References of "Debuigne, Antoine"
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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 ULg; Debuigne, Antoine ULg; Jérôme, Christine ULg et al

in Macromolecular Rapid Communications (in press)

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 detailPolyphosphoesters as a new platform for the design of particulate drug delivery systems
Vanslambrouck, Stéphanie; Ergul Yilmaz, Zeynep; Debuigne, Antoine ULg et al

Conference (2016, June)

Thanks to their biocompatibility and degradability properties, polyphosphates are appealing polymers for biomedical applications. In contrast to aliphatic polyesters, such as poly(ε-caprolactone) and poly ... [more ▼]

Thanks to their biocompatibility and degradability properties, polyphosphates are appealing polymers for biomedical applications. In contrast to aliphatic polyesters, such as poly(ε-caprolactone) and poly(lactide), the pentavalency of the phosphorus atom allows the easy modification of the polyphosphate properties by simply adjusting the nature, the length and the functionality of the polyphosphate pendant groups. Therefore, macromolecular engineering of polyphosphoesters was applied to design well-defined architectures and functionalities adapted to drug nanocarriers. In a first approach, amphiphilic block copolymers are synthesized by organo-catalyzed ring-opening polymerization process for the synthesis of a range of PEO-b-polyphosphate bearing various pendant groups. Post-polymerization thiol-ene click reactions preformed on PEO-b-polyphosphate copolymers was also investigated to improve the hydrophobicity of the polyphosphate. The self-assembly of these PEO-b-polyphosphate copolymers into micelles was investigated, particularly, the effect of the nature of the polyphosphate pendant groups (i) on the micelles characteristics, (ii) on the encapsulation of a poorly soluble drug and (iii) on the drug release profile. The toxicity of the different amphiphilic block copolymers was also evaluated by live/dead cell viability assays. In a second approach, double hydrophilic copolymers based on polyphosphoesters have been used as templating agent for the synthesis of calcium carbonate particles. Indeed, the use of such microparticles is becoming more and more attractive in many fields especially for biomedical applications for which fine tuning of size, morphology and crystalline form of CaCO3 particles is crucial. Although some structuring compounds, like hyaluronic acid, give satisfying results, the control of the particle structure still has to be improved. To this end, we evaluated the CaCO3 structuring capacity of the well-defined double hydrophilic block copolymers composed of poly(ethylene oxide) and of a polyphosphoester segment with affinity for calcium like poly(phosphotriester)s bearing pendant carboxylic acids or poly(phosphodiester)s with a negatively charged oxygen atom on each repeating monomer unit. [less ▲]

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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 ULg 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 detailFar beyond primary poly(vinylamine)s through free radical copolymerization and amide hydrolysis
Dréan, Mathilde ULg; Guégan, Philippe; Jérôme, Christine ULg et al

in Polymer Chemistry (2016), 7(1), 69-78

Due to their affinity for many supports, their pH responsiveness, metal binding capacity and polyelectro- lyte complexation, poly(vinylamine) derivatives have attracted attention for many applications ... [more ▼]

Due to their affinity for many supports, their pH responsiveness, metal binding capacity and polyelectro- lyte complexation, poly(vinylamine) derivatives have attracted attention for many applications including coatings, water purification, or gas membrane separation. Nevertheless, most of them possess only pendant primary amines despite the possible benefits of incorporating different amino groups along the chain. In this work, a straightforward and scalable synthesis route towards polymers bearing primary and secondary amines, as well as imidazole groups, is reported. The general strategy relies on the radical copolymerization of different vinylamides and vinyl imidazoles followed by the hydrolysis of the resulting poly(vinylamide) derivatives. Binary and ternary free radical copolymerizations of N-vinylacetamide (NVA), N-methyl vinylacetamide (NMVA) and 1-vinylimidazole (VIm) were investigated and the reactivity ratios for each copolymerization system were determined. Thanks to these values a series of statistical copolymers with predictable composition and low deviation over the chain distribution could then be synthesized. Finally, the acidic hydrolysis of the acetamide functions towards the corresponding amine was performed and optimized. Copolymers containing various pendant amino groups and with low dispersity in the chain composition could be obtained, which opens new perspectives for the above mentioned applications. [less ▲]

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See detailCore cross-linked micelles of polyphosphoester containing amphiphilic block copolymers as drug nanocarriers
Ergül, Zeynep ULg; Vanslambrouck, Stéphanie; Cajot, Sébastien et al

in RSC Advances (2016), 6(48), 42081-42088

Poly(ethylene oxide)-b-polyphosphoester amphiphilic block copolymers are known to self-assemble into polymer micelles when dissolved into water. This work aims at reporting on the improvement of the ... [more ▼]

