The Experts below are selected from a list of 1704 Experts worldwide ranked by ideXlab platform
Jean-luc Blin - One of the best experts on this subject based on the ideXlab platform.
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Investigation of a novel fluorinated surfactant-based system for the design of spherical wormhole-like mesoporous silica
Journal of Colloid and Interface Science, 2017Co-Authors: Philippe Riachy,, Melanie Emo, Marie-josé Stebe, Jean-luc Blin, Gerald Lopez, Bruno AmeduriAbstract:In contrast to hydrogenated based systems that led to many studies, fluorinated surfactants have been little reported. Thanks to their high chemical and thermal stability, these compounds are considered as suitable candidates for the synthesis of porous materials with an enhanced hydrothermal stability. This study reports the synthesis of a new fluorinated surfactant, 2-trifluoromethyl-7,7,8,8,9,9,10,10,11, 11,12,12,12-tridecafluoro-4-thia-1-dodecanoic acid (FSC) obtained from the thiol-ene radical addition of 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanethiol onto 2-trifluoromethyl acrylic acid in 85% yield. In the aim of achieving micelles in water to design mesoporous materials according to the cooperative templating mechanism, FSC was modified with water-soluble telechelic diamine (Jeffamine) ED-600. The modified surfactant was deeply characterized by spectroscopic methods and the FSC-Jeffamine ED-600 micellar system was used as porogen to prepare mesoporous materials via the cooperative templating mechanism. Spherical wormhole-like mesostructured silica materials of high specific surface area (850 m2/g) and homogeneous pore size distribution (ca. 3.4 nm) were obtained by conveniently adjusting the porogen/silica molar ratio and the hydrothermal conditions.
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Metastable micelles and true liquid crystal behaviour of newly designed "cataniomeric'' surfactants
Soft Matter, 2013Co-Authors: Melanie Emo, Marie-josé Stebe, Jean-luc Blin, Andreea PascAbstract:Jeffamines were used as molecular tools for the design of novel organized molecular systems based on so-called ``cataniomeric'' surfactants, which combine features of ionic liquids (ILs) and catanionic surfactants and which contain oligomeric building blocks. These systems show an original self-assembling behaviour in water, with a rich polymorphism: dynamic (or metastable) micelles and liquid crystals (cubic Im3m and Fm3m and hexagonal H-1 phases). ``Cataniomeric'' surfactants were prepared by a simple acid-base reaction between oligomeric Jeffamine ED900 and various fatty acids (lauric, myristic, stearic and oleic acid) in a stoichiometric ratio, similar to well known salt-free catanionic surfactants. The phase behaviour was rationalized in terms of hydrocarbon chain length of the fatty counterion (equivalent carbon atoms, ECN) and of headgroup electrostatic interactions and flexibility. All synthesized surfactants show a direct micellar cubic phase, whose stability increases with hydrophobicity. A transition to a hexagonal phase takes place when ECN is higher than 29, and thus independently of the symmetry of the molecule. Thermal stability of the hexagonal phase also increases with ECN. An epitaxial transition of H-1 -> Im3m -> Fm3m was also evidenced. These novel systems have straightforward applications in modern formulations or smart nanodevices, reversibly responsive to external stimuli.
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Solubilization of decane into gemini surfactant with a modified Jeffamine backbone: Design of hierarchical porous silica
Microporous and Mesoporous Materials, 2013Co-Authors: Anna May-masnou, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Abstract Herein, we have investigated the solubilization of decane into a novel nonionic gemini surfactant, myristoyl-end capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). Starting from this system, porous silica materials have been prepared. Performing the hydrothermal treatment at low temperature, a slight increase of the mesopore diameter is observed in the presence of decane. Increasing the temperature of the hydrothermal treatment, no swelling effect of decane is detected. By contrast, the pore diameter decreases but better mesopore homogeneity and a larger wall thickness are obtained. At high decane concentration the new myristoyl-end capped Jeffamine/decane/water system forms oil-in-water emulsions, which are used as template for the formation of hierarchical porous silica materials.
