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In this communication, an atmospheric one-step plasma-based method is reported for the simultaneous synthesis and deposition of robust redox-active catechol-rich polymers. The bioinspired films are characterized by combining various analytical techniques, including IR, XPS, AFM and SIMS, and their potentials as organic cathode materials for lithium ion battery demonstrated. The influence of the coating thickness on the applicative properties of the films is also investigated.

alpha-Alkylidene cyclic carbonates (alpha CCs) recently emerged as attractive CO2-sourced synthons for the construction of complex organic molecules. Herein, we report the transformation of alpha CCs into novel families of sulfur-containing compounds by organocatalyzed chemoselective addition of thiols, following a domino process that is switched on/off depending on the desired product. The process is extremely fast and versatile in substrate scope, provides selectively linear thiocarbonates or elusive tetrasubstituted ethylene carbonates with high yields following a 100 % atom economy reaction, and valorizes CO2 as a renewable feedstock. It is also exploited to produce a large diversity of unprecedented functional polymers. It constitutes a robust platform for the design of new sulfur-containing organic synthons and important families of polymers.

We report on the synthesis of a new polymer ionic liquid (PIL) based on polyvinylimidazolium bearing a pendent nitroxide radical on each monomer unit. Firstly, the quaternization of 1-vinylimidazole by a brominated alkoxyamine, i.e. a protected tetramethylpiperidinyloxy (TEMPO) nitroxide, was achieved. Then, the bromide anion was substituted by anion exchange reaction for the bis(trifluoro-methanesulfonyl)imide (TFSI) anion. The as-obtained monomer was successfully polymerized by free radical polymerization at low temperature (40 °C) by using 2,2′-azobis(4-methoxy-2.4-dimethyl valeronitrile) as initiator. Finally, the C O bond of the alkoxyamine pendant groups was thermally cleaved releasing the redox-active TEMPO nitroxide radicals. The PIL bearing TEMPO groups was coated onto a carbon nanotubes buckypaper and tested as cathode in a lithium ion battery. Such battery remarkably exhibits a high charge/discharge rate capability, e.g. at 60C the full charge is reached in 1 min and a high cycling stability; 100% of the initial capacity 60 mA h/g is kept after 1300 cycles.

Hierarchical porous N-doped carbon (NPC) is prepared by pyrolysis of poly(methyl methacrylate) (PMMA) particles decorated by graphene oxide (GO) and polypyrrole (PPy) as precursors and used as anode for lithium-ion batteries. The composite precursors with different diameter and composition (PMMA/GO/PPy-A and B) were conveniently prepared by dispersion polymerization of methyl methacrylate in the presence of graphene oxide as stabilizer in aqueous medium, followed by addition of pyrrole and its oxidative polymerization. After pyrolysis, the resulting NPC composites with hierarchically structured macro- and mesopores exhibit high surface area (289–398 m2/g) and different N-doping levels (7.46 and 4.22 wt% of nitrogen content). The NPC with the highest N-doping level (7.46 wt%) shows high reversible capacities of 831 mAh/g at 74.4 mA/g (C/5) after 50 cycles and excellent rate performances.

In the last few years, polycarbonates have been identified as alternatives to poly(ethylene oxide) as polymer electrolytes for lithium battery applications. In this work, we show the design of CO2-sourced polycarbonates for their use in room temperature operating lithium batteries. Novel functional polycarbonates with alternating oxo-carbonate moieties and polyethylene oxide segments are synthesized by the facile room temperature (rt) organocatalyzed polyaddition of CO2-sourced bis(aalkylidene carbonate)s (bis-aCCs) with polyethylene oxide diols. The effect of the molar mass of olyethylene oxide on the ionic conductivity and thermal properties of poly(oxo-carbonate)s is investigated. The best candidate shows a low glass transition temperature of 44 C and a high ionic conductivity of 3.75 10 5 S cm 1 at rt when loaded with 30 wt% bis(trifluoromethanesulfonyl)imide salt (LiTFSI) without any solvent. An all-solid semi-interpenetrated network polymer electrolyte (SIN-SPE) is then fabricated by UV cross-linking of a mixture containing specifically designed poly(oxo-carbonate) bearing methacrylate pendants, diethylene glycol diacrylate and the previously described poly(oxocarbonate) containing LiTFSI. The resulting self-standing membrane exhibits a high oxidation stability up to 5 V (vs. Li/Li+), an ionic conductivity of 1.1 10 5 S cm 1 at rt (10 4 S cm 1 at 60 C) and promising mechanical properties. Assembled in a half cell configuration with LiFePO4 (LFP) as the cathode and lithium as the anode, the all-solid cell delivers a discharge capacity of 161 mA h g 1 at 0.1C and 60 C, which is very close to the theoretical capacity of LFP (170 mA h g 1). Also, a stable reversible cycling capacity over 400 cycles with a high coulombic efficiency of 99% is noted at 1C. Similar results are obtained at rt provided that 10 wt% tetraglyme as a plasticizer was added to the SIN-SPE. -Fonds National pour la Recherche Scientifique” (F.R.S.-FNRS) -Fonds Wetenschappelijk Onderzoek– Vlaanderen (FWO) -EOS project no. 019618F (ID EOS: 30902231). - CESAM Research Unit. - European Research Council by Starting Grant Innovative Polymers for Energy Storage (iPes) 306250 -Basque Government through ETORTEK Energigune 2013 and IT 999-16. - Spanish Ministry of Education, Culture and Sport for the predoctoral FPU fellowship received

