References of "Jérôme, Christine"
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See detailPolymer membrane by electrospinning
Aqil, Abdelhafid ULg; Grignard, Bruno ULg; Croisier, Florence ULg et al

Poster (2008, November 28)

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See detailElectrografting of thermo-responsive polymer films on conducting surfaces
Gabriel, Sabine; Stach, M.; Confortini, O. et al

Poster (2008, November 28)

Detailed reference viewed: 27 (2 ULg)
See detailPreparation and characterization of thermoresponsive iron nanoparticles for biomedical applications
Sibret, Pierre ULg; Aqil, Abdelhafid ULg; Gohy, Jean-François et al

Poster (2008, November 28)

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See detailDesign of perfluorinated macroligand for the implementation of atom transfer radical polymerization in supercritical carbon dioxide
Grignard, Bruno ULg; Jérôme, Christine ULg; Calberg, Cédric ULg et al

Conference (2008, November 28)

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical ... [more ▼]

Due to an increasing need for polymers with well-defined architecture (diblock-, graft-, star-shaped copolymers), molecular weight and/or functional end-groups, the use of controlled radical polymerization (CRP) in scCO2 has started to gain attention. Among all the controlled processes, Atom Transfer Radical Polymerization has emerged as a robust tool for the preparation of polymers with well-defined molecular weight, architecture and chain-end functionality. The goal of the research relies on the development of ATRP of vinyl monomers in scCO2. Perfluorinated polymethacrylate, i.e. poly2,2,2-trifluoroethyl methacrylate (PFMA), was successfully prepared by homogenous ATRP using a polymeric ligand in order to complex the copper catalyst. CO2-soluble poly(2,2,2-trifluoroethylmethacrylate) was also prepared in supercritical CO2 by supported ATRP using a “pseudo-homogeneous” catalyst consisting of copper (I) ligated by macroligand immobilized onto an inorganic support, that results in polymers with well defined molecular weight and low polydispersity. The first efficient dispersion ATRP of methyl methacrylate (MMA) in scCO2 using a fluorinated polymeric ligand that had a dual role, i.e., the complexation of the copper salt and the stabilization of PMMA growing particles was also reported and the concept of dispersion ATRP was extended to the dispersion ATRP of styrene, to the synthesis of diblock copolymers beads using PMMA beads as macroinitiators, leading to (co)polymers with predictable molecular weight and narrow polydispersity. Finally, because both ATRP and alkyne-azide Huisgen’s 1,3-dipolar cycloaddition relies on the use of a Cu(I) catalyst, synthesis of pyrene end-functionalized polymers by simultaneous dispersion ATRP and click reaction was also investigated in supercritical carbon dioxide, leading to the formation of PMMA of well defined characteristics that was collected as fluorescent micropheres. [less ▲]

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See detailDispersion Atom Transfer Radical Polymerization of vinyl monomers in supercritical carbon dioxide
Grignard, Bruno ULg; Jérôme, Christine ULg; Calberg, Cédric ULg et al

in Macromolecules (2008), 41(22), 8575-8563

Controlled dispersion atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was successfully carried out in supercritical carbon dioxide in the presence of aminated fluoropolymers ... [more ▼]

Controlled dispersion atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was successfully carried out in supercritical carbon dioxide in the presence of aminated fluoropolymers. These materials played the dual role of macroligand for the copper bromide and also steric stabilizer to support formation of polymer microspheres. The livingness of the PMMA beads was confirmed by the one-pot two-step PMMA chain extension and the synthesis of poly(methyl methacrylate)-b-poly(2,2,2-trifluoroethyl methacrylate) (PMMA-b-PFMA) diblock copolymer in scCO2. Successful activator generated by electron transfer (AGET) for ATRP of MMA, using tin ethylhexanoate as a reducing agent, is also discussed, and the concept of dispersion ATRP of MMA was successfully extended to the controlled dispersion polymerization of styrene by ATRP leading to the formation of PS microparticles. Finally, due to the high solubility of the catalyst in scCO2, the purification of PMMA was investigated by supercritical fluid extraction, leading to the preparation of PMMA beads with low residual catalyst traces. [less ▲]

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See detailSynthesis of biodegradable poly-epsilon-caprolactone microspheres by dispersion ring-opening polymerization in supercritical carbon dioxide
Grignard, Bruno ULg; Stassin, Fabrice; Calberg, Cédric ULg et al

in Biomacromolecules (2008), 9(11), 3141-3149

A series of fluorinated diblock and triblock copolymers of poly(ε-caprolactone) and poly(heptadecafluorodecylacrylate) were prepared by combining ring-opening polymerization of ε-CL and atom transfer ... [more ▼]

