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  • F. Abbassi, M. Mbarek, D. Kreher, et K. Alimi, « Synthesis and characterization of a copolymer involving PVK and MEH-PPV for organic electronic devices », Journal of Physics and Chemistry of Solids, vol. 103, p. 142-146.
    Résumé : A statistic copolymer denoted (PVK)x-(MEH-PPV)y containing poly(N-vinylcarbazole) (PVK) as well as poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) building blocks was prepared by chemical oxidative way. Correlations structure-properties of the synthesized copolymer were investigated by using different experimental analyses (IR, XRD, ATG, optical absorption, PL and PLRT) combined with theoretical calculations (DFT). The new copolymer exhibits interesting properties compared to PVK and MEH-PPV homopolymers taken separately. The resulting copolymer has improved thermal stability and it exhibits original optical properties compared to the PVK and MEH-PPV ones as well as its reveled charge transfer process and the continuous donor acceptor existence. All these experimental and theoretical analysis argue the originality of this new material which could then be exploited in optoelectronics.
    Mots-clés : A. Polymers, B. Chemical synthesis, C. Ab initio calculations, C. Optical properties, POLE 4, POLYMERES.

  • R. Albigès, P. Klein, S. Roi, F. Stoffelbach, C. Creton, L. Bouteiller, et J. Rieger, « Water-based acrylic coatings reinforced by PISA-derived fibers », Polymer Chemistry.
    Résumé : Polymerization-induced self-assembly (PISA) is an efficient approach to synthesize self-assembled core–shell nanofibers in water, made of amphiphilic block copolymers. We demonstrate here for the first time that such anisotropic and high Tg nanofibers can be used as reinforcing fillers for water-based acrylic materials. This strategy opens the way for strong all-organic aqueous coatings.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 407.3 ko (source)

  • M. Chenal, C. Véchambre, J. - M. Chenal, L. Chazeau, V. Humblot, L. Bouteiller, C. Creton, et J. Rieger, « Mechanical properties of nanostructured films with an ultralow volume fraction of hard phase », Polymer, vol. 109, p. 187-196.
    Résumé : We demonstrate in this paper how polymerization induced self-assembly (PISA) using RAFT can be used to synthesize very asymmetric but monodisperse poly(acrylic acid)-b-poly(n-butyl acrylate) block copolymers, PAA-b-PBA, with a short PAA block and a long PBA block. In the course of the surfactant-free emulsion polymerization, core-shell particles form in water, with the short hydrophilic block located at the water-particle interface, and the long hydrophobic block constituting the particle core. Drying at room temperature creates films possessing an out of equilibrium structure, where the glassy PAA block generates a percolating network of shells. When deformed in uniaxial elongation, these films combine a high stiffness in small strains (considering the low volume fraction of PAA, of only 3 wt%), a yield stress and a significant extensibility before failure. The modulus, yield stress and extensibility can be tuned by modifying the composition of the latex serum with cations or positively charged low molar mass polymers, or by changing the copolymer composition. Of particular interest was the synthesis by PISA of particles of triblock copolymer PAA-b-PBA-b-PS. The out of equilibrium structure obtained had a very interesting combination of high stiffness, extensibility and high fracture toughness.
    Mots-clés : Core-shell latexes, Film, Mechanical properties, Nanostructure, POLE 4, POLYMERES, RAFT polymerization.

  • M. Dréan, A. Debuigne, C. Goncalves, C. Jérôme, P. Midoux, J. Rieger, et P. Guégan, « Use of Primary and Secondary Polyvinylamines for Efficient Gene Transfection », Biomacromolecules, vol. 18, nᵒ 2, p. 440-451.
    Résumé : Gene transfection with polymeric carrier remains a challenge; particularly, high transfection levels combined with low toxicity are hard to achieve. We herein revisit polyvinylamines, an old and neglected family of cationic polymers. They can be readily obtained by controlled hydrolysis of polyvinylamides prepared through (controlled) radical polymerization. A series of tailor-made and well-defined polyvinylamines bearing primary amino groups, and poly(N-methylvinylamine) bearing secondary amines, were evaluated for the transfection of cells with pDNA as a function of their molar mass, molar mass distribution, and degree of deacetylation. Unexpected high transfection levels, in combination with low cytotoxicity were recorded for both series. Surprisingly, a great impact of the molar mass was observed for the primary amine polyvinylamine series, whereas the results were mostly independent of molar mass or dispersity for the polymer bearing secondary amine. It was further established that a certain percentage of acetamide groups increased the transfection level, while maintaining low cytotoxicity. These results highlight for the first time the real potential of polyvinylamines as gene carriers, and make these polymers very attractive for further development in gene therapy.
    Mots-clés : POLE 4, POLYMERES.

  • M. Fumagalli, K. Belal, H. Guo, F. Stoffelbach, G. Cooke, A. Marcellan, P. Woisel, et D. Hourdet, « Supramolecular polymer hydrogels induced by host–guest interactions with di-[cyclobis(paraquat-p-phenylene)] cross-linkers: from molecular complexation to viscoelastic properties », Soft Matter, vol. 13, nᵒ 31, p. 5269-5282.
    Résumé : Supramolecular polymer networks have been designed on the basis of a π-electron donor/acceptor complex: naphthalene (N)/cyclobis(paraquat-p-phenylene) (CBPQT4+ = B). For this purpose, a copolymer of N,N-dimethylacrylamide P(DMA-N1), lightly decorated with 1 mol% of naphthalene pendant groups, has been studied in semi-dilute un-entangled solution in the presence of di-CBPQT4+ (BB) crosslinker type molecules. While calorimetric experiments demonstrate the quantitative binding between N and B groups up to 60 °C, the introduction of BB crosslinkers into the polymer solution gives rise to gel formation above the overlap concentration. From a comprehensive investigation of viscoelastic properties, performed at different concentrations, host/guest stoichiometric ratios and temperatures, the supramolecular hydrogels are shown to follow a Maxwellian behavior with a strong correlation of the plateau modulus and the relaxation time with the effective amount of interchain cross-linkers and their dissociation dynamics, respectively. The calculation of the dissociation rate constant of the supramolecular complex, by extrapolation of the relaxation time of the network back to the beginning of the gel regime, is discussed in the framework of theoretical and experimental works on associating polymers.
    Mots-clés : POLE 4, POLYMERES.
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  • C. Gonçalves, J. - P. Gomez, W. Même, B. Rasolonjatovo, D. Gosset, S. Nedellec, P. Hulin, C. Huin, T. Le Gall, T. Montier, P. Lehn, C. Pichon, P. Guégan, H. Cheradame, et P. Midoux, « Curcumin/poly(2-methyl-2-oxazoline-b-tetrahydrofuran-b-2-methyl-2-oxazoline) formulation: An improved penetration and biological effect of curcumin in F508del-CFTR cell lines », European Journal of Pharmaceutics and Biopharmaceutics, vol. 117, p. 168-181.
    Résumé : Neutral amphiphilic triblock ABA copolymers are of great interest to solubilize hydrophobic drugs. We reported that a triblock ABA copolymer consisting of methyl-2-oxazoline (MeOx) and tetrahydrofuran (THF) (MeOx6-THF19-MeOx6) (TBCP2) can solubilize curcumin (Cur) a very hydrophobic molecule exhibiting multiple therapeutic effects but whose insolubility and low stability in water is a major drawback for clinical applications. Here, we provide evidences by flow cytometry and confocal microscopy that Cur penetration in normal and ΔF508-CFTR human airway epithelial cell lines is facilitated by TBCP2. When used on ΔF508-CFTR cell lines, the Cur/TBCP2 formulation promotes the restoration of the expression of the CFTR protein in the plasma membrane. Furthermore, patch-clamp and MQAE fluorescence experiments show that this effect is associated with a correction of a Cl− selective current at the membrane surface of F508del-CFTR cells. The results show the great potential of the neutral amphiphilic triblock copolymer MeOx6-THF19-MeOx6 as carrier for curcumin in a Cystic Fibrosis context. We anticipate that other MeOxn-THFm-MeOxn copolymers could have similar behaviours for other highly insoluble therapeutic drugs or cosmetic active ingredients.
    Mots-clés : Amphiphilic polymer, CFTR, Curcumin, Cystic fibrosis, POLE 4, POLYMERES, Triblock copolymer.

