The Ouzo effect is a generic process to generate colloidal dispersions from a variety of solutes. Whereas phase diagrams have been quite easily established when nanoprecipitating polymers, the case ...of oils is less straightforward. Indeed, the short-term stability of generated nanodroplets in water/solvent mixtures complexifies the identification of the diagram boundaries. This article proposes two complementary methods, namely, fluorescence microscopy and dynamic light scattering, to determine with fair accuracy Ouzo limits in ternary systems oil/solvent/nonsolvent, without and with a surfactant, respectively. This accuracy in PD determination opens the way to a better understanding and control of the aggregation events during the nanoprecipitation process.
This review covers the literature concerning the modification of polysaccharides through controlled radical polymerizations (NMP, ATRP and RAFT). The different routes to well‐defined ...polysaccharide‐based macromolecules (block and graft copolymers) and graft‐functionalized polysaccharide surfaces as well as the applications of these polysaccharide‐based hybrids are extensively discussed.
Polysaccharide‐based hybrids using controlled radical polymerizations are reviewed in this article. Strategies to generate macromolecular materials with controlled chemical composition and architecture (in homogeneous medium) or to graft functionalize a range of polysaccharide surfaces (in heterogeneous medium) in a controlled manner are discussed in detail. In an effort to provide a basis for the further development of this category of materials, the most promising applications of these polysaccharide‐based hybrids are highlighted.
Herein, we report on one-pot fabrication of oil-filled nanocapsules wrapped with both RAFT-made glycopolymers and neutral polysaccharides (dextran and pullulan). We have made use of the ...nanoprecipitation technique, relying on coprecipitation of both oil and polymers in conditions thoroughly established from phase diagrams’ interpretation. Mixed mono- or multilayered nanocapsules were obtained through simultaneous or sequential nanoprecipitations, respectively. Incorporation of synthetic glycopolymer chains allows for precisely tailoring the dimensions of the nanocapsules (size and membrane thickness of the polymeric shell), whereas the insertion of polysaccharides enables to tune the (bio)degradability of the nanocapsules. Shell-functionalized and/or core-loaded capsules could also be achieved in a similar one-pot process, by introducing a drug and/or biotin in the organic and aqueous phase, respectively.
•Two modules of 66 cells were aged with two EV cycling protocols.•Free ageing signals (U,I) were used to determine the quasi-EIS (QEIS) spectra.•These QEIS spectra were fitted with an equivalent ...circuit model.•The fitted parameters were used to develop a tool to estimate the battery SoH.•This tool shows good accuracy in the estimation of SoH (2% uncertainty).
The development of improved State-of-Health (SoH) diagnostic methods is a current research topic for battery-powered applications. For instance, the current rapid development of Electric Vehicles (EV) creates a strong demand for an accurate and reliable on-board SoH indicator during operation. Such an indicator is a key parameter required to optimize battery energy management and to track the degradation of the system performance. The electrochemical impedance spectrum (EIS) of an electrochemical system is a powerful lab-based diagnostic technique, usually measured using a frequency response analyzer. In this paper, we present an innovative diagnostic technique based on analysis of free voltage and current signals to give a so called “quasi-electrochemical impedance spectrum” (QEIS) and demonstrate its application on a Li-ion battery during a real EV duty cycle. It is worth noting that in our technique no additional signal is applied to the cell, since the current flowing into cells during use on-board is directly processed in the data treatment step.
Commercial batteries (1.4Ah cylindrical LiFePO4/graphite cell) were selected in this study to validate the diagnostic method in the framework of an applied case study related to an electric school bus demonstrator. In order to study the capability of QEIS measurements as a diagnostic tool for SoH of Li-ion cells, a test procedure including ageing phases has been defined to characterise Li-ion cells before and during ageing. Voltage and current signals were treated by Fast Fourier Transform (FFT) in order to determine the QEIS spectra of Li-ion cells under study. Then, SoH prediction algorithms have been obtained from a mathematical analysis of the impedance parameters sensitive to SoH.
Front Cover: Article 2200168 by Senbin Chen, Jintao Zhu, and co‐workers summarizes the design and synthetic routes towards Hydrogenbonded nanomedicines, focuses on the growing understanding of the ...structure‐function relationship for efficient cancer treatment. A guidance for designing new Hydrogen‐bonded intelligent theranostic agents is proposed, to inspire more successful explorations of cancer nanotheranostics and finally to promote potential clinical translations.
Stable monodisperse poly(vinyl acetate) (PVAc) submicronic latex particles were synthesized by ab initio batch emulsion polymerization using a dextran derivative from renewable resource as an ...efficient steric stabilizer. The dextranend-functionalized by a xanthate moiety was synthesized by Huisgen's 1,3-dipolar cycloaddition (click chemistry). It was applied as a macromolecular RAFT (reversible addition fragmentation chain transfer) agent in surfactant-free emulsion polymerization of vinyl acetate to form in situ an amphiphilic block copolymer able to efficiently stabilize the latex particles. The method afforded the preparation of high solids content (27%) latices coated by dextran. Both the kinetic study and the molar mass analyses confirmed the involvement of the dithiocarbonate group in the emulsion polymerization process.
We produce nacre-like composites made of a soft thermoplastic elastomer matrix reinforced by alumina platelets, as a flexible and healable alternative to stiff brick-and-mortar materials while ...keeping their characteristic anisotropic microstructure. Materials are manufactured using step-wise deposition and subsequent controlled evaporation of a suspension containing the polymer and the platelets. Well-aligned microstructures loaded from 15 to 65 vol.% in alumina are obtained through hot-pressing densification of the resulting composites. Remarkably, by combining calorimetry and low-field nuclear magnetic resonance techniques, we emphasize that the polymer mobility decreases significantly in spite of a lower degree of cristallinity when the platelet content is increased. This result sheds light on the origin of the limited quality of samples above 45 vol.%, opening new research directions to improve the design of organic nacre-like composites. Tensile, bending and indentation tests on samples containing up to 45 vol.% in platelets are then used to rationalize the mechanical properties variation related to the polymer state. Finally, we show that the addition of 3 vol.% of Fe nanoparticles into the composites is enough to enable their induction heating that we aim to utilize in the future as a contactless healing method.
•Simple processing route for Nacre-like composites with a soft thermoplastic elastomer matrix.•Straightforward manufacturing of gradient microstructures, no specimen size limitation.•Induction heating can be used to stimulate healing with 3 vol.% of iron nanoparticles.•Innovative coupling of NMR and DSC enables to probe the polymer state within the composites.
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This work deals with the study of comb-like vs. arborescent grafted copolymers made of poly(chloroethyl vinyl ether)-
g-polystyrene (PCEVE-
g-PS). We describe how the molecular architecture of the ...branched polymers affects their nanoscale organization in thin films, as observed using atomic force microscopy. The results indicate that modifying the molecular architecture from a ‘generation-zero’ comb-like (PCEVE-
g-PS) to a ‘first-generation’ hyperbranched (PCEVE-
g-(PS-
b-PCEVE-
g-PS)) architecture strongly modifies the observed geometrical parameters of the molecules, in good agreement with the expected evolution of the molecular dimensions and the corresponding data obtained in solution.
The surface organization of the (PCEVE-
g-PS) copolymer molecules is also strongly conditioned by the interplay between the molecule–substrate interactions and the molecule–molecule interactions, leading to different possible orientations of the lateral branches with respect to the surface and thus to different final morphologies.
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