International audience1,2,3-Triazolium-based poly(ionic liquid)s containing a triethylene glycol spacer were synthesized from the polyaddition of an alpha-azide-omega-alkyne monomer by copper-catalyzed azide-allcyne cycloaddition (CuAAC) followed by quaternization reactions with alkyl halides and subsequent anion exchanges with different fluorinated salts. A detailed structure-property relationship for solubility, thermal stability, and ionic conductivity was investigated by means of H-1 NMR spectroscopy, differential scanning calorimetry (DSC), thermogravinietric analysis (TGA), and broadband dielectric spectroscopy (BDS). One of these poly(ionic liquid)s with a methyl substituent and bis(trifluoromethylsulfonyl)imide anion exhibits an ionic conductivity of 2 x 10(-5) S cm(-1) at 30 degrees C, which is on par with the best PILs with side-chain charge carriers reported so far and is much higher than any previously reported ionenes. The straightforward synthesis along with the broad structural design and enhanced properties of this new class of poly(ionic liquid)s offer both fundamental and applicative perspectives

A series of four 1,2,3-triazolium-based poly(ionic liquid)s (TPILs) is synthesized from the polyaddition of different tailor-made α-azide-ω-alkyne monomers by copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), followed by quaternization with methyl iodide and subsequent anion exchange with lithium bis(trifl uoromethylsulfonyl)imide. Whereas the chemical structures of the bis(trifl uoromethylsulfonyl)imide counter anion and the N -3 methyl group are common to all TPILs, the structural features of the repeating units, i.e., triethylene glycol or undecanoyl spacers with either ester or ether linkages, are varied and compared. Their impact on the physical and ion-conducting properties of the obtained TPILs is established based on 1 H NMR, DSC, thermogravimetric analysis (TGA), and broadband di electric spectroscopy (BDS) characterization techniques. Most importantly, the replacement of an ether by an ester group at the C -4 position of the 1,2,3-triazolium ring signifi cantly decreases the thermal stability and ionic conductivity of TPILs, whereas the chemical nature of the triethylene glycol or undec anoyl spacers has little infl uence on the materials properties.

International audienceVinyl levulinate is synthesized from levulinic acid by palladium-catalyzed vinyl exchange and is characterized by NMR and ESI-HRMS techniques. Homopolymerization of vinyl levulinate and random copolymerization with vinyl acetate by cobalt-mediated radical polymerization affords well-defined ketone functionalized poly(vinyl ester)s. The impact of temperature, solvent and theoretical degree of polymerization on monomer conversion and control of the polymerization is studied by H-1 NMR and size exclusion chromatography techniques. The ketoxime conjugation of O-benzylhydroxylamine with the pendant ketone functionality of poly(vinyl levulinate-co-vinyl acetate) is demonstrated

Vinyl levulinate (VL) is used as a biobased reactive diluent in styrene (St)-free unsaturated polyester resins (UPR). The reactivity ratios for the radical copolymerization of VL with diethyl fumarate (DEF) are determined by the Jaacks method (r VL 5 0.01 and r DEF 5 0.81 at 60 C in DMSO-d 6 ). The properties of UPRs having a stoichiometric ratio between unsaturated groups from the UPR and either St or VL are compared. Defect-free, slightly yellow, transparent, and rigid thermosets are obtained after a mild curing cycle. Due to unfavorable reactivity ratios about 5.5 wt % of unpolymerized VL remains inside the network and acts as plasticizer. Consequently, compared with St-based ones, VL-based UPRs exhibit lower a relaxation (T a 5 180 and 100 C, respectively), lower elastic moduli at the rubbery plateau (G 0 5 10 8 and 10 7 Pa) and lower mechanical properties as measured by three points bending tests. Strain at break (e f 5 1.8 6 0.2%) and Charpy impact strength (2.7 6 0.3 kJ m 22 ) are comparable independently of the RD chemical nature.

International audienceA straightforward and expeditious monotopic approach for the preparation of 1,2,3-triazolium-based poly(ionic liquids) (TPILs) is reported. It is based on the solvent- and catalyst-free polyaddition of an α-azide-ω-alkyne monomer in the presence of methyl iodide or N-methyl bis[(trifluoromethyl)sulfonyl]imide alkylating agents. Poly(1,2,3-triazole)s generated in bulk or by thermal azide-alkyne cycloaddition (AAC) are quaternized in-situ to afford TPILs composed of 1,3,4- and 1,3,5-trisubstituted 1,2,3-triazolium units. The physical and ion-conducting properties of the prepared samples are compared with the TPILs composed solely of 1,3,4-trisubstituted 1,2,3-triazolium units obtained through a multistep approach involving copper(I)-catalyzed AAC polyaddition, quaternization of the 1,2,3-triazole groups, and anion metathesis. TPILs obtained through the monotopic approach display thermal stabilities and ionic conductivities comparable to their pure regioisomeric analogues

Front Cover: 1,2,3‐Triazolium‐based poly(ionic liquid)s are prepared by a solvent‐ and catalyst‐free monotopic approach based on thermal polyaddition of an α‐azide‐ω‐alkyne and in‐situ quaternization of the resulting 1,4‐/1,5‐disubstituted poly(1,2,3‐triazole) s. While a significant reduction in time, number of synthetic and purification steps is achieved, the resulting ion conducting materials have properties comparable to their pure 1,3,4‐trisubstituted regioisomers. Further details can be found in the article by M. M. Obadia, B. P. Mudraboyina, I. Allaoua, A. Haddane, D. Montarnal, A. Serghei, and E. Drockenmuller* on page 794.

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