References of "Detrembleur, Christophe"
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See detailPrecision design of novel bio-based and ethylene-based copolymers: application to advanced nanocomposites
Scholten, Philip ULiege; Detrembleur, Christophe ULiege; Meier, Michaël et al

Conference (2016, March 18)

Polyolefins are an inexpensive class of compounds that can be used to prepare a plethora of different materials. Poly(ethylene) is the worldwide most produced polymer and is mostly synthesised by free ... [more ▼]

Polyolefins are an inexpensive class of compounds that can be used to prepare a plethora of different materials. Poly(ethylene) is the worldwide most produced polymer and is mostly synthesised by free radical polymerisation or catalytic coordination insertion using high temperature and pressure. The controlled radical polymerisation of ethylene is very difficult to achieve because of secondary reactions of this unconjugated monomer, e.g. chain transfer and termination reactions. Cobalt-mediated radical polymerisation (CMRP) represents a solution to control its polymerisation in mild conditions: in a reversible deactivation mechanism, a cobalt complex reversibly traps the active growing chains and converts them into dormant species, avoiding side reactions and allowing for a controlled polymerisation. Using CMRP, statistical copolymers of ethylene and vinyl acetate (VAc) have been synthesised, as well as block-like and block copolymers. Furthermore, functionalisation of the α- and ω-chain ends are now possible. Incorporating other monomers, e.g. vinyl esters or vinyl amides, into an ethylene copolymer by CMRP will lead to completely new and highly interesting materials which may act as compatibilisers for the dispersion of natural polymers, such as cellulose, into various polymer matrices. The goal of this work is to design novel well-defined functional polyethylenes that are expected to improve the dispersion of natural polymers into polyolefins. [less ▲]

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See detailTheoretical study of the organocatalyzed synthesis of NIPUs
Alves, Margot ULiege; Méreau, Raphaël; Grignard, Bruno ULiege et al

Poster (2016, March)

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See detailCobalt-mediated radical polymerization of vinyl acetate and acrylonitrile in supercritical carbon dioxide
Kermagoret; Chau, Ngoc Do Quyen; Grignard, Bruno ULiege et al

in Macromolecular Rapid Communications (2016), 39(6), 539-544

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) is successfully achieved in supercritical carbon dioxide (scCO 2 ). CMRP of VAc is conducted using an alkyl-cobalt(III) adduct that is ... [more ▼]

Cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) is successfully achieved in supercritical carbon dioxide (scCO 2 ). CMRP of VAc is conducted using an alkyl-cobalt(III) adduct that is soluble in scCO2 . Kinetics studies coupled to visual observations of the polymerization medium highlight that the melt viscosity and PVAc molar mass ( Mn ) are key parameters that affect the CMRP in scCO2. It is noticed that CMRP is controlled for M n up to 10 000 g mol−1 , but loss of control is progressively observed for higher molar masses when PVAc precipitates in the polymerization medium. Low molar mass PVAc macroinitiator, prepared by CMRP in scCO2 , is then successfully used to initiate the acrylonitrile polymerization. PVAc-b-PAN block copolymer is collected as a free flowing powder at the end of the process although the dispersity of the copolymer increases with the reaction time. Although optimization is required to decrease the dispersity of the polymer formed, this CMRP process opens new perspectives for macromolecular engineering in scCO2 without the utilization of fluorinated comonomers or organic solvents. [less ▲]

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See detailProcessing of a new class of multifunctional hybrid for electromagnetic absorption based on a foam filled honeycomb
Bollen, Pierre; Quievy, Nicolas; Detrembleur, Christophe ULiege et al

in Materials & Design (2016), 89

A multifunctional hybrid material class in the form of a sandwich panel has been developed towards the com- bined optimization of mechanical and electromagnetic absorption performance. The faces of the ... [more ▼]

A multifunctional hybrid material class in the form of a sandwich panel has been developed towards the com- bined optimization of mechanical and electromagnetic absorption performance. The faces of the panel are made of glass fibre reinforced epoxy composites and the core is made of carbon nanotube reinforced polymer foam filling a metallic honeycomb. The different processing strategies and options tested to fabricate the core material are described aswell as the associated scientific and technological issues. The most efficient processing route is by foaming the nanocomposite with a chemical foaming agent directly inside the honeycomb. This route offers a good surface finish and the operation can be achieved in one step. But, in order to produce large panels with a semi-continuous process, thermo-mechanical insertion of the foamed nanocomposite with supercritical CO2 can be more suitable. The characterization of the electromagnetic absorption of the panels produced by dif- ferent routes shows that the performance is not much sensitive to processing defects making possible upscaling to mass production. [less ▲]