  • L. Hassouna, N. Illy, et P. Guégan, « Phosphazene/triisobutylaluminum-promoted anionic ring-opening polymerization of 1,2-epoxybutane initiated by secondary carbamates », Polymer Chemistry, vol. 8, nᵒ 27, p. 4005-4013.
    Résumé : Attempts to use a carbamate-phosphazene base as the initiating system for the polymerization of 1,2-epoxybutane was unsuccessful. As a matter of fact, carbamate deprotonation by phosphazene bases led to their fast decomposition generating alkoxide anions which initiate the polymerization rather than carbamate anions. Conversely, in the presence of triisobutylaluminum – a Lewis acid – the in situ generation of an anionic initiator X− obtained by the deprotonation of the tBuP4 phosphazene base was tested as a possible way to initiate the polymerization of 1,2-epoxybutane. Particular attention was given to the detection of eventual transfer or side-reactions according to the carbamate:triisobutylaluminum:phosphazene base ratio, to the solvent dielectric constant and to the number of PN– units in the phosphazene base. The reaction was perfor

    med with a stoichiometric ratio (1:1:1) of carbamate:triisobutylaluminum:tBuP2, which gave the best results. Under these conditions, the initiation of the polymerization by the carbamate anion was quantitative; no transfer reactions have been observed and the polymerization proceeded in a controlled manner to afford amide end-capped poly(butylene oxide) with a narrow molar mass distribution and expected molar masses.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 1.4 Mo (source)

  • K. J. Lee, Y. Xiao, J. H. Woo, E. Kim, D. Kreher, A. - J. Attias, F. Mathevet, J. - C. Ribierre, J. W. Wu, et P. André, « Charge-transfer dynamics and nonlocal dielectric permittivity tuned with metamaterial structures as solvent analogues », Nature Materials, vol. advance online publication.
    Résumé : Charge transfer (CT) is a fundamental and ubiquitous mechanism in biology, physics and chemistry. Here, we evidence that CT dynamics can be altered by multi-layered hyperbolic metamaterial (HMM) substrates. Taking triphenylene:perylene diimide dyad supramolecular self-assemblies as a model system, we reveal longer-lived CT states in the presence of HMM structures, with both charge separation and recombination characteristic times increased by factors of 2.4 and 1.7—that is, relative variations of 140 and 73%, respectively. To rationalize these experimental results in terms of driving force, we successfully introduce image dipole interactions in Marcus theory. The non-local effect herein demonstrated is directly linked to the number of metal–dielectric pairs, can be formalized in the dielectric permittivity, and is presented as a solid analogue to local solvent polarity effects. This model and extra PH3T:PC60BM results show the generality of this non-local phenomenon and that a wide range of kinetic tailoring opportunities can arise from substrate engineering. This work paves the way toward the design of artificial substrates to control CT dynamics of interest for applications in optoelectronics and chemistry.
    Mots-clés : Metamaterials, POLE 4, POLYMERES, Structural properties, Ultrafast photonics.

  • A. Pontes da Costa, D. R. Nunes, M. Tharaud, J. Oble, G. Poli, et J. Rieger, « Palladium(0) Nanoparticles Embedded in Core–shell Nanogels as Recoverable Catalysts for the Mizoroki–Heck Reaction », ChemCatChem, vol. 9, nᵒ 12, p. 2167-2175.
    Résumé : Core–shell nanogels are attractive stabilizers and supports for catalytically active metallic nanoparticles. Herein, we present the synthesis and the characterization of a nanostructured well-defined core–shell nanogel with the ability to stabilize Pd0 nanoparticles in its core. This hybrid nanogel displays a remarkable stability in both the solid state and in solution. This feature allowed its successful application as a catalyst for the Mizoroki–Heck reaction between n-butyl acrylate and a series of bromo- and iodoarenes. The yields spanned from good to excellent, and catalyst recycling could be achieved up to three times without a significant activity loss. Three-phase tests indicated that the hybrid nanogel acts as a Pd0 nanoreservoir. The catalysis proceeds in a quasihomogeneous fashion as part of the catalytic activity occurs outside the nanogel, which explains the observed limited recyclability.
    Mots-clés : C−C coupling, immobilization, Palladium, POLE 1, POLE 4, POLYMERES, RAFT polymerization, ROCS, supported catalysts.
    Pièce jointe Full Text PDF 1.5 Mo (source)

  • B. Rasolonjatovo, B. Pitard, T. Haudebourg, V. Bennevault, et P. Guégan, « Synthesis of tetraarm star block copolymer based on polytetrahydrofuran and poly(2-methyl-2-oxazoline) for gene delivery applications », European Polymer Journal, vol. 88, p. 689-700.
    Résumé : New star shaped block copolymers were synthesized according to a core first strategy, with a hydrophobic polytetrahydrofuran (PTHF) central block and a poly(2-methyl-2-oxazoline) (PMeOx) external block. First, the cationic polymerization of THF was initiated from a tetrafunctional triflate ester synthesized in situ. The chain ends were functionalized by quenching the polymerization with an excess of MeOx, that allowed for the MeOx polymerization under microwave in a subsequent step. Demonstration of the expected structures was carried out at each step of the polymerization. The controlled molar mass of the star copolymers was kept below 5000 g mol−1 in order to mimick the structure of the efficient poloxamines for gene transfer applications. Formulations containing various concentrations of star block copolymers were intramuscularly injected in mice. Efficient gene transfer was measured at formulations with very low concentration of copolymer compared to reference standard containing Lutrol®.
    Mots-clés : CROP, Gene therapy, POLE 4, Poly(2-methyl-2-oxazoline), POLYMERES.

  • A. Six, A. Bocheux, F. Charra, F. Mathevet, D. Kreher, et A. - J. Attias, « 2D self-assembly of phenylene–vinylene tectons at the liquid–highly oriented pyrolytic graphite interface: from chain length effects to anisotropic guest–host dynamics », Nanotechnology, vol. 28, nᵒ 2, p. 025602.
    Résumé : Here we report the synthesis and characterization of a series of new phenylene–vinylene tectons. The study by scanning tunneling microscopy of their supramolecular self-assembly at the interface between a phenyloctane solution and highly oriented pyrolyticgraphite demonstrates that variation of concentration and length of alkyl chains led to the formation of different networks, a compact one and a nanoporous one, with a fine control of the lattice parameters. The study of guest–host properties of the nanoporous network revealed a selectivity toward guest compounds according to their shape and size. Moreover, the statistical analysis of pore-to-pore guest dynamics evidences an anisotropic diffusion process.
    Mots-clés : POLE 4, POLYMERES.