The cobalt-mediated radical polymerization (CMRP) of new ionic liquid monomers (ILMs), vinyl imidazolium functionalized with redox-active free radical 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)VIm and its CMR copolymerization with vinyl imidazolium units functionalized with triethylene oxide (TEG)VIm produced a well-defined PILs (co)polymers. The controlled nature of (co)polymerization can be seen from the linear first-order kinetic plot, linear evolutions of the molar mass with total monomer conversion and the low polydispersity of the resulting (co)polymers. By combining the redox activity of (TEMPO)PVIm and remarkable ionic conductivity of (TEG)PVIm, outstanding rate capability performance was achieved with a remarkable capacity of 69 mAh g−1 at 60C. The obtained organic electrode can serve as sustainable electrodes in lithium ion batteries.

The performance of lithium and sodium ion batteries relies notably on the accessibility to carbon electrodes of controllable porous structure and chemical composition. This work reports a facile synthesis of well-defined porous N-doped carbons (NPCs) using a poly(ionic liquid) (PIL) as precursor, and graphene oxide (GO)-stabilized poly(methyl methacrylate) (PMMA) nanoparticles as sacrificial template. The GO-stabilized PMMA nanoparticles were first prepared and then decorated by a thin PIL coating before carbonization. The resulting NPCs reached a satisfactory specific surface area of up to 561 m2/g and a hierarchically meso- and macroporous structure while keeping a nitrogen content of 2.6 wt %. Such NPCs delivered a high reversible charge/discharge capacity of 1013 mA h/g over 200 cycles at 0.4 A/g for lithium ion batteries (LIBs), and showed a good capacity of 204 mA h/g over 100 cycles at 0.1 A/g for sodium ion batteries (SIBs)., Comment: 14 pages, 9 figures

A new strategy for the synthesis of a well-defined redox active polymer, a polyacrylate bearing TEMPO, and its grafting onto a gold substrate is described. It consists of polymerizing an acrylate bearing an alkoxyamine by RAFT, followed by aminolysis of the trithiocarbonate chain-end into a thiol that is exploited for the polymer grafting onto the gold sensor. Thermal activation of the alkoxyamine under air provides the redox polymer with a high yield. Its electroactivity is evaluated by a electrochemical quartz crystal microbalance (EQCM).

To establish a correlation between the molecular structure, physicochemical properties, thin film morphology, charge carrier mobility and photovoltaic performance of isoindigo-based electron donor type molecular semiconductors, a series of branched and linear A2–D–A1–D–A2 small molecules (A = acceptor, D = donor) are synthesized. The extended π-conjugated molecular chromophores have an electron-accepting isoindigo core, a bridging oligothiophene electron donor part and terminal octyl cyanoacrylate acceptor moieties. Their photophysical, thermal and electrochemical properties are analysed and the materials are applied in organic field-effect transistors and bulk heterojunction organic solar cells. Compared to an analogous benzothiadiazole-based small molecule, the isoindigo core deepens the HOMO energy level, enabling higher open-circuit voltages in organic solar cells. The linear isoindigo-based small molecule shows an enhanced hole mobility compared to the branched derivatives. The best power conversion efficiency of the investigated set is also obtained for the solar cell based on the linear (CA-3T-IID-3T-CA-l) donor molecule in combination with PC71BM.