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Tailored Jeffamine Molecular Tools for Ordering Mesoporous Silica
Langmuir : the ACS journal of surfaces and colloids, 2012Co-Authors: A. May, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Herein, we report the formation of organized mesoporous silica materials prepared from a novel nonionic gemini surfactant, myristoyl-end-capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). The behavior of the modified Jeffamine in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The structure of the micelles was investigated from the SAXS and the analysis by generalized indirect Fourier transformation, which show that the particles are globular of core-shell type. The myristoyl chains, located at the ends of the amphiphile molecule, are assembled to form the core of the micelles and, as a consequence, the molecules are folded over on themselves. Mesoporous materials were then synthesized from the self-assembly mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that by modifying the synthesis parameters, such as the surfactant/silica precursor molar ratio and the hydrothermal conditions, one can control the size and the nanostructuring of the resulting material. It was observed that, the lower the temperature of the hydrothermal treatment, the better the mesopore ordering.
Luc Picton - One of the best experts on this subject based on the ideXlab platform.
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Thermo-controlled rheology of electro-assembled polyanionic polysaccharide (alginate) and polycationic thermo-sensitive polymers.
Carbohydrate polymers, 2015Co-Authors: Pape Momar Niang, Virginie Dulong, Didier Le Cerf, Zhiwei Huang, Zied Souguir, Luc PictonAbstract:Several thermo-sensitive polyelectrolyte complexes were prepared by ionic self-association between an anionic polysaccharide (alginate) and a monocationic copolymer (polyether amine, Jeffamine®-M2005) with a 'Low Critical Solubility Temperature' (LCST). We show that electro-association must be established below the aggregation temperature of the free Jeffamine®, after which the organization of the system is controlled by the thermo-association of Jeffamine® that was previously electro-associated with the alginate. Evidence for this comes primarily from the rheology in the semi-dilute region. Electro- and thermo-associative behaviours are optimal at a pH corresponding to maximum ionization of both compounds (around pH 7). High ionic strength could prevent the electro-association. The reversibility of the transition is possible only at temperatures lower than the LCST of Jeffamine®. Similar behaviour has been obtained with carboxymethyl cellulose (CMC), which suggests that this behaviour can be observed using a range of anionic polyelectrolytes. In contrast, no specific properties have been found for pullulan, which is a neutral polysaccharide.
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Pullulan-Based Polymer Surfactants for Vinyl Acetate Miniemulsion Polymerization: Kinetics and Colloidal Stability Investigations
Macromolecular Chemistry and Physics, 2015Co-Authors: Sabrina Belbekhouche, Luc Picton, Didier Le Cerf, Thierry HamaideAbstract:Various pullulan-b-Jeffamine block copolymers (Jeffamine is a PEO-b-PPO copolymer (PEO = poly(ethylene oxide), PPO = poly(propylene oxide)) are used as surfactants for vinyl acetate miniemulsion polymerization. Their influence on the kinetics, average molecular weights and colloidal stability, is compared with that of Pluronic F68, when using either organosoluble or hydrosoluble initiators. In the first case, conversions and molecular weights are not affected by the polymer surfactant, in contrast to what is observed when using the hydrosoluble system, that may be due to a reaction between the incoming radicals and the sugar units of the pullulan chain. Long-term colloidal stability between 4 degrees C and 40 degrees C over more than 4 months is observed and is not affected by the addition of salts when using pullulan-based surfactant.
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New anionic crosslinked multi-responsive pullulan hydrogels
Carbohydrate Polymers, 2012Co-Authors: G. Mocanu, Doina Mihai, Virginie Dulong, Luc Picton, Didier Le CerfAbstract:Abstract The paper studies the synthesis and characterization of anionic thermoassociative carboxymethylpullulan hydrogels through crosslinking of carboxymethylpullulan with two difunctional Jeffamines: ED-600 and ED-2003; taking into account that the Jeffamines contain polyoxyalkyleneamines (polyethylene oxide, polypropylene oxide) backbone with thermoassociative properties, is expected that the polysaccharide-Jeffamine derivatives also possess amphiphilic and thermosensitive characteristics. The hydrogels were characterized through FTIR spectra, swelling behavior in various media, at various pH or temperatures, retention of hydrophobic molecules, to appreciate their polyelectrolyte and thermoassociative properties. The interaction with biomolecules as proteins: lysozyme and BSA and as antioxidants: lutein was studied to estimate some potential application domains of these newly synthesized hydrogels.