  • L. Sosa-Vargas, E. Kim, et A. - J. Attias, « Beyond “decorative” 2D supramolecular self-assembly: strategies towards functional surfaces for nanotechnology », Materials Horizons.
    Résumé : 2D supramolecular self-assembly has emerged as a powerful tool in nanoscience for bottom-up fabrication of well-defined and long-range ordered two-dimensional (2D) molecular nanostructures at surfaces. Following an overview of the principles of this distinctive self-assembly process, this review focuses on recent strategies developed to go beyond surface nanopatterning and to provide functional surfaces. With an emphasis on the chemical engineering of the molecular building blocks constituting the adlayer, we show that besides supported nanoporous networks, a more promising approach lies in the upstanding 3D functional building blocks mounted on the substrate. We highlight the opportunities offered by graphene, a substrate for which non-covalent functionalization by supramolecular self-assembly represents a way to either control its electronic properties or provide a new functionality. Finally, future perspectives are addressed.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 3.2 Mo (source)

  • R. Triki, A. Bougarech, M. Tessier, S. Abid, A. Fradet, et M. Abid, « Furanic–Aliphatic Polyesteramides by Bulk Polycondensation Between Furan-Based Diamine, Aliphatic Diester and Diol », Journal of Polymers and the Environment, p. 1-7.
    Résumé : In order to prepare furanic–aliphatic polyesteramides without the side reactions taking place with furan-2-carboxylic acids or esters, a furan-based diamine, 5,5′-isopropylidenebis(2-furfurylamine), was reacted in the bulk, either with (i) ethanediol and dimethyl adipate or (ii) with the corresponding aliphatic polyester (polyethylene adipate). The polycondensation involves both amine–ester and hydroxy–ester interchanges, with elimination of excess ethanediol. High-molar-mass furanic–aliphatic polyesteramides were easily obtained. Method (ii) was more efficient than method (i), but no side reactions were observed with both methods. These polyesteramides behave as amorphous random copolymers.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 979.8 ko (source)

  • Y. Xiao, D. Zeng, L. M. Mazur, A. Castiglione, E. Lacaze, B. Heinrich, B. Donnio, D. Kreher, A. - J. Attias, J. - C. Ribierre, et F. Mathevet, « A new class of nanostructured supramolecular organic semiconductors based on intertwined multi-lamellar co-assemblies in π-conjugated liquid-crystalline side-chain polymers », Polymer Journal, vol. 49, nᵒ 1, p. 31-39.
    Résumé : The control of both the mesoscopic and nanoscale organizations within thin semiconducting films is a key issue for the improvement of the charge transport properties and the achievement of high charge-carrier mobilities. In this review, we summarized our previous work devoted to the design and

    synthesis of a new type of side-chain liquid crystal π-conjugated polymeric system associating regioregular poly(3-alkylthiophene) backbones with laterally pending π-conjugated mesogenic groups. Depending on the nature of the mesogenic side groups, this specific polymer design permits the production of lamellocolumnar or lamellolamellar mesophases, resulting in an intertwined co-assembly either of lamellae and columns or of two different types of lamellae. These optimized polymeric architectures based on two chemically different moieties constitute an interesting basis for the design of novel self-organized complex semiconducting materials. By associating with judicious side groups such as n-type entities, we demonstrated that this simple and versatile strategy can produce distinct conductive channels for both types of charge carrier and can lead to a new class of supramolecular ambipolar materials that is easily processable and potentially suitable for electronic and optoelectronic applications.
    Mots-clés : POLE 4, POLYMERES.
    Pièce jointe Full Text PDF 1.9 Mo (source)


  • A. Ali Mohamed, S. Salhi, S. Abid, R. El Gharbi, et A. Fradet, « Quasi-alternating polyesteramides from ε-caprolactone and α-amino acids », Journal of Applied Polymer Science, vol. 133, nᵒ 46, p. n/a-n/a.
    Résumé : Glycine-ɛ-caprolactone-based and α-alanine-ɛ-caprolactone-based polyesteramides with a strong tendency to form alternating sequences (degree of randomness = 1.64 and 1.31) were synthesized by melt polycondensation of intermediate hydroxy- and ethyl ester-terminated amides. These intermediates were synthesized by the reaction of equimolar amounts of ɛ-caprolactone and glycine or L-α-alanine ethyl esters in mild conditions. The structure and microstructure of these polyesteramides are discussed on the basis of an in-depth nuclear magnetic resonance study. Both polyesteramides are semi-crystalline, but the glycine-based one presents the highest melting enthalpy. This polyesteramide also exhibits higher Young's modulus and stress at break than its α- and β-alanine counterparts. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44220.
    Mots-clés : biopolymers and renewable polymers, POLE 4, Polyesteramides, polyesters, POLYMERES, α-amino acids.
  • V. Ayzac, L. Bouteiller, M. Raynal, et B. Isare, « Thermo-thickening compounds for non-polar liquid », U.S. Patent EP 16203527.

  • K. Belal, S. Poitras-Jolicoeur, J. Lyskawa, G. Pembouong, G. Cooke, P. Woisel, et F. Stoffelbach, « A triple carboxylic acid-functionalized RAFT agent platform for the elaboration of well-defined telechelic 3-arm star PDMAc », Chemical Communications, vol. 52, nᵒ 9, p. 1847-1850.
    Résumé : This communication describes the synthesis of a triple acid-functionalized RAFT agent and its use to prepare well-defined 3-arm star polymers of N,N-dimethylacrylamide (DMAc). A simple esterification reaction allowed the convenient integration of three electron-rich naphthalene recognition units on the RAFT agent platform and subsequently the elaboration of a naphthalene end-decorated telechelic 3-arm star PDMAc. This functionalized star polymer was further exploited to build a hydrogel with a complementary homoditopic host unit featuring tetracationic macrocycle cyclobis(paraquat-p-phenylene) units.
    Mots-clés : POLE 4, POLYMERES.

  • K. Belal, F. Stoffelbach, J. Lyskawa, M. Fumagalli, D. Hourdet, A. Marcellan, L. De Smet, V. R. de la Rosa, G. Cooke, R. Hoogenboom, et P. Woisel, « Recognition-mediated hydrogel swelling controlled by interaction with a negative thermoresponsive LCST polymer », Angewandte Chemie International Edition, vol. 55, nᵒ 45, p. 13974-13978.
    Résumé : Most polymeric thermoresponsive hydrogels contract upon heating beyond the lower critical solution temperature (LCST) of the polymers used. Herein, we report a supramolecular hydrogel system that shows the opposite temperature dependence. When the non-thermosesponsive hydrogel NaphtGel, containing dialkoxynaphthalene guest molecules, becomes complexed with the tetra cationic macrocyclic host CBPQT4+, swelling occurred as a result of host–guest complex formation leading to charge repulsion between the host units, as well as an osmotic contribution of chloride counter-ions embedded in the network. The immersion of NaphtGel in a solution of poly(N-isopropylacrylamide) with tetrathiafulvalene (TTF) end groups complexed with CBPQT4+ induced positive thermoresponsive behaviour. The LCST-induced dethreading of the polymer-based pseudorotaxane upon heating led to transfer of the CBPQT4+ host and a concomitant swelling of NaphtGel. Subsequent cooling led to reformation of the TTF-based host–guest complexes in solution and contraction of the hydrogel.
    Mots-clés : POLE 4, POLYMERES.