A series of fluorinated diblock and triblock copolymers of poly(ε-caprolactone) and poly(heptadecafluorodecylacrylate) were prepared by combining ring-opening polymerization of ε-CL and atom transfer radical polymerization of the acrylate. These copolymers with well-controlled molecular weight and composition were characterized by 1H NMR spectroscopy and used as stabilizers for the dispersion ring-opening polymerization of ε-CL in supercritical carbon dioxide. The effect of composition and architecture of the polymeric stabilizers on the stabilization of PCL microspheres was investigated. Finally, purification of PCL was successfully implemented by reactive supercritical fluid extraction of the tin catalyst. [less ▲]

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See detailControlled release of drugs from multi-component biomaterials
Zalfen, Alina ULg; Nizet, D.; Jérôme, Christine ULg et al

in Acta Biomaterialia (2008), 4(6), 1788-1796

In order to control their release, drugs are encapsulated into systems which are expected to provide a certain site with a predetermined amount of drug over a well-defined period of time. Here we report ... [more ▼]

In order to control their release, drugs are encapsulated into systems which are expected to provide a certain site with a predetermined amount of drug over a well-defined period of time. Here we report on a multi-component drug delivery biomaterial that consists of a hydrogel matrix in which drug-loaded biodegradable microcarriers are dispersed, and whose potential applications could be found in the design of implantable devices with long-term activity, as required by contraceptive and hormone replacement treatments. The release profile of the drug can actually be tuned by the complex interplay of several release mechanisms, including the permeability and eventually the degradation rate of the microcarriers and the diffusion through the hydrogel. The hydrogel consisted of 2-hydroxyethyl methacrylate cross-linked by ethylene glycol dimethacrylate. The microcarriers were biodegradable poly-ε-caprolactone (PCL) microspheres in which active molecules, such as levonorgestrel (LNG), were encapsulated. The hydrogels were characterized by water swelling, thermal properties, LNG diffusion through drug-free and drug-depleted hydrogel membranes and LNG release from devices with drug dispersed in the hydrogel. The PCL microspheres were observed by scanning electron microscopy; their size distribution, LNG loading and release were also investigated. The hydrogel-microsphere assemblies were characterized in terms of the distribution of the microspheres within the hydrogel, water swelling and the release of the encapsulated molecules. The developed device, due to its composite structure, has the ability to combine several release mechanisms, leading to drug release obeying zero-order kinetics for most of the time. [less ▲]

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See detailElectrografting method for forming and regulating a strong adherent nanostructured polymer coating
Jérôme, Robert ULg; Jérôme, Christine ULg; Serwas, Harry ULg et al

Patent (2008)

Electrografting method for forming and regulating a strongly adherent nanostructured polymer coating onto an electro-conductive surface profile characterized in that the surface profile is regulated by ... [more ▼]

Electrografting method for forming and regulating a strongly adherent nanostructured polymer coating onto an electro-conductive surface profile characterized in that the surface profile is regulated by electrodeposition of nanometre- and/or micrometre-scale nuclei onto the surface profile prior to or simultaneously to the formation of the polymer coating. [less ▲]

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See detailStimuli-responsive surfaces by electrografting
Jérôme, Christine ULg

Conference (2008, October 28)

The design of stimuli-responsive coatings on a variety of solid surfaces is the topic of increasing researches. In this area, the adhesion of a stimuli-responsive polymer to the inorganic support whatever ... [more ▼]

The design of stimuli-responsive coatings on a variety of solid surfaces is the topic of increasing researches. In this area, the adhesion of a stimuli-responsive polymer to the inorganic support whatever the conditions of pH and temperature, remains a concern. In this field, we have been studying an electrochemical process able to initiate the polymerization of acrylic derivatives together with promoting their chemisorption to the substrate used as electrode. We have demonstrated the versatility of this method that can be applied to a variety of acrylics leading to the possible generation of responsive coatings to either pH or temperature. Reversible anchoring of molecules of interest has also been achieved recently by this method based on the grafting of dienes able to bind a dienophile and release it at higher temperature by retroDiels-Alder reaction. The electroinitiation has been found compatible with a variety of surfaces going from conventional metals (iron, steel, gold) to carbon (fibers and nanotubes) and semi-conductors (doped-silicon), which spreads the applications to various fields such as medical devices, biosensors, catalysis, electronics and photovoltaics. Particularly, the application of this process to AFM tips allows the straightforward functionalization of these devices allowing not only the handling of polymers at the molecular level but also the elaboration of various temperature, pH or analyte sensitive sensors at the nanometer scale. [less ▲]