Poly(ethylene oxide)-b-polyphosphoester amphiphilic block copolymers are known to self-assemble into polymer micelles when dissolved into water. This work aims at reporting on the improvement of the stability of the micelles at high dilution by crosslinking the hydrophobic polyphosphoester micellar core. Typically, an unsaturated alkene side-chain was introduced on the cyclic phosphate monomer according to a one-step reaction followed by its organocatalyzed polymerization initiated by a poly(ethylene oxide) macroinitiator. This strategy avoids the use of any organometallic compounds in order to facilitate the purification and meet the stringent requirements of biomedical applications. After self-assembly into water, the micelles were cross-linked by simple UV irradiation. These cross-linked micelles have then been loaded by doxorubicin to evaluate their potential as drug nanocarriers and monitor the impact of crosslinking on the release profile. [less ▲]

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See detailNovel organocobalt based on acetylacetonate ligands for the precision synthesis of telechelic polymers
Demarteau, Jérémy ULg; Cordella, Daniela ULg; 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 ▲]

Detailed reference viewed: 30 (5 ULg)
See detailSynthesis of functional polyphosphates for hydrogel and particle drug delivery systems
Vanslambrouck, Stéphanie; Ergül, Zeynep ULg; Clément, Benoit et al

Conference (2015, December 02)

Thanks to their biocompatibility and degradability properties, polyphosphates are appealing polymers for biomedical applications. In contrast to aliphatic polyesters, such as poly(ε-caprolactone) and poly ... [more ▼]

Thanks to their biocompatibility and degradability properties, polyphosphates are appealing polymers for biomedical applications. In contrast to aliphatic polyesters, such as poly(ε-caprolactone) and poly(lactide), the pentavalency of the phosphorus atom allows the easy modification of the polyphosphate properties by simply adjusting the nature, the length and the functionality of the polyphosphate pendant groups. Macromolecular engineering of polyphosphoesters was applied to design well-defined architectures and functionalities adapted to drug nanocarriers. In a first approach, amphiphilic block copolymers are synthesized by organo-catalyzed ring-opening polymerization process for the synthesis of a range of PEO-b-polyphosphate bearing various pendant groups. Post-polymerization thiol-ene click reactions preformed on PEO-b-polyphosphate copolymers was also investigated to improve the hydrophobicity of the polyphosphate. The self-assembly of these PEO-b-polyphosphate copolymers into micelles was investigated, particularly, the effect of the nature of the polyphosphate pendant groups (i) on the micelles characteristics, (ii) on the encapsulation of a poorly soluble drug and (iii) on the drug release profile. The toxicity of the different amphiphilic block copolymers was also evaluated by live/dead cell viability assays. In a second approach, double hydrophilic copolymers based on polyphosphoesters have been used as templating agent for the synthesis of calcium carbonate particles. Indeed, the use of such microparticles is becoming more and more attractive in many fields especially for biomedical applications for which fine tuning of size, morphology and crystalline form of CaCO3 particles is crucial. Although some structuring compounds, like hyaluronic acid, give satisfying results, the control of the particle structure still has to be improved. To this end, we evaluated the CaCO3 structuring capacity of the well-defined double hydrophilic block copolymers composed of poly(ethylene oxide) and of a polyphosphoester segment with affinity for calcium like poly(phosphotriester)s bearing pendant carboxylic acids or poly(phosphodiester)s with a negatively charged oxygen atom on each repeating monomer unit. [less ▲]

Detailed reference viewed: 52 (7 ULg)
See detailNew synthetic possibilities offered by organometallic-mediated radical polymerization
Debuigne, Antoine ULg; Demarteau, Jérémy ULg; 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 ULg; 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 ▲]

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See detailDouble hydrophilic polyphosphoester containing copolymers as efficient templating agents for calcium carbonate microparticles
Ergül, Zeynep ULg; Debuigne, Antoine ULg; Calvignac, Brice et al

in Journal of Materials Chemistry B (2015), 3(36), 7227-7236

The use of calcium carbonate (CaCO3) microparticles is becoming more and more attractive in many fields especially in biomedical applications in which the fine tuning of the size, morphology and ... [more ▼]