  • C. Ben Osman, R. Geagea, et F. Stoffelbach, « Synthesis of a new donor-acceptor-donor functionalized alkoxyamine and its use in a reversibly supported catalytic hybrid system for ATRP of MMA », Polymer, vol. 99, p. 654-661.
    Résumé : A new 2,6-diaminopyridine-functionalized SG1-based alkoxyamine has been synthesized and used to prepare a well-defined functional copolymer (poly(styrene-co-2-vinyl-4,4-dimethyl-5-oxazolone) – poly(S-co-VDM)) by nitroxide mediated polymerization. After post-modification of the copolymer with an atom transfer radical polymerization (ATRP) ligand (N,N-dipicolyl propylamine), the macroligand was successfully used for the homogeneous ATRP of methyl methacrylate (MMA) leading to a controlled polymerization process. The ATRP of the same monomer was also investigated with the macroligand being reversibly immobilized via hydrogen bonding onto thymine-functionalized silica nanoparticles. The ATRP of MMA involving the supported-catalyst was also effective leading to a good control over the polymerization as observed with the free macroligand and producing polymers with very low dispersity (<1.2). After separation of the supported catalyst by centrifugation, the amount of residual catalyst in the resulting polymers was determined.
    Mots-clés : ATRP, Hydrogen bonding, Macroligand, Picolyl amine, POLE 4, POLYMERES, Silica nanoparticle, supported catalyst.

  • V. Besse, N. Illy, G. David, S. Caillol, et B. Boutevin, « A Chitosan Derivative Containing Both Carboxylic Acid and Quaternary Ammonium Moieties for the Synthesis of Cyclic Carbonates », ChemSusChem, vol. 9, nᵒ 16, p. 2167-2173.
    Résumé : Chitosan, a renewable feedstock, is modified and used as a catalytic support in the presence of potassium iodide. The system is highly efficient towards the incorporation of carbon dioxide (CO2) into epoxides. It demonstrates very good thermal stability and is recyclable more than five times without loss of activity. The optimal reaction conditions were determined using allylglycidyl ether as a model and extended to a wide range of other epoxides. Cyclic carbonates were obtained with very high yield in a few hours under mild conditions (2–7 bar≈0.2–0.7 MPa, 80 °C) and no solvent.
    Mots-clés : chitosan, cyclic carbonates, epoxides, heterogeneous catalysis, POLE 4, POLYMERES, supported catalyst.

  • X. Callies, C. Fonteneau, S. Pensec, L. Bouteiller, G. Ducouret, et C. Creton, « Adhesion and non-linear rheology of adhesives with supramolecular crosslinking points », Soft Matter, vol. 12, nᵒ 34, p. 7174-7185.
    Résumé : Soft supramolecular materials are promising for the design of innovative and highly tunable adhesives. These materials are composed of polymer chains functionalized by strongly interacting moieties, sometimes called “stickers”. In order to systematically investigate the effect of the presence of associative groups on the debonding properties of a supramolecular adhesive, a series of supramolecular model systems has been characterized by probe-tack tests. These model materials, composed of linear and low dispersity poly(butylacrylate) chains functionalized in the middle by a single tri-urea sticker, are able to self-associate by six hydrogen bonds and range in molecular weight (Mn) between 5 and 85 kg mol−1. The linear rheology and the nanostructure of the same materials (called “PnBA3U”) were the object of a previous study. At room temperature, the association of polymers via hydrogen bonds induces the formation of rod-like aggregates structured into bundles for Mn < 40 kg mol−1 and the behavior of a soft elastic material was observed (G′ ≪ G′′ and G′ ∼ ω0). For higher Mn materials, the filaments were randomly oriented and the polymers displayed a crossover towards viscous behavior although terminal relaxation was not reached in the experimental frequency window. All these materials show, however, similar adhesive properties characterized by a cohesive mode of failure and low debonding energies (Wadh < 40 J m−2 for a debonding speed of 100 μm s−1). The debonding mechanisms observed during the adhesion tests have been investigated in detail with an Image tools analysis developed by our group. The measure of the projected area covered by cavities growing in the adhesive layer during debonding can be used to estimate the true stress in the walls of the cavities and thus to characterize the in situ large strain deformation of the thin layer during the adhesion test itself. This analysis revealed in particular that the PnBA3U materials with Mn < 40 kg mol−1 soften very markedly at large deformation like yield stress fluids, explaining the low adhesion energies measured for these viscoelastic gels.
    Mots-clés : POLE 4, POLYMERES.

  • X. Callies, O. Herscher, C. Fonteneau, A. Robert, S. Pensec, L. Bouteiller, G. Ducouret, et C. Creton, « Combined Effect of Chain Extension and Supramolecular Interactions on Rheological and Adhesive Properties of Acrylic Pressure-Sensitive Adhesives », ACS Applied Materials & Interfaces, vol. 8, nᵒ 48, p. 33307-33315.
    Résumé : A new approach for the elaboration of low molecular weight pressure-sensitive adhesives based on supramolecular chemistry is explored. The synthesis of model systems coupled with probe-tack tests and rheological experiments highlights the influence of the transient network formed by supramolecular bonds on the adhesion energy. The first step of our approach consists of synthesizing poly(butyl acrylate-co-glycidyl methacrylate) copolymers from a difunctional initiator able to self-associate by four hydrogen bonds between urea groups. Linear copolymers with a low dispersity (Mn = 10 kg/mol, Ip < 1.4) have been synthesized via atom transfer radical polymerization. Films of the copolymers were then partially cross-linked through reaction of the epoxy functions with a diamine. The systematic variation of the average ratio of glycidyl methacrylate and diamine per copolymer shed light on the respective role played by the supramolecular interactions (between bis-urea groups and with the side chains) and by the chain extension and branching induced by the diamine/epoxy reaction. In this strategy, the adhesive performance can be optimized by modifying the strength of “stickers” (via the structure of the supramolecular initiator, for instance) and the polymer network (e.g., via the length and level of branching of the copolymer chains) in order to approach commercial PSA-like properties (high debonding energy and clean removal).
    Mots-clés : POLE 4, POLYMERES.
  • V. Calvez, A. G. Marcellin, L. Bouteiller, M. Menand, P. Evenou, A. Gothland, D. Colesnic, J. Rossignol, et M. Sollogoub, « Capped cyclodextrin-hydrophobic moiety conjugate, cyclodextrin supramolecular polymer, and cyclodextrin-siRNA complex and method of synthesis thereof », U.S. Patent PCT/ EP2016/070892.
    Mots-clés : GOBS, POLE 3, POLE 4, POLYMERES.

  • S. Catrouillet, L. Bouteiller, O. Boyron, C. Lorthioir, E. Nicol, S. Pensec, et O. Colombani, « Patchy Supramolecular Bottle-Brushes Formed by Solution Self-Assembly of Bis(urea)s and Tris(urea)s Decorated by Two Incompatible Polymer Arms », Langmuir, vol. 32, nᵒ 35, p. 8900-8908.
    Résumé : In an attempt to design urea-based Janus nanocylinders through a supramolecular approach, nonsymmetrical bis(urea)s and tris(urea)s decorated by two incompatible polymer arms, namely, poly(styrene) (PS) and poly(isobutylene) (PIB), were synthesized using rather straightforward organic and polymer chemistry techniques. Light scattering experiments revealed that these molecules self-assembled in cyclohexane by cooperative hydrogen bonds. The extent of self-assembly was limited for the bis(urea)s. On the contrary, reasonably anisotropic 1D structures (small nanocylinders) could be obtained with the tris(urea)s (Nagg ∼ 50) which developed six cooperative hydrogen bonds per molecule. 1H transverse relaxation measurements and NOESY NMR experiments in cyclohexane revealed that perfect Janus nanocylinders with one face consisting of only PS and the other of PIB were not obtained. Nevertheless, phase segregation between the PS and PIB chains occurred to a large extent, resulting in patchy cylinders containing well separated domains of PIB and PS chains. Reasons for this behavior were proposed, paving the way to improve the proposed strategy toward true urea-based supramolecular Janus nanocylinders.
    Mots-clés : POLE 4, POLYMERES.