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See detailOne-pot synthesis of double poly(ionic liquid) block copolymers by cobalt-mediated radical polymerization-induced self assembly (CMR-PISA) in water
Cordella, Daniela ULiege; Debuigne, Antoine ULiege; Jérôme, Christine ULiege et al

in Macromolecular Rapid Communications (2016), 37(14), 1181-1187

Amphiphilic double poly(ionic liquid) (PIL) block copolymers are directly prepared by cobalt- mediated radical polymerization induced self-assembly (CMR-PISA) in water of N-vinyl imida- zolium monomers ... [more ▼]

Amphiphilic double poly(ionic liquid) (PIL) block copolymers are directly prepared by cobalt- mediated radical polymerization induced self-assembly (CMR-PISA) in water of N-vinyl imida- zolium monomers carrying distinct alkyl chains. The cobalt-mediated radical polymerization of N-vinyl-3-ethyl imidazolium bromide (VEtImBr) is first carried out until high conversion in water at 30 °C, using an alkyl bis(acetylacetonate)cobalt(III) adduct as initiator and con- trolling agent. The as-obtained hydrophilic poly(N-vinyl-3- ethyl imidazolium bromide) (PVEtImBr) is then used as a macroinitiator for the CMR-PISA of N-vinyl-3-octyl imidazo- lium bromide (VOcImBr). Self-assembly of the amphiphilic PVEtImBr-b-PVOcImBr block copolymer, i.e., of PIL-b-PIL-type, rapidly takes place in water, forming polymer nanoparticles consisting of a hydrophilic PVEtImBr corona and a hydro- phobic PVOcImBr core. Preliminary investigation into the effect of the size of the hydrophobic block on the dimension of the nanoparticles is also described. [less ▲]

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See detailUnexpected LCST-type phase behaviour of a poly(vinyl thiazolium) polymer in acetone
Grygiel, Konrad; Zhang, Weiyi; Detrembleur, Christophe ULiege et al

in RSC Advances (2016), 6(62), 57117-57121

We report on an unexpected lower critical solution temperature (LCST)-type phase transition of a poly(vinyl thiazolium) polymer in acetone solution, which was synthesized via radical polymerization of its ... [more ▼]

We report on an unexpected lower critical solution temperature (LCST)-type phase transition of a poly(vinyl thiazolium) polymer in acetone solution, which was synthesized via radical polymerization of its corresponding ionic monomer bearing no thermoresponsiveness in acetone. The phase transition temperature can be conveniently varied by polymer concentration, ionic strength and addition of a cosolvent. [less ▲]

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See detailA comprehensive density functional theory study of the key role of fluorination and dual hydrogen bonding in the activation of the epoxide/CO2 coupling by fluorinated alcohols
Alves, Margot ULiege; Méreau, Raphaël; Grignard, Bruno ULiege et al

in RSC Advances (2016), 6(43), 36327-36335

The activation mechanism of the CO2/propylene oxide coupling catalysed by a bicomponent organocatalyst combining the use of TBABr with (multi)phenolic or fluorinated hydrogen bond donors (HBDs) was ... [more ▼]

The activation mechanism of the CO2/propylene oxide coupling catalysed by a bicomponent organocatalyst combining the use of TBABr with (multi)phenolic or fluorinated hydrogen bond donors (HBDs) was investigated using the Density Functional Theory (DFT). Thus, it was shown that increasing the number of electron withdrawing trifluoromethyl substituents in HBDs strengthens their proton donor capability and allows a better stabilization by hydrogen bonding of the intermediates and transition states. In addition, the high efficiency of fluorinated monoalcohol activators is related to a dual hydrogen bonding mechanism by two fluorinated molecules that cooperatively contribute to the CO2/propylene oxide coupling. [less ▲]

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See detailFast Atmospheric Plasma Deposition of Bio-Inspired Catechol/Quinone-Rich Nanolayers to Immobilize NDM-1 Enzymes for Water Treatment
Mauchauffé, Rodolphe; Bonot, Sébastien; Moreno-Couranjou, Maryline et al

in Advanced Materials Interfaces (2016), 3(8), 101002

Detailed reference viewed: 36 (8 ULiège)
See detailOrganocatalytic coupling of carbon dioxide with epoxides: the unexpected booster effect of fluoroalcohols
Grignard, Bruno ULiege; Gennen, Sandro ULiege; Alves, Margot ULiege et al

Poster (2015, December 19)