The use of calcium carbonate (CaCO3) microparticles is becoming more and more attractive in many fields especially in biomedical applications in which the fine tuning of the size, morphology and crystalline form of the CaCO3 particles is crucial. Although some structuring compounds, like hyaluronic acid, give satisfying results, the control of the particle structure still has to be improved. To this end, we evaluated the CaCO3 structuring capacity of novel well-defined double hydrophilic block copolymers composed of poly(ethylene oxide) and a polyphosphoester segment with an affinity for calcium like poly(phosphotriester)s bearing pendent carboxylic acids or poly(phosphodiester)s with a negatively charged oxygen atom on each repeating monomer unit. These copolymers were synthesized by a combination of organocatalyzed ring opening polymerization, thiol–yne click chemistry and protection/deprotection methods. The formulation of CaCO3 particles was then performed in the presence of these block copolymers (i) by the classical chemical pathway involving CaCl2 and Na2CO3 and (ii) by a process based on supercritical carbon dioxide (scCO2) technology in which CO32− ions are generated in aqueous media and react with Ca2+ ions. Porous CaCO3 microspheres composed of vaterite nanocrystals were obtained. Moreover, a clear dependence of the particle size on the structure of the templating agent was emphasized. In this work, we show that the use of the supercritical process and the substitution of hyaluronic acid for a carboxylic acid containing copolymer decreases the size of the CaCO3 particles by a factor of 6 (∼1.5 μm) while preventing their aggregation. [less ▲]

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See detailInfluence of the macromolecular surfactant features and reactivity on morphology and surface properties of emulsion-templated porous polymers
Mathieu, Kevin ULg; Jérôme, Christine ULg; Debuigne, Antoine ULg

in Macromolecules (2015), 48(18), 6489-6498

This work investigates key parameters of a straightfor- ward macromolecular surfactant-assisted functionalization strategy of porous polymers produced by high internal phase emulsion (HIPE) polymerization ... [more ▼]

This work investigates key parameters of a straightfor- ward macromolecular surfactant-assisted functionalization strategy of porous polymers produced by high internal phase emulsion (HIPE) polymerization. For that purpose, a series of well-defined amphiphilic poly(ethylene oxide)-b-poly(styrene) (PEO-b-PS) copolymers with various compositions and molar masses were synthesized by radical addition−fragmentation chain transfer (RAFT) polymerization and used as macromolecular surfactants for the emulsion-templated polymerization of styrene/divinylbenzene (S/DVB). The morphology of the resulting foams, referred to as polyHIPEs, was found dependent on the PS block length and concentration of the block copolymer surfactant in the emulsion. Moreover, we determined the lowest PS block length required for preserving the anchoring of the copolymer at the surface by physical entanglement within the S/DVB cross-linked matrix leading to a PEO-coated porous material. The functionalization of the porous monoliths with PEO was evidenced by sessile drop shape analyses and water uptake experiments. The chemical anchoring of the PEO-b-PS at the surface of polyHIPEs was also explored by interfacial initiation of the HIPE polymerization from a PEO-b-PS-RAFT macroinitiator leading to porous structures with permanent PEO coatings. In this case, copolymerizing DVB with acrylate instead of styrene improved the interconnectivity of the porous monoliths. [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 ULg; Kermagoret, Anthony; Debuigne, Antoine ULg 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 ▲]

Detailed reference viewed: 48 (5 ULg)
See detailNovel organocobalt for the synthesis of functional polymers
Demarteau, Jérémy ULg; Kermagoret, Anthony; Jérôme, Christine ULg et al

Poster (2015, September 11)

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

Organocobalt(III) with acetylacetonate (acac) ligands is the most representative example of R-Co bearing a labile C-Co bond that can release alkyl radicals under mild experimental conditions without requiring a photoactivation. The unique isolated R-Co is a short oligo(vinyl acetate) end-capped by Co(acac)2. The high lability of its C-Co bond combined to the unique capacity of Co(acac)2 to reversibly trap alkyl radicals make this R-Co unique for the precision design of unprecedented polymers by Cobalt-Mediated Radical Polymerization (CMRP). The growth of unstabilized and highly reactive growing radicals formed by the addition of R• to unconjugated vinyl monomers (vinyl esters, vinyl amides, vinyl imidazolium, vinyl chloride, etc;) 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 however placed limitations on post-functionalizations of end-chains. Other functional variants that would enable attractive chain-end derivatizations are unfortunately not available. In this poster, we will address this important challenge by describing an innovative synthetic route towards the preparation of new functional R-Co(acac)2 that are sources of halomethyl radicals under mild experimental conditions. The efficiency of these novel organocobalt complexes for the precision synthesis of end-functional and telechelic polymers will be described. Also, the solubility of these complexes in water enables the facile production of end-functionalized water soluble poly(ionic liquid)s. Further derivatizations of the halomethyl group at the chain-end of polymers produced by this system will be demonstrated by click reaction, largely broadening the range of possible functional groups. Finally, besides numerous applications in macromolecular engineering, this unexplored family of R-Co presents a high potential in radical reactions in organic synthesis by the facile production of halomethyl radicals. [less ▲]