  • X. Caumes, A. Baldi, G. Gontard, P. Brocorens, R. Lazzaroni, N. Vanthuyne, C. Troufflard, M. Raynal, et L. Bouteiller, « Tuning the structure of 1,3,5-benzene tricarboxamide self-assemblies through stereochemistry », Chemical Communications, vol. 52, nᵒ 91, p. 13369-13372.
    Résumé : A heterochiral 1,3,5-benzene tricarboxamide (BTA) monomer, derived from valine dodecyl ester, forms long rods in cyclohexane whilst its homochiral analogue assembles into dimers only at the same concentration. This highly original assembly behaviour is related to the destabilization of the dimeric structure containing the two heterochiral monomers as corroborated by a combined experimental and computational study.
    Mots-clés : POLE 4, POLYMERES.

  • M. C. Chong, G. Reecht, H. Bulou, A. Boeglin, F. Scheurer, F. Mathevet, et G. Schull, « Narrow-Line Single-Molecule Transducer between Electronic Circuits and Surface Plasmons », Physical Review Letters, vol. 116, nᵒ 3, p. 036802.
    Résumé : A molecular wire containing an emitting molecular center is controllably suspended between the plasmonic electrodes of a cryogenic scanning tunneling microscope. Passing current through this circuit generates an ultranarrow-line emission at an energy of ≈1.5 eV which is assigned to the fluorescence of the molecular center. Control over the linewidth is obtained by progressively detaching the emitting unit from the surface. The recorded spectra also reveal several vibronic peaks of low intensities that can be viewed as a fingerprint of the emitter. Surface plasmons localized at the tip-sample interface are shown to play a major role in both excitation and emission of the molecular excitons.
    Mots-clés : POLE 4, POLYMERES.

  • M. C. Chong, L. Sosa-Vargas, H. Bulou, A. Boeglin, F. Scheurer, F. Mathevet, et G. Schull, « Ordinary and Hot Electroluminescence from Single-Molecule Devices: Controlling the Emission Color by Chemical Engineering », Nano Letters, vol. 16, nᵒ 10, p. 6480-6484.
    Résumé : Single-molecule junctions specifically designed for their optical properties are operated as light-emitting devices using a cryogenic scanning tunneling microscope. They are composed of an emitting unit—a molecular chromophore—suspended between a Au(111) surface and the tip of the microscope by organic linkers. Tunneling electrons flowing through these junctions generate a narrow-line emission of light whose color is controlled by carefully selecting the chemical structure of the emitting unit. Besides the main emission line, red and blue-shifted vibronic features of low intensity are also detected. While the red-shifted features provide a spectroscopic fingerprint of the emitting unit, the blue-shifted ones are interpreted in terms of hot luminescence from vibrationally excited states of the molecule.
    Mots-clés : POLE 4, POLYMERES.
  • A. Debuigne, M. Dréan, P. Guégan, C. Jérôme, P. Midoux, et J. Rieger, « Improvements in or Relating to Organic Material », U.S. Patent EP16165764.

  • A. Desmarchelier, B. G. Alvarenga, X. Caumes, L. Dubreucq, C. Troufflard, M. Tessier, N. Vanthuyne, J. Idé, T. Maistriaux, D. Beljonne, P. Brocorens, R. Lazzaroni, M. Raynal, et L. Bouteiller, « Tuning the nature and stability of self-assemblies formed by ester benzene 1,3,5-tricarboxamides: the crucial role played by the substituents », Soft Matter, vol. 12, nᵒ 37, p. 7824-7838.
    Résumé : As the benzene 1,3,5-tricarboxamide (BTA) moiety is commonly used as the central assembling unit for the construction of functionalized supramolecular architectures, strategies to tailor the nature and stability of BTA assemblies are needed. The assembly properties of a library of structurally simple BTAs derived from amino dodecyl esters (ester BTAs, 13 members) have been studied, either in the bulk or in cyclohexane solutions, by means of a series of analytical methods (NMR, DSC, POM, FT-IR, UV-Vis, CD, ITC, high-sensitivity DSC, SANS). Two types of hydrogen-bonded species have been identified and characterized: the expected amide-bonded helical rods (or stacks) that are structurally similar to those formed by BTAs with simple alkyl side chains (alkyl BTAs), and ester-bonded dimers in which the BTAs are connected by means of hydrogen bonds linking the amide N–H and the ester CO. MM/MD calculations coupled with simulations of CD spectra allow for the precise determination of the molecular arrangement and of the hydrogen bond pattern of these dimers. Our study points out the crucial influence of the substituent attached on the amino-ester α-carbon on the relative stability of the rod-like versus dimeric assemblies. By varying this substituent, one can precisely tune the nature of the dominant hydrogen-bonded species (stacks or dimers) in the neat compounds and in cyclohexane over a wide range of temperatures and concentrations. In the neat BTAs, stacks are stable up

    to 213 °C and dimers above 180 °C whilst in cyclohexane stacks form at c* &gt; 3 × 10−5 M at 20 °C and dimers are stable up to 80 °C at 7 × 10−6 M. Ester BTAs that assemble into stacks form a liquid-crystalline phase and yield gels or viscous solutions in cyclohexane, demonstrating the importance of controlling the structure of these assemblies. Our systematic study of these structurally similar ester BTAs also allows for a better understanding of how a single atom or moiety can impact the nature and stability of BTA aggregates, which is of importance for the future development of functionalized BTA supramolecular polymers.
    Mots-clés : POLE 4, POLYMERES.

  • A. Desmarchelier, X. Caumes, M. Raynal, A. Vidal-Ferran, P. W. N. M. van Leeuwen, et L. Bouteiller, « Correlation between the Selectivity and the Structure of an Asymmetric Catalyst Built on a Chirally Amplified Supramolecular Helical Scaffold », Journal of the American Chemical Society, vol. 138, nᵒ 14, p. 4908-4916.
    Résumé : For the first time, supramolecular helical rods composed of an achiral metal complex and a complementary enantiopure monomer provided a good level of enantioinduction in asymmetric catalysis. Mixtures containing an achiral ligand monomer (BTAPPh2, 2 mol %) and an enantiopure ligand-free comonomer (ester BTA, 2.5 mol %), both possessing a complementary benzene-1,3,5-tricarboxamide (BTA) central unit, were investigated in combination with [Rh(cod)2]BArF (1 mol %) in the asymmetric hydrogenation of dimethyl itaconate. Notably, efficient chirality transfer occurs within the hydrogen-bonded coassemblies formed by BTA Ile and the intrinsically achiral catalytic rhodium catalyst, providing the hydrogenation product with up to 85% ee. The effect of the relative content of BTA Ile as compared to the ligand was investigated. The amount of chiral comonomer can be decreased down to one-fourth of that of the ligand without deteriorating the enantioselectivity of the reaction, while the enantioselectivity decreases for mixtures containing high amounts of BTA Ile. The nonlinear relationship between the amount of chiral comonomer and the enantioselectivity indicates that chirality amplification effects are at work in this catalytic system. Also, right-handed helical rods are formed upon co-assembly of the achiral rhodium complex of BTAPPh2 and the enantiopure comonomer BTA Ile as confirmed by various spectroscopic and scattering techniques. Remarkably, the major enantiomer and the selectivity of the catalytic reaction are related to the handedness and the net helicity of the coassemblies, respectively. Further development of this class of catalysts built on chirally amplified helical scaffolds should contribute to the design of asymmetric catalysts operating with low amounts of chiral entities.
    Mots-clés : POLE 4, POLYMERES.