Valorising CO2 as a C1 feedstock for producing added value building blocks is seducing as it is a free and in exhaustive waste resulting from human activity. Carbon dioxide is a thermodynamically and ... [more ▼]

Valorising CO2 as a C1 feedstock for producing added value building blocks is seducing as it is a free and in exhaustive waste resulting from human activity. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into cyclic carbonates by coupling with epoxides. Cyclic carbonates are valuable products that find applications as solvents, electrolytes or as monomers for polyurethanes synthesis. Although the CO2/epoxide coupling reaction has been extensively studied, the development of organocatalysts that are highly efficient under mild experimental conditions still remains a challenge. Onium salts are the most common catalysts that show reasonable catalytic activity at high pressure (> 100 bars) and high temperature (> 100°C) only. Fortunately, the efficiency of these organocatalysts can be improved by addition of appropriate hydrogen bond donors activators (HBD). In this talk, we will report the development of a new highly efficient catalytic platform consisting in an onium halide salt combined with HBD activators for the fast and solvent-free synthesis of cyclic carbonates by coupling CO2 with epoxides. The cocatalytic effect of series of HBDs will be demonstrated by detailed online kinetics studies under pressure using Raman or IR spectroscopy. We will show that our new organocatalytic platform facilitates the fast conversion of epoxy groups into cyclic carbonates under mild experimental conditions, and can be easily implemented to the modification of epoxidized vegetable oils. The synergistic effects between HBDs and onium salt will be highlighted by a detailed mechanistic study of the reaction through DFT calculations. [less ▲]

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See detailOrganometallic-mediated radical polymerization, a versatile tool for the precision synthesis of unprecedented copolymers
Detrembleur, Christophe ULiege; Cordella, Daniela ULiege; Demarteau, Jérémy ULiege et al

Conference (2015, December 17)

Controlled radical polymerization techniques give access to innovative (multi)functional polymeric materials for advanced applications. Organometallic-mediated radical polymerization (OMRP) is one of ... [more ▼]

Controlled radical polymerization techniques give access to innovative (multi)functional polymeric materials for advanced applications. Organometallic-mediated radical polymerization (OMRP) is one of these techniques that enable the preparation of unprecedented copolymers, and is based on the temporary deactivation of the propagating chains by a transition metal complex. The strength of the carbon-metal bond at the polymer chain-end is dictating the reactivity of the system. One of the most efficient OMRP process involves the commercially available Co(acac)2. Recent studies have demonstrated that the system reactivity is easily modulated by the addition of some molecules able to coordinate the cobalt complex, by tuning the temperature, or by UV irradiation. The facile modulation of the C-Co bond strength has enabled to control the polymerization of monomers of opposite reactivity, such as vinyl esters and acrylates, and to synthesize novel well-defined (co)polymers under very mild experimental conditions. In this talk, we will discuss some recent breakthroughs in the field that illustrate the huge potential of the process for the design of unique functional macromolecules. More precisely, we will describe the first control of the copolymerization of ethylene with a series of functional vinyl monomers under mild experimental conditions that leads to random copolymers with ethylene content up to 60 mol% and negligible chain branching. The first one-pot synthesis of novel ethylene-based block copolymers will also be discussed. Additionally, we will demonstrate the implementation of the OMRP process to aqueous based media by describing, amongst other examples, the precision synthesis of innovative functional (telechelic) poly(ionic liquid)s (PILs) in water. [less ▲]

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See detailNovel organocobalt based on acetylacetonate ligands for the precision synthesis of telechelic polymers
Demarteau, Jérémy ULiege; Cordella, Daniela ULiege; Kermagoret, Anthony et al

Conference (2015, December 17)

Organocobalt(III) with acetylacetonate ligands is the most representative example of R-Co bearing a weak C-Co bond that can release alkyl radicals under mild experimental conditions without requiring a ... [more ▼]

Organocobalt(III) with acetylacetonate ligands is the most representative example of R-Co bearing a weak C-Co bond that can release alkyl radicals under mild experimental conditions without requiring a photoactivation. The unique isolated specimen is a short oligo(vinyl acetate) end-capped by Co(acac)2. The high lability of the C-Co bond of this R-Co combined to the unique capacity of Co(acac)2 to reversibly trap alkyl radicals make this organocobalt unique for the precision synthesis of unprecedented polymers by the so-called Cobalt-Mediated Radical Polymerization (CMRP) technique. The growth of unstabilized and highly reactive growing radicals formed by the addition of R· to unconjugated olefins (vinyl esters, vinyl amides, vinyl imidazolium, vinyl chloride, ethylene) is controlled by the reversible formation of a weak C-Co bond at the polymer chain end. The lack of alternatives to this R-Co, especially to the structure of the alkyl group, has placed limitations on further innovation in (macro)molecular design. Other functional variants that would enable attractive chain-end derivatizations are unfortunately not available. In this communication, we will address this important challenge by describing an innovative synthetic route towards the preparation of a new functional R-Co(acac)2 that are characterized by a weak C-Co bond. We will report the conditions required for initiating and controlling the radical polymerization of various monomers from these R-Co. We will also demonstrate their utility for the production of novel telechelic polymers under mild experimental conditions, syntheses that can be carried out in water. [less ▲]