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New anionic amphiphilic thermosensitive pullulan derivatives
Carbohydrate Polymers, 2011Co-Authors: G. Mocanu, Doina Mihai, Virginie Dulong, Luc Picton, Didier LecerfAbstract:Abstract New anionic amphiphilic thermosensitive pullulan derivatives have been synthesized through reaction of carboxymethylpullulan (CMP) with two Jeffamine ® differing by their molecular weight (Jeff M2005 and Jeff M600). The structure of the derivatives was confirmed through FTIR and 1 H NMR spectra. Their physico-chemical behavior has been studied through viscometric, fluorescence measurements, which evidenced the amphiphilic, thermosensitive character of these derivatives. The physico chemical characteristics of the synthesized pullulan derivatives depend on the Jeffamine used and on the degree of substitution with Jeffamine units introduced.
Marie-josé Stebe - One of the best experts on this subject based on the ideXlab platform.
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Investigation of a novel fluorinated surfactant-based system for the design of spherical wormhole-like mesoporous silica
Journal of Colloid and Interface Science, 2017Co-Authors: Philippe Riachy,, Melanie Emo, Marie-josé Stebe, Jean-luc Blin, Gerald Lopez, Bruno AmeduriAbstract:In contrast to hydrogenated based systems that led to many studies, fluorinated surfactants have been little reported. Thanks to their high chemical and thermal stability, these compounds are considered as suitable candidates for the synthesis of porous materials with an enhanced hydrothermal stability. This study reports the synthesis of a new fluorinated surfactant, 2-trifluoromethyl-7,7,8,8,9,9,10,10,11, 11,12,12,12-tridecafluoro-4-thia-1-dodecanoic acid (FSC) obtained from the thiol-ene radical addition of 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanethiol onto 2-trifluoromethyl acrylic acid in 85% yield. In the aim of achieving micelles in water to design mesoporous materials according to the cooperative templating mechanism, FSC was modified with water-soluble telechelic diamine (Jeffamine) ED-600. The modified surfactant was deeply characterized by spectroscopic methods and the FSC-Jeffamine ED-600 micellar system was used as porogen to prepare mesoporous materials via the cooperative templating mechanism. Spherical wormhole-like mesostructured silica materials of high specific surface area (850 m2/g) and homogeneous pore size distribution (ca. 3.4 nm) were obtained by conveniently adjusting the porogen/silica molar ratio and the hydrothermal conditions.
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Metastable micelles and true liquid crystal behaviour of newly designed "cataniomeric'' surfactants
Soft Matter, 2013Co-Authors: Melanie Emo, Marie-josé Stebe, Jean-luc Blin, Andreea PascAbstract:Jeffamines were used as molecular tools for the design of novel organized molecular systems based on so-called ``cataniomeric'' surfactants, which combine features of ionic liquids (ILs) and catanionic surfactants and which contain oligomeric building blocks. These systems show an original self-assembling behaviour in water, with a rich polymorphism: dynamic (or metastable) micelles and liquid crystals (cubic Im3m and Fm3m and hexagonal H-1 phases). ``Cataniomeric'' surfactants were prepared by a simple acid-base reaction between oligomeric Jeffamine ED900 and various fatty acids (lauric, myristic, stearic and oleic acid) in a stoichiometric ratio, similar to well known salt-free catanionic surfactants. The phase behaviour was rationalized in terms of hydrocarbon chain length of the fatty counterion (equivalent carbon atoms, ECN) and of headgroup electrostatic interactions and flexibility. All synthesized surfactants show a direct micellar cubic phase, whose stability increases with hydrophobicity. A transition to a hexagonal phase takes place when ECN is higher than 29, and thus independently of the symmetry of the molecule. Thermal stability of the hexagonal phase also increases with ECN. An epitaxial transition of H-1 -> Im3m -> Fm3m was also evidenced. These novel systems have straightforward applications in modern formulations or smart nanodevices, reversibly responsive to external stimuli.