  • M. Dréan, P. Guégan, C. Detrembleur, C. Jérôme, J. Rieger, et A. Debuigne, « Controlled Synthesis of Poly(vinylamine)-Based Copolymers by Organometallic-Mediated Radical Polymerization », Macromolecules, vol. 49, nᵒ 13, p. 4817-4827.
    Résumé : Living/controlled polymerization methods have enabled the synthesis of numerous (co)polymers with defined compositions and architectures. However, the precision design of poly(vinylamine)-based copolymers remains challenging despite their extensive use in various fields of applications and the clear benefits to finely tune their properties. Here, we report on a two-step strategy for the synthesis of tailor-made poly(vinylamine) derivatives through the organometallic-mediated radical (co)polymerization (OMRP) of N-vinylacetamide and/or N-methylvinylacetamide followed by acid hydrolysis of the acetamide groups. A series of well-defined homopolymers as well as statistical and block copolymers with pendant primary and/or secondary amines having controlled molar masses, compositions, and low dispersities were produced accordingly. The reactivity ratios of the comonomers as well as the composition drift along the chain were determined in order to have a precise idea of the polymer structures. These advances represent a significant step toward an efficient platform for synthesis of this important class of amino group-containing (co)polymers.
    Mots-clés : POLE 4, POLYMERES.

  • M. Dréan, P. Guégan, C. Jérôme, J. Rieger, et A. Debuigne, « Far beyond primary poly(vinylamine)s through free radical copolymerization and amide hydrolysis », Polymer Chemistry, vol. 7, nᵒ 1, p. 69-78.
    Résumé : Due to their affinity for many supports, their pH responsiveness, metal binding capacity and polyelectrolyte complexation, poly(vinylamine) derivatives have attracted attention for many applications including coatings, water purification, or gas membrane separation. Nevertheless, most of them possess only pendant primary amines despite the possible benefits of incorporating different amino groups along the chain. In this work, a straightforward and scalable synthesis route towards polymers bearing primary and secondary amines, as well as imidazole groups, is reported. The general strategy relies on the radical copolymerization of different vinylamides and vinyl imidazoles followed by the hydrolysis of the resulting poly(vinylamide) derivatives. Binary and ternary free radical copolymerizations of N-vinylacetamide (NVA), N-methyl vinylacetamide (NMVA) and 1-vinylimidazole (VIm) were investigated and the reactivity ratios for each copolymerization system were determined. Thanks to these values a series of statistical copolymers with predictable composition and low deviation over the chain distribution could then be synthesized. Finally, the acidic hydrolysis of the acetamide functions towards the corresponding amine was performed and optimized. Copolymers containing various pendant amino groups and with low dispersity in the chain composition could be obtained, which opens new perspectives for the above mentioned applications.
    Mots-clés : POLE 4, POLYMERES.

  • L. Duarte, S. Nag, M. Castro, E. Zaborova, M. Ménand, M. Sollogoub, V. Bennevault, J. - F. Feller, et P. Guégan, « Chemical Sensors Based on New Polyamides Biobased on (Z) Octadec-9-Enedioic Acid and β-Cyclodextrin », Macromolecular Chemistry and Physics, vol. 217, nᵒ 14, p. 1620-1628.

  • J. Dubarle-Offner, J. Moussa, H. Amouri, B. Jouvelet, L. Bouteiller, et M. Raynal, « Induced Circular Dichroism in Phosphine Gold(I) Aryl Acetylide Urea Complexes through Hydrogen-Bonded Chiral Co-Assemblies », Chemistry – A European Journal, vol. 22, nᵒ 12, p. 3985-3990.
    Résumé : Phosphine gold(I) aryl acetylide complexes equipped with a central bis(urea) moiety form 1D hydrogen-bonded polymeric assemblies in solution that do not display any optical activity. Chiral co-assemblies are formed by simple addition of an enantiopure (metal-free) complementary monomer. Although exhibiting an intrinsically achiral linear geometry, the gold(I) aryl acetylide fragment is located in the chiral environment displayed by the hydrogen-bonded co-assemblies, as demonstrated by induced circular dichroism (ICD).
    Mots-clés : ARC, gold complexes, induced circular dichroism, POLE 1, POLE 4, POLYMERES, sergeants and soldiers, supramolecular chirality, supramolecular polymers.

  • A. Giustiniani, P. Guégan, M. Marchand, C. Poulard, et W. Drenckhan, « Generation of Silicone Poly-HIPEs with Controlled Pore Sizes via Reactive Emulsion Stabilization », Macromolecular Rapid Communications, vol. 37, nᵒ 18, p. 1527-1532.

  • L. Goujard, P. - J. Roumanet, B. Barea, Y. Raoul, F. Ziarelli, J. L. Petit, N. Jarroux, E. Ferré, et P. Guégan, « Evaluation of the Effect of Chemical or Enzymatic Synthesis Methods on Biodegradability of Polyesters », Journal of Polymers and the Environment, vol. 24, nᵒ 1, p. 64-71.
    Résumé : This work compares the biodegradability of polyesters produced by an esterification reaction between glycerol and oleic di-acid (D 18:1) issued from green chemical pathways, via either classical thermo-chemical methods, or an enzymatic method using the immobilized lipase of Candida antartica B (Novozym 435). An elastomeric polymer synthesized by enzymatic catalysis is more biodegradable than an elastomeric thermo-chemical polyester synthesized by a standard chemical procedure. This difference lies in percentage of the dendritic motifs, in values of the degree of substitution, and certainly in cross-links inducing an hyper-branched structure less accessible to the lipolytic enzymes in a waste treatment plant. However, when the elastomeric polymer synthesized by enzymatic catalysis is processed at high temperature as required for certain industrial applications, it presents an identical rate of biodegradation than the chemical polyester. The advantages of the thermo-chemical methods are greater speed and lower cost. Enzymatic synthesis appears be suited to producing polyesters, devoid of metallic catalysts, which must be used without processing at high temperature to keep a high biodegradability.
    Mots-clés : POLE 4, POLYMERES.

  • C. Grazon, J. Rieger, P. Beaunier, R. Méallet-Renault, et G. Clavier, « Fluorescent core–shell nanoparticles and nanocapsules using comb-like macromolecular RAFT agents: synthesis and functionalization thereof », Polymer Chemistry, vol. 7, nᵒ 25, p. 4272-4283.
    Résumé : Fluorescent nanoparticles and nanocapsules (FNPs) were synthesized via a one-pot RAFT miniemulsion process copolymerizing BODIPY-methacrylate and styrene in water. Ultra-bright sub-100 nm core–shell nanoparticles could be obtained with BODIPY covalently linked in the core, and possessing various shells. The nature and architecture of the particle shells could be tuned by using different macromolecular RAFT (macro-RAFT) agents in the miniemulsion polymerization process. The macro-RAFT agents were composed of poly(ethylene oxide) acrylate (PEOA) and/or acrylic acid (AA), owing to their biocompatibility and functionality respectively, in different proportions. Interestingly, with comb-like macro-RAFT agents comprising a high number of PEOA, nanocapsules were formed, while with linear macro-RAFT agents or with those exhibiting a high number of AA, full core–shell nanoparticles were obtained. For all the structures the control over the polymerization, the size, morphology, and zeta-potential as well as the photophysical properties were measured and compared with FNPs exhibiting a linear PEO-b-PAA block copolymer shell structure (C. Grazon, J. Rieger, R. Méallet-Renault, G. Clavier and B. Charleux, Macromol. Rapid Commun., 2011, 32, 699). Regardless of the shell structures, the brightness of the formed nanoparticles was estimated to be 100–1000 times higher than that of quantum dots. Ultimately, the shell of the different FNPs was functionalized with a second fluorophore via the AA's carboxyl groups. Thus, water-soluble ultra-bright FNPs with two fluorophores in distinct environments (water and in polystyrene) were obtained. They should have great potential for bioimaging applications.
    Mots-clés : POLE 4, POLYMERES.