Poly(ionic liquid)s (PILs) have attracted considerable attention as innovative single-ion solid polyelectrolytes (SPEs) in substitution to the more conventional electrolytes for a variety of electrochemical devices. Herein, we report the precise synthesis, characterization, and use as single-ion SPEs of a novel double PIL-based amphiphilic diblock copolymer (BCP), i.e., where all monomer units are of N-vinyl-imidazolium type, with triethylene glycol pendant groups in the first block and a statistical distribution of N-vinyl-3-ethyl- and N-vinyl-3-perfluorooctyl-imidazolium bromides in the second block. BCP synthesis is achieved directly in water by a one-pot process, by cobalt-mediated radical polymerization-induced self-assembly (CMR-PISA). A subsequent anion exchange reaction substituting bis(trifluoromethylsulfonyl)imide (Tf2N–) for bromide (Br–) counter-anions leads to PIL BCPs with two different lengths of the first block. They demonstrate ionic conductivity σDC = 1–3 × 10–7 S cm–1, as determined by ...

cited By 30; International audience; Highly regioregular poly[3-(4-octylphenylthiophene)] (POPT) was prepared to study the influence of phenyl groups as substituents on photovoltaic and thermal properties with respect to poly(3-hexylthiophene) (P3HT). The UV-visible absorption spectra of spin-coated films of POPT exhibited an extended absorption towards the near infrared. Differential scanning calorimetry showed the poor tendency of POPT to crystallise. In order to retain the extension in absorption and increase crystallinity, poly(3-hexylthiophene)-block-poly(3-tolylthiophene) (P3HT-b-P3TT) samples with varying ratios of P3HT and P3TT were prepared. Thermal fractionation by successive self-nucleation and annealing indicated that crystallites of P3HT were influenced by the P3TT block within the copolymers. Thermogravimetric analysis showed that thermal stabilities increased with increasing fractions of phenyl groups. Photovoltaic results of these materials blended with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) are presented and discussed. © 2007 Elsevier B.V. All rights reserved.

The preparation of α,α,β-trisubstituted β-lactones has opened the route to living anionic ring-opening polymerization of these monomers. Therefore, transfer reactions due to hydrogen abstraction were limited and it is now possible to strickly control sample molecular weight. Moreover, living end-groups lead to the preparation of block co-polymers with block controlled lenghts. In the same way, high-molecular-weight statistical co-polymers have been synthesized. Hydrolyzable micelles and nanoparticles will be prepared from these co-polymers after chemical modifications to adjust the hydrophilic/hydrophobic balance.

Hydrogen bonded assemblies are usually decomposed by polar organic solvents. However, we have succeeded in preparing a strongly associated supramolecular polymer which forms viscous solutions in competitive solvents such as tetrahydrofuran.

37-3 FIELD Section Title:Plastics Manufacture and Processing UMR 7610, Chimie des Polymeres, UPMC Univ Paris 06, Paris, Fr. FIELD URL: written in English; We report the straightforward photo-polymn. of polyacrylate films contg. bis-urea based self-assembled nanotubes. The obtained materials are characterized by gas adsorption measurements, 129Xe NMR spectroscopy and WAXS. The presence of the bis-ureas is shown by butane adsorption (at 273 K and ambient pressure) to be responsible for the formation of a significant microporosity. This porosity is however not detected by the classical argon adsorption procedure (at 77 K and low pressure). This effect is attributed to the contraction of the material at low temp. and pressure, and may be of general concern for other org. porous materials. One of the potential advantages of the present materials is that the porosity results from the self-assembled nanotubes and should therefore be independent of the matrix mech. properties. It should in particular be possible to adjust the flexibility of the matrix by changing the monomer compn. [on SciFinder(R)]

International audience; Various poly[3-(4-octylphenyl)thiophene]s (POPTs) were prepared either by oxidative polymerisation or by chain-growth Grignard metathesis (GRIM). In accordance with previous results, the former polymerisation yielded polydisperse POPT. The method based on the GRIM reaction made possible the preparation of medium and higher molecular weight polymers with lower polydispersities. The POPTs were found to have band-gaps of ca. 1.7 eV. The photovoltaic characteristics of POPTs-blend-[6,6]-phenyl C61 butyric acid methyl ester (PCBM) composites under AM 1.5 conditions in standard ITO/PEDOT-blend-PSS/ POPT-blend-PCBM/LiF/Al solar cells were studied. It was found that POPT prepared via GRIM could deliver greater efficiencies than its equivalent prepared by oxidative polymerisation. It is expected that access to even higher molecular weight POPTs may improve the efficiencies of such devices.

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