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Solubilization of decane into gemini surfactant with a modified Jeffamine backbone: Design of hierarchical porous silica
Microporous and Mesoporous Materials, 2013Co-Authors: Anna May-masnou, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Abstract Herein, we have investigated the solubilization of decane into a novel nonionic gemini surfactant, myristoyl-end capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). Starting from this system, porous silica materials have been prepared. Performing the hydrothermal treatment at low temperature, a slight increase of the mesopore diameter is observed in the presence of decane. Increasing the temperature of the hydrothermal treatment, no swelling effect of decane is detected. By contrast, the pore diameter decreases but better mesopore homogeneity and a larger wall thickness are obtained. At high decane concentration the new myristoyl-end capped Jeffamine/decane/water system forms oil-in-water emulsions, which are used as template for the formation of hierarchical porous silica materials.
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Tailored Jeffamine Molecular Tools for Ordering Mesoporous Silica
Langmuir : the ACS journal of surfaces and colloids, 2012Co-Authors: A. May, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Herein, we report the formation of organized mesoporous silica materials prepared from a novel nonionic gemini surfactant, myristoyl-end-capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). The behavior of the modified Jeffamine in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The structure of the micelles was investigated from the SAXS and the analysis by generalized indirect Fourier transformation, which show that the particles are globular of core-shell type. The myristoyl chains, located at the ends of the amphiphile molecule, are assembled to form the core of the micelles and, as a consequence, the molecules are folded over on themselves. Mesoporous materials were then synthesized from the self-assembly mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that by modifying the synthesis parameters, such as the surfactant/silica precursor molar ratio and the hydrothermal conditions, one can control the size and the nanostructuring of the resulting material. It was observed that, the lower the temperature of the hydrothermal treatment, the better the mesopore ordering.
Michel Armand - One of the best experts on this subject based on the ideXlab platform.
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Lowering the operational temperature of all-solid-state lithium polymer cell with highly conductive and interfacially robust solid polymer electrolytes
Journal of Power Sources, 2018Co-Authors: Itziar Aldalur, Heng Zhang, Michal Piszcz, Lide M. Rodriguez-martinez, Maria Martinez‐ibañez, Michel ArmandAbstract:Abstract Novel solid polymer electrolytes (SPEs), comprising of comb polymer matrix grafted with soft and disordered polyether moieties (Jeffamine®) and lithium bis(fluorosulfonyl)imide (LiFSI) are investigated in all-solid-state lithium metal (Li°) polymer cells. The LiFSI/Jeffamine-based SPEs are fully amorphous at room temperature with glass transitions as low as ca. −55 °C. They show higher ionic conductivities than conventional poly(ethylene oxide) (PEO)-based SPEs at ambient temperature region, and good electrochemical compatibility with Li° electrode. These exceptional properties enable the operational temperature of Li° | LiFePO4 cells to be decreased from an elevated temperature (70 °C) to room temperature. Those results suggest that LiFSI/Jeffamine-based SPEs can be promising electrolyte candidates for developing safe and high performance all-solid-state Li° batteries.
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Jeffamine® based polymers as highly conductive polymer electrolytes and cathode binder materials for battery application
Journal of Power Sources, 2017Co-Authors: Itziar Aldalur, Heng Zhang, Michal Piszcz, Uxue Oteo, Lide M. Rodriguez-martinez, Devaraj Shanmukaraj, Teófilo Rojo, Michel ArmandAbstract:Abstract We report a simple synthesis route towards a new type of comb polymer material based on polyether amines oligomer side chains (i.e., Jeffamine® compounds) and a poly(ethylene-alt-maleic anhydride) backbone. Reaction proceeds by imide ring formation through the NH2 group allowing for attachment of side chains. By taking advantage of the high configurational freedoms and flexibility of propylene oxide/ethylene oxide units (PO/EO) in Jeffamine® compounds, novel polymer matrices were obtained with good elastomeric properties. Fully amorphous solid polymer electrolytes (SPEs) based on lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and Jeffamine®-based polymer matrices show low glass transition temperatures around −40 °C, high ionic conductivities and good electrochemical stabilities. The ionic conductivities of Jeffamine-based SPEs (5.3 × 10−4 S cm−1 at 70 °C and 4.5 × 10−5 S cm−1 at room temperature) are higher than those of the conventional SPEs comprising of LiTFSI and linear poly(ethylene oxide) (PEO), due to the amorphous nature and the high concentration of mobile end-groups of the Jeffamine-based polymer matrices rather than the semi-crystalline PEO The feasibility of Jeffamine-based compounds in lithium metal batteries is further demonstrated by the implementation of Jeffamine®-based polymer as a binder for cathode materials, and the stable cycling of Li|SPE|LiFePO4 and Li|SPE|S cells using Jeffamine-based SPEs.