  • C. T. Howells, K. Marbou, H. Kim, K. J. Lee, B. Heinrich, S. J. Kim, A. Nakao, T. Aoyama, S. Furukawa, J. - H. Kim, E. Kim, F. Mathevet, S. Mery, I. D. W. Samuel, A. A. Ghaferi, M. S. Dahlem, M. Uchiyama, S. Y. Kim, J. W. Wu, J. - C. Ribierre, C. Adachi, D. - W. Kim, et P. André, « Enhanced organic solar cells efficiency through electronic and electro-optic effects resulting from charge transfers in polymer hole transport blends », Journal of Materials Chemistry, vol. 4, nᵒ 11, p. 4252-4263.
    Résumé : We demonstrate that blending fluorinated molecules in PEDOT:PSS hole transport layers (HTL) induces charge transfers which impact on both charge extraction and photogeneration within organic photovoltaic (OPV) devices. OPVs fabricated with modified HTL and two photoactive polymer blends led systematically to power conversion efficiencies (PCE) increases, with PTB7:PC70BM blend exhibiting PCE of ∼8.3%, i.e. ∼15% increase compared to pristine HTL devices. A reduced device-to-device characteristics variations was also noticed when fluorinated additives were used to modify the PEDOT:PSS. Shading lights onto the effect of HTL fluorination, we show that the morphology of the polymer:PCBM blends remains surprisingly unaffected by the fluorinated HTL surface energy but that, instead, the OPVs are impacted not only by the HTL electronic properties (work function, dipole layer, open circuit voltage, charge transfer dynamic) but also by alteration of the complex refractive indices (photogeneration, short circuit current density, external quantum efficiencies, electro-optic modelling). Both mechanisms find their origin in fluorination induced charge transfers. This work points towards fluorination as a promising strategy toward combining both external quantum efficiency modulation and power conversion efficiency enhancement in OPVs. Charge transfers could also be used more broadly to tune the optical constants and electric field distribution, as well as to reduce interfacial charge recombinations within OPVs.
    Mots-clés : POLE 4, POLYMERES.

  • B. Isare, S. Pensec, M. Raynal, et L. Bouteiller, « Bisurea-based supramolecular polymers: From structure to properties. », Comptes Rendus Chimie, vol. 19, nᵒ 1–2, p. 148-156.
    Résumé : This review focuses on the synthesis, self-assembled structure and properties of bisurea-based supramolecular polymers. The straightforward synthetic accessibility of the bisurea synthon has allowed the systematic description of the relationship between the molecular structure and supramolecular assembly. Remarkably, these systems self-assemble at equilibrium into two competing supramolecular structures. Therefore, the assembly of low molar mass bisureas can lead to stimuli responsive viscoelastic gels as well as to systems which are able to report on weak intermolecular interactions. When deposited on surfaces, these hydrogen-bonded chains of molecules form well-organized monolayers in spite of defects from the substrate. Moreover, polymers with improved rheological or adhesive properties can be designed by grafting bisurea stickers.
    Mots-clés : Gels, monolayers, nanostructures, nanotubes, POLE 4, POLYMERES, polymers, Self-assembly, Supramolecular chemistry, Thermodynamics.

  • J. Lazko, T. Sénéchal, A. Bouchut, Y. Paint, L. Dangreau, A. Fradet, M. Tessier, J. M. Raquez, et P. Dubois, « Acid-free extraction of cellulose type I nanocrystals using Brønsted acid-type ionic liquids », Nanocomposites, vol. 2, nᵒ 2, p. 65-75.
    Résumé : Extraction of cellulose type I nanocrystals from cotton fibers was straightforwardly carried out using exclusively Brønsted acid-type ionic liquids (ILs) via a two-step swelling/hydrolysis route, the switch between these two stages being induced by water addition. Since the whole process was achieved in a single reaction medium predominantly based on 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and 1-(4-sulfobutyl)-3-methylimidazolium hydrogen sulfate ([SBMIM]HSO4), the process parameters were investigated in order to ensure a perfect compatibility and sequencing towards the two-step route proposed here. The impacts on nanoparticle morphology, crystallinity evolution, and cellulose type I to type II denaturation were observed under field-emission gun scanning electron microscopy and corroborated by X-ray diffraction characterizations. ILs recovery and reuse were also demonstrated, opening up new prospects of conception of multi-cycle, environmentally and economically sustainable processes.
    Mots-clés : Cellulose nanocrystals, hydrolysis, Ionic liquids, POLE 4, POLYMERES, Recycling, Swelling.

  • S. Le Liepvre, P. Du, D. Kreher, F. Mathevet, A. - J. Attias, C. Fiorini-Debuisschert, L. Douillard, et F. Charra, « Fluorescent Self-Assembled Molecular Monolayer on Graphene », ACS Photonics, vol. 3, nᵒ 12, p. 2291-2296.
    Résumé : We report the first fluorescent molecular self-assembly on graphene. The quenching of the fluorescence of the adsorbed dye by the adjacent graphene is hindered at the molecular scale based on a spacer approach, through a specifically designed dual-functionalized self-assembling building block. This 3D tecton presents two faces, one forming a noncovalent graphene-binding pedestal and the other carrying a dye group linked by a spacer to the pedestal. The spontaneous ordering of the adsorbed layer is investigated by scanning tunneling microscopy, whereas the resulting optical properties of the whole graphene–dye hybrid system are characterized by absorption and fluorescence spectroscopies.
    Mots-clés : POLE 4, POLYMERES.

  • K. J. Lee, J. H. Woo, E. Kim, Y. Xiao, X. Su, L. M. Mazur, A. - J. Attias, F. Fages, O. Cregut, A. Barsella, F. Mathevet, L. Mager, J. W. Wu, A. D'Aléo, et J. - C. Ribierre, « Electronic energy and electron transfer processes in photoexcited donor–acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units », Physical Chemistry Chemical Physics, vol. 18, nᵒ 11, p. 7875-7887.
    Résumé : We investigate the photophysical properties of organic donor–acceptor dyad and triad molecular systems based on triphenylene and perylene diimide units linked by a non-conjugated flexible bridge in solution using complementary optical spectroscopy techniques. When these molecules are diluted in dichloromethane solution, energy transfer from the triphenylene to the perylene diimide excited moieties is evidenced by time-resolved fluorescence measurements resulting in a quenching of the emission from the triphenylene moieties. Simultaneously, another quenching process that affects the emission from both donor and acceptor units is observed. Solution ultrafast transient absorption measurements provide evidence of photo-induced charge transfer from either the donor or the acceptor depending upon the excitation. Overall, the analysis of the detailed time-resolved spectroscopic measurements carried out in the dyad and triad systems as well as in the triphenylene and perylene diimide units alone provides useful information both to better understand the relations between energy and charge transfer processes with molecular structures, and for the design of future functional dyad and triad architectures based on donor and acceptor moieties for organic optoelectronic applications.
    Mots-clés : POLE 4, POLYMERES.