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See detailExperimental and computational micro–mechanical investigations of compressive properties of polypropylene/multi–walled carbon nanotubes nanocomposite foams
Wan, Fangyi; Tran, Minh Phuong; Leblanc, Christophe ULiege et al

in Mechanics of Materials (2015), 91(Part 1), 95-118

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of ... [more ▼]

The compressive behavior of nanocomposite foams is studied by both experimental and computational micro-mechanics approaches with the aim of providing an efficient computational model for this kind of material. The nanocomposites based on polypropylene (PP) and different contents of multi-walled carbon nanotubes (CNTs) are prepared by melt mixing method. The nanocomposite samples are foamed using super-critical carbon dioxide (ScCO2) as blowing agent at different soaking temperatures. The influence of this foaming parameter on the morphological characteristics of the foam micro-structure is discussed. Differential Scanning Calorimetry (DSC) measurements are used to quantify the crystallinity degree of both nanocomposites and foams showing that the crystallinity degree is reduced after the foaming process. This modification leads to mechanical properties of the foam cell walls that are different from the raw nanocomposite PP/CNTs material. Three--point bending tests are performed on the latter to measure the flexural modulus in terms of the crystallinity degree. Uniaxial compression tests are then performed on the foamed samples under quasi-static conditions in order to extract the macro-scale compressive response. Next, a two-level multi-scale approach is developed to model the behavior of the foamed nanocomposite material. On the one hand, the micro-mechanical properties of nanocomposite PP/CNTs cell walls are evaluated from a theoretical homogenization model accounting for the micro-structure of the semi-crystalline PP, for the degree of crystallinity, and for the CNT volume fraction. The applicability of this theoretical model is demonstrated via the comparison with experimental data from the described experimental measurements and from literature. On the other hand, the macroscopic behavior of the foamed material is evaluated using a computational micro-mechanics model using tetrakaidecahedron unit cells and periodic boundary conditions to estimate the homogenized properties. The unit cell is combined with several geometrical imperfections in order to capture the elastic collapse of the foamed material. The numerical results are compared to the experimental measurements and it is shown that the proposed unit cell computational micro-mechanics model can be used to estimate the homogenized behavior, including the linear and plateau regimes, of nanocomposite foams. [less ▲]

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See detailPrecision design of polymers via organometallic-mediated radical polymerization of 'less activated' vinyl monomers
Debuigne, Antoine ULiege; Demarteau, Jérémy ULiege; Kermagoret, Anthony et al

Conference (2015, November 15)

Detailed reference viewed: 36 (17 ULiège)
See detailPolymer chemistry for theragnostics
Liu, Ji; Detrembleur, Christophe ULiege; Duguet, Etienne et al

Conference (2015, November)

Stimuli-responsive nano-materials have been playing increasingly important roles in the biomedical field due to their ability to adapt their physico-chemical properties in response to external stimuli ... [more ▼]

Stimuli-responsive nano-materials have been playing increasingly important roles in the biomedical field due to their ability to adapt their physico-chemical properties in response to external stimuli, such as temperature, pH, ionic strength, magnetic field, etc. Nanohybrids combining inorganic particles and stimuli-responsive polymers are particularly well-suited to develop advanced drug nanocarriers for targeted delivery and concomitant diagnostics. Based on the recent developments in controlled radical polymerization, especially cobalt-mediated radical polymerization, various hybrid nanostructures have been synthesized and tested as drug delivery systems able to trigger the drug release in response to dedicated environment conditions or external stimuli. Studies on cytotoxicity, cellular uptake and in vitro triggered release with cell culture will also highlight the potential of these new materials. [less ▲]

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See detailControlled radical cross-linking copolymerization
Weiss-Maurin; Detrembleur, Christophe ULiege; Taton, Daniel

Scientific conference (2015, October 22)

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See detailNew synthetic possibilities offered by organometallic-mediated radical polymerization
Debuigne, Antoine ULiege; Demarteau, Jérémy ULiege; Kermagoret, Anthony et al