Andreea Pasc - One of the best experts on this subject based on the ideXlab platform.
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Metastable micelles and true liquid crystal behaviour of newly designed "cataniomeric'' surfactants
Soft Matter, 2013Co-Authors: Melanie Emo, Marie-josé Stebe, Jean-luc Blin, Andreea PascAbstract:Jeffamines were used as molecular tools for the design of novel organized molecular systems based on so-called ``cataniomeric'' surfactants, which combine features of ionic liquids (ILs) and catanionic surfactants and which contain oligomeric building blocks. These systems show an original self-assembling behaviour in water, with a rich polymorphism: dynamic (or metastable) micelles and liquid crystals (cubic Im3m and Fm3m and hexagonal H-1 phases). ``Cataniomeric'' surfactants were prepared by a simple acid-base reaction between oligomeric Jeffamine ED900 and various fatty acids (lauric, myristic, stearic and oleic acid) in a stoichiometric ratio, similar to well known salt-free catanionic surfactants. The phase behaviour was rationalized in terms of hydrocarbon chain length of the fatty counterion (equivalent carbon atoms, ECN) and of headgroup electrostatic interactions and flexibility. All synthesized surfactants show a direct micellar cubic phase, whose stability increases with hydrophobicity. A transition to a hexagonal phase takes place when ECN is higher than 29, and thus independently of the symmetry of the molecule. Thermal stability of the hexagonal phase also increases with ECN. An epitaxial transition of H-1 -> Im3m -> Fm3m was also evidenced. These novel systems have straightforward applications in modern formulations or smart nanodevices, reversibly responsive to external stimuli.
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Solubilization of decane into gemini surfactant with a modified Jeffamine backbone: Design of hierarchical porous silica
Microporous and Mesoporous Materials, 2013Co-Authors: Anna May-masnou, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Abstract Herein, we have investigated the solubilization of decane into a novel nonionic gemini surfactant, myristoyl-end capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). Starting from this system, porous silica materials have been prepared. Performing the hydrothermal treatment at low temperature, a slight increase of the mesopore diameter is observed in the presence of decane. Increasing the temperature of the hydrothermal treatment, no swelling effect of decane is detected. By contrast, the pore diameter decreases but better mesopore homogeneity and a larger wall thickness are obtained. At high decane concentration the new myristoyl-end capped Jeffamine/decane/water system forms oil-in-water emulsions, which are used as template for the formation of hierarchical porous silica materials.
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Tailored Jeffamine Molecular Tools for Ordering Mesoporous Silica
Langmuir : the ACS journal of surfaces and colloids, 2012Co-Authors: A. May, Marie-josé Stebe, Andreea Pasc, J. M. Gutiérrez, M. Porras, Jean-luc BlinAbstract:Herein, we report the formation of organized mesoporous silica materials prepared from a novel nonionic gemini surfactant, myristoyl-end-capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). The behavior of the modified Jeffamine in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The structure of the micelles was investigated from the SAXS and the analysis by generalized indirect Fourier transformation, which show that the particles are globular of core-shell type. The myristoyl chains, located at the ends of the amphiphile molecule, are assembled to form the core of the micelles and, as a consequence, the molecules are folded over on themselves. Mesoporous materials were then synthesized from the self-assembly mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that by modifying the synthesis parameters, such as the surfactant/silica precursor molar ratio and the hydrothermal conditions, one can control the size and the nanostructuring of the resulting material. It was observed that, the lower the temperature of the hydrothermal treatment, the better the mesopore ordering.