Detailed reference viewed: 49 (5 ULg)
See detailCross-linked polymer micelles made of polyphosphate containing amphiphilic copolymers for drug delivery
Riva, Raphaël ULg; Vanslambrouck, Stéphanie ULg; Ergül, Zeynep ULg et al

Conference (2015, September 01)

In the pharmaceutical field, amphiphilic block copolymers are of great interest for the nanovectorization of active principles in Drug Delivery. Indeed, new drugs are synthesized each day but in too many ... [more ▼]

In the pharmaceutical field, amphiphilic block copolymers are of great interest for the nanovectorization of active principles in Drug Delivery. Indeed, new drugs are synthesized each day but in too many cases, their high hydrophobicity makes them useless because of the absence of an appropriated administration method. Typically, amphiphilic block copolymers present the remarkable property to self-assemble in water with formation, in most cases, of spherical micelles characterized by a hydrophobic core and a hydrophylic corona. Rapidly, their ability to encapsulate a hydrophobic drug in their hydrophiobic core was investigated to increase the solubility of the drug in aqueous media, prevent its degradation and decrease its toxicity. However, polymer micelles suffer of the main drawback to be unstable in diluted medium, leading to a premature release of the drug, when the concentration falls down the critical micellar concentration (CMC), which it is rapidly observed after intravenous injection. This work aims at reporting on the development of a drug delivery device based on a new amphiphilic block copolymers made of degradable polyphosphate and bioeliminable poly(ethylene oxide). Thanks to their biocompatibility, biodegradability and their structure similar to natural biomacromolecules, polyphosphates are appealing polymers for biomedical applications. In contrast to aliphatic polyesters, polyphosphate properties and functionality are easily tuned via the chemical nature of the lateral chains R. In order to get rid of the CMC, the crosslinking of the micelle’s core was realized by UV radiation, in order to fulfill the increasingly stringent requirements of biomedical applications. For this purpose, photo-cross-linkable groups were introduced on the polyphosphate backbone. The effect of the crosslinking rate on the drug loading and the drug release was evaluated using doxorubicin as model drug. [less ▲]

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See detailAll Poly(ionic liquid)-based block copolymers by sequential controlled radical copolymerization of vinylimidazolium monomers
Cordella, Daniela ULg; Kermagoret, Anthony; Debuigne, Antoine ULg et al

in Macromolecules (2015), 48(15), 5230-5243

The organometallic-mediated radical polymerization (OMRP) of N-vinyl-3-alkylimidazolium-type monomers, featuring the bis(trifluoromethylsulfonyl)imide counteranion (Tf2N–), in the presence of Co(acac)2 as ... [more ▼]

The organometallic-mediated radical polymerization (OMRP) of N-vinyl-3-alkylimidazolium-type monomers, featuring the bis(trifluoromethylsulfonyl)imide counteranion (Tf2N–), in the presence of Co(acac)2 as controlling agent, is reported. Polymerizations of monomers with methyl, ethyl, and butyl substituents are fast, reaching high monomer conversion in ethyl acetate as solvent at 30 °C, and afford structurally well-defined hydrophobic poly(ionic liquid)s (PILs) of N-vinyl type. Block copolymer synthesis is also achieved by sequential OMRP of N-vinyl-3-alkylimidazolium salts carrying different alkyl chains and different counteranions (Tf2N– or Br–). These block copolymerizations are carried out at 30 °C, either under homogeneous solution in methanol or in a biphasic medium consisting of a mixture of ethyl acetate and water. Unprecedented PIL-b-PIL block copolymers are thus prepared under these conditions. However, anion exchange occurs at the early stage of the growth of the second block. Finally, diblock copolymers generated in the biphasic medium can be readily coupled by addition of isoprene, forming all PIL-based and symmetrical ABA-type triblock copolymers in a one-pot process. Such a direct block copolymerization method, involving vinylimidazolium monomers bearing different alkyl chains, thus opens new opportunities in the precision synthesis of all PIL-based block copolymers of tunable properties. [less ▲]

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