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See detailPEO coated magnetic nanoparticles for biomedical application
Aqil, Abdelhafid ULg; Vasseur, S.; Duguet, E. et al

in European Polymer Journal (2008), 44(10), 3191-3199

This paper reports on the preparation, characterization and stealthiness of superparamagnetic nanoparticles (magnetite Fe3O4) with a 5 nm diameter and stabilized in water (pH 6.5) by a shell of water ... [more ▼]

This paper reports on the preparation, characterization and stealthiness of superparamagnetic nanoparticles (magnetite Fe3O4) with a 5 nm diameter and stabilized in water (pH 6.5) by a shell of water-soluble poly(ethylene oxide) (PEO) chains. Two types of diblock copolymers, i.e., poly(acrylic acid)-b-poly(ethylene oxide), PAA–PEO, and poly(acrylic acid)-b-poly(acrylate methoxy poly(ethyleneoxide)), PAA–PAMPEO, were prepared as stabilizers with different compositions and molecular weights. At pH 6.5, the negatively ionized PAA block interacts strongly with the positively-charged nanoparticles, thus playing the role of an anchoring block. Aggregates of coated nanoparticles were actually observed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The hydrodynamic diameter was in the 50–100 nm range and the aggregation number (number of nanoparticles per aggregate) was lying between several tens and hundred. Moreover, the stealthiness of these aggregates was assessed “in vitro” by the hemolytic CH50 test. No response of the complement system was observed, such that biomedical applications can be envisioned for these magnetic nanoparticles. Preliminary experiments of magnetic heating (10 kA/m; 108 kHz) were performed and specific absorption rate varied from 2 to 13 W/g(Fe). [less ▲]

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See detailNovel pH responsive-copolymers for smart drug carriers
Jérôme, Christine ULg

Conference (2008, September 22)

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See detailRecent advances in the synthesis of aliphatic polyesters by “click” chemistry
Riva, Raphaël ULg; Jérôme, Christine ULg; Jérôme, Robert ULg et al

Conference (2008, September 11)

Since the discovery of Sharpless and Meldal, the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is more and more popular in the field of macromolecular engineering owing to its robustness, its ... [more ▼]

Since the discovery of Sharpless and Meldal, the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is more and more popular in the field of macromolecular engineering owing to its robustness, its high tolerance to a wide range of functional groups without any need of protecting groups and the absence of side-products. This reaction is known to be a very efficient “click” reaction as defined by Sharpless. The chemical modification of aliphatic polyesters remains, at the time being, a very difficult task to achieve because of the very limited number of efficient chemical reactions, which can be implemented in the absence of chain degradation. The main purpose of this contribution is to report on the most recent advances on the use of CuAAC to derivatize aliphatic polyesters (Scheme 1). Interestingly enough, it was recently shown that CuAAC carried out onto aliphatic polyesters attached with either azides or alkynes is very efficient under mild conditions, which limit undesirable degradation. Several functional groups were grafted onto aliphatic polyesters by CuAAC without using any protection/deprotection reactions. The CuAAC is also very efficient to prepare aliphatic polyesters with various architectures as highlighted by the synthesis of graft copolymers, star-shaped copolymers and networks. This “click” chemistry has been combined with other polymerization mechanism such as ATRP in order to extend further the range of available polymers. [less ▲]

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See detailMacromolecular engineering of aliphatic polyesters by ring-opening polymerization
Lecomte, Philippe ULg; Jérôme, Christine ULg; Jérôme, Robert ULg

Conference (2008, September 09)

During the past few years, a steadily increasing attention was paid to the synthesis of biodegradable and biocompatible aliphatic polyesters because of potential applications as biomaterials or as ... [more ▼]

During the past few years, a steadily increasing attention was paid to the synthesis of biodegradable and biocompatible aliphatic polyesters because of potential applications as biomaterials or as environmentally friendly thermoplastics. The first purpose of this work is to show that the modification of these aliphatic polyesters by pendant functional groups is an efficient tool to tailor the main properties, including biodegradation rate, bioadhesion, hydrophilicity, degree of crystallinity. The strategies implemented for the synthesis of aliphatic polyesters bearing pendant functional groups rely on the synthesis of g-substituted e-caprolactones followed by their ring-opening polymerization and on the chemical modification of duly functionalized aliphatic polyesters.The second part of the lecture will be dedicated to some recent examples dealing with the use of functional caprolactones to prepare various architectures such as star-shaped copolymers, graft copolymers, macrocycles and networks. [less ▲]

Detailed reference viewed: 26 (8 ULg)