  • K. J. Lee, J. H. Woo, Y. Xiao, E. Kim, L. M. Mazur, D. Kreher, A. - J. Attias, K. Matczyszyn, M. Samoc, B. Heinrich, S. Méry, F. Fages, L. Mager, A. D'Aléo, J. W. Wu, F. Mathevet, P. André, et J. - C. Ribierre, « Structure–charge transfer property relationship in self-assembled discotic liquid-crystalline donor–acceptor dyad and triad thin films », RCS Advances, vol. 6, nᵒ 63, p. 57811-57819.
    Résumé : The photophysical properties of donor–acceptor (D–A) and donor–acceptor–donor (D–A–D) liquid crystalline dyads and triads based on two different discotic mesogens are examined in thin films by steady-state optical spectroscopy and subpicosecond transient absorption measurements. In these systems, triphenylene and perylene bisimide units are covalently linked by flexible decyloxy chain(s) and act as an electron donor (D) and acceptor (A), respectively. These discotic liquid-crystalline systems form well-separated D and A π-stacked columnar structures in thin films. The absorption spectra of the films indicate an aggregation of the perylene bisimide and triphenylene moieties along the columns. Steady-state photoluminescence measurements show a strong fluorescence quenching that is mainly attributed to a photo-induced charge transfer process taking place between the triphenylene and perylene bisimide units. Subpicosecond transient absorption measurements show that the photoinduced charge transfer (CT) states in the dyad and triad films are formed within 0.3 ps and recombine on a 150–360 ps time scale. In addition, a correlation between the dynamics of the charge recombination process and the spacing distances between D and A units can be established in the dyad and triad films. This study provides important information on the relationship between molecular packing and the charge transfer properties in such self-organized D and A columnar nanostructures.
    Mots-clés : POLE 4, POLYMERES.

  • N. Mansour, K. Hriz, N. Jaballah, D. Kreher, et M. Majdoub, « Synthesis, characterization, optical and electrical properties of bis(phenylvinyl)anthracene-based polymers », Optical Materials, vol. 58, p. 296-305.
    Résumé : A series of bis(phenylvinyl)anthracene-based polymers containing different lengths of polar ethylene glycol groups in the main chain (P1–3) were efficiently synthesized by Wittig polycondensation. These polymers are fully soluble in volatile solvents, which helped a lot to obtain high quality films. Moreover, these semi-conducting materials exhibited semi-crystalline morphology with relatively high glass transition temperature. In this article, the UV–visible absorption and fluorescence properties of P1–3 were studied consequently both in solution and as thin solid film: tan absorption-onset at 433 nm was observed and all these bis(phenylvinyl)anthracene-based polymers (P1–3) show a blue emission in solution, fluorescence quantum efficiencies being respectively 52% for P1, 75% for P2 and 67% for P3. In addition, the HOMO/LUMO energy levels were evaluated by cyclic voltammetry measurements and indicate a p-type semi-conducting materials. Finally, the electrical properties of P1–3 were investigated by recording current-tension characteristics and these experimental results were modeled by the current space-charge-limited (SCLC) mechanism.
    Mots-clés : Anthracene, Optical properties, Organic thin layer, POLE 4, polymer synthesis, POLYMERES, Semi-conducting polymer, Space-charge limited current (SCLC).

  • T. Matsushima, F. Mathevet, B. Heinrich, S. Terakawa, T. Fujihara, C. Qin, A. S. D. Sandanayaka, J. - C. Ribierre, et C. Adachi, « N-channel field-effect transistors with an organic-inorganic layered perovskite semiconductor », Applied Physics Letters, vol. 109, nᵒ 25, p. 253301.

  • B. Rasolonjatovo, B. Pitard, T. Haudebourg, V. Bennevault, et P. Guégan, « Synthesis of tetraarm star block copolymer based on polytetrahydrofuran and poly(2-methyl-2-oxazoline) for gene delivery applications », European Polymer Journal.
    Résumé : New star shaped block copolymers were synthesized according to a core first strategy, with a hydrophobic polytetrahydrofuran (PTHF) central block and a poly(2-methyl-2-oxazoline) (PMeOx) external block. First, the cationic polymerization of THF was initiated from a tetrafunctional triflate ester synthesized in situ. The chain ends were functionalized by quenching the polymerization with an excess of MeOx, that allowed for the MeOx polymerization under microwave in a subsequent step. Demonstration of the expected structures was carried out at each step of the polymerization. The controlled molar mass of the star copolymers was kept below 5000 g mol−1 in order to mimick the structure of the efficient poloxamines for gene transfer applications. Formulations containing various concentrations of star block copolymers were intramuscularly injected in mice. Efficient gene transfer was measured at formulations with very low concentration of copolymer compared to reference standard containing Lutrol®.
    Mots-clés : CROP, Gene therapy, POLE 4, Poly(2-methyl-2-oxazoline), POLYMERES.

  • E. Ressouche, S. Pensec, B. Isare, G. Ducouret, et L. Bouteiller, « Rational Design of Urea-Based Two-Component Organogelators », ACS Macro Letters, vol. 5, nᵒ 2, p. 244-247.
    Résumé : Low molecular weight gelators are versatile and responsive gel-forming systems. However, it is still a challenge to develop a new organogelator for a precise application, i.e., to gel a predetermined liquid. We propose a simple concept of a two-component gelling system that can be rationally adapted to gel liquids ranging in polarity from silicone oil to acetonitrile.
    Mots-clés : POLE 4, POLYMERES.

  • E. Ressouche, S. Pensec, B. Isare, J. Jestin, et L. Bouteiller, « Two-Component Self-Assemblies: Investigation of a Synergy between Bisurea Stickers », Langmuir, vol. 32, nᵒ 44, p. 11664-11671.
    Résumé : It is of interest to develop two-component systems for added flexibility in the design of supramolecular polymers, nanofibers, or organogels. Bisureas are known to self-assemble by hydrogen bonding into long supramolecular objects. We show here that mixing aromatic bisureas with slightly different structures can yield surprisingly large synergistic effects. A strong increase in viscosity is observed when a bisurea with the sterically demanding 2,4,6-trimethylbenzene spacer is combined with a bisurea bearing no methyl group in position 2 of the aromatic spacer (i.e., 4-methylbenzene or 4,6-dimethylbenzene). This effect is the consequence of a change in the supramolecular assembly triggered by the composition of the mixture. The mixture of complementary bisureas forms rodlike objects that are more stable by about 1 kJ/mol and that are thicker than the rodlike objects formed by both parent systems.
    Mots-clés : POLE 4, POLYMERES.

  • Y. Si, C. Grazon, G. Clavier, J. Rieger, J. F. Audibert, B. Sclavi, et R. Méallet-Renault, « Rapid and accurate detection of Escherichia coli growth by fluorescent pH-sensitive organic nanoparticles for high-throughput screening applications. », Biosensors & bioelectronics, vol. 75, p. 320-327.
    Résumé : Abstract: Rapid detection of bacterial growth is an important issue in the food industry and for medical research. Here we present a novel kind of...
    Mots-clés : POLE 4, POLYMERES.

  • E. Velasquez, J. Rieger, F. Stoffelbach, F. D'Agosto, M. Lansalot, P. - E. Dufils, et J. Vinas, « Surfactant-free poly(vinylidene chloride) latexes via one-pot RAFT-mediated aqueous polymerization », Polymer, vol. 106, p. 275-284.

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