Scientific conference (2015, October 08)

In the last years, considerable efforts have been devoted to the development of methods for controlling the radical polymerization of vinyl monomers and designing a large range of well-defined ... [more ▼]

In the last years, considerable efforts have been devoted to the development of methods for controlling the radical polymerization of vinyl monomers and designing a large range of well-defined macromolecular structures with specific properties. Although significant progress has been made, there is still room for improvements especially for the so-called ‘less activated’ monomers (LAMs) like vinyl esters, N-vinylamides, olefins, etc. This presentation aims to describe the potential of the Organometallic-Mediated Radical Polymerization (OMRP) for controlling the polymerization of these challenging monomers. Basic principles of OMRP will be presented as well as cutting edge developments in this field like the precision design of ethylene-vinyl acetate copolymers (EVAs) or the synthesis of novel alkylcobalt(III) species used as functional OMRP initiator for producing unique well-defined α-functional polymers. [less ▲]

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See detailHalomethyl-cobalt(bis-acetylacetonate) for the controlled synthesis of functional polymers
Demarteau, Jérémy ULiege; Kermagoret, Anthony; German, Ian et al

in Chemical Communications (2015), 51(76), 14334-14337

Novel organocobalt complexes featuring weak C–CoL2 bonds (L = acetylacetonate) are prepared and used as sources of halomethyl radicals. They permit the precision synthesis of a-halide functionalized and ... [more ▼]

Novel organocobalt complexes featuring weak C–CoL2 bonds (L = acetylacetonate) are prepared and used as sources of halomethyl radicals. They permit the precision synthesis of a-halide functionalized and telechelic polymers in organic media or in water. Substitution of halide by azide allows derivatization of polymers using the CuAAC click reaction. [less ▲]

Detailed reference viewed: 65 (33 ULiège)
See detailBioinspired polymers for the functionalization of stainless steel surfaces by green processes
Detrembleur, Christophe ULiege

Scientific conference (2015, September 17)

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See detailNew efficient organocatalytic system for solvent-free chemical fixation of CO2 into epoxides
Panchireddy, Satyannarayana ULiege; Gennen, Sandro ULiege; Alves, Margot ULiege et al

Poster (2015, September 11)

Due to concerns about global warming combined with the decrease of fossil resources, the chemical transformation of carbon dioxide (CO2) into added-value products has gained interest in both academic and ... [more ▼]

Due to concerns about global warming combined with the decrease of fossil resources, the chemical transformation of carbon dioxide (CO2) into added-value products has gained interest in both academic and industrial fields. To date, the chemical fixation of CO2 onto epoxides with the formation of cyclic carbonates (CC) is one of the most promising ways to valorise CO2 at an industrial scale. Indeed, CC are useful monomers for polycarbonate synthesis and they can react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPUs) by a step growth polymerization between bifunctional CC and diamines. [less ▲]

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See detailCobalt-mediated radical polymerization for the precision design of novel poly(ionic liquid) copolymers in aqueous media
Cordella, Daniela ULiege; Kermagoret, Anthony; Debuigne, Antoine ULiege et al

Poster (2015, September 11)

Poly(ionic liquid)s (PILs) have emerged as a special class of polyelectrolyte materials, featuring tunable solubility, high ionic conductivity, and a broad range of glass transition temperatures. Due to ... [more ▼]

Poly(ionic liquid)s (PILs) have emerged as a special class of polyelectrolyte materials, featuring tunable solubility, high ionic conductivity, and a broad range of glass transition temperatures. Due to their specific properties emanating from the ionic liquid (IL) units and their intrinsic polymeric nature, PILs find potential applications in various areas, such as analytical chemistry, biotechnology, gas separation, dispersants, solid ionic conductors for energy, catalysis, etc. In recent years, controlled radical polymerization (CRP) techniques have been applied to the synthesis of structurally well-defined PILs, with control attained over molar mass, dispersity, and end-group fidelity. In this poster, we will report on the implementation of cobalt-mediated radical polymerization (CMRP) technique for the precision synthesis of unprecedented PILs (co)polymers. We will discuss how an organocobalt complex can efficiently control the growth of vinyl imidazolium chains and lead to PILs with predicted molar masses and low polydispersities under mild experimental conditions, thus at low temperature and using water as a green polymerization medium. The huge potential of this system will be highlighted by describing the one-pot synthesis of all vinyl imidazolium-based block copolymers in aqueous media. This CMRP is unique for providing well-defined vinyl imidazolium based-copolymers for advanced PILs applications. [less ▲]

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