of the experimental data is discussed.