References of "Debuigne, Antoine"
     in
Bookmark and Share    
See detailKey role of metal-coordination in cobalt mediated radical polymerization
Debuigne, Antoine ULg; Poli, Rinaldo; Jérôme, Christine ULg et al

Poster (2008, May 22)

Detailed reference viewed: 7 (1 ULg)
Full Text
Peer Reviewed
See detailSynthesis of novel well-defined poly(vinyl acetate)-b-poly(acrylonitrile) and derivatized water-soluble poly(vinyl alcohol)-b-poly(acrylic acid) block copolymers by cobalt-mediated radical polymerization
Debuigne, Antoine ULg; Warnant, Jérôme; Jérôme, Robert ULg et al

in Macromolecules (2008), 41(7), 2353-2360

Poly(vinyl acetate)−Co(acac)2 macroinitiators, prepared by cobalt-mediated radical polymerization of vinyl acetate (VAc), were used to synthesize well-defined poly(vinyl acetate)-b-poly(acrylonitrile ... [more ▼]

Poly(vinyl acetate)−Co(acac)2 macroinitiators, prepared by cobalt-mediated radical polymerization of vinyl acetate (VAc), were used to synthesize well-defined poly(vinyl acetate)-b-poly(acrylonitrile) (PVAc-b-PAN) block copolymers. Different solvents and temperatures were tested for the polymerization of the acrylonitrile segment by cobalt-mediated radical polymerization (CMRP), and copolymers with low polydispersity were obtained provided that dimethylformamide was used as solvent at 0 °C. The mechanism of control was assumed to change from a degenerative chain transfer mechanism for the VAc polymerization to a reversible-termination process for the AN polymerization. The hydrolysis of the ester groups of the PVAc block and the nitrile groups of the PAN sequence of the copolymer by potassium hydroxide in an ethanol/water mixture provided the double hydrophilic and pH-responsive poly(vinyl alcohol)-b-poly(acrylic acid) block copolymer. Finally, the pH responsiveness of these copolymers was demonstrated by DLS pH titration with formation of aggregates at pH < 3. [less ▲]

Detailed reference viewed: 38 (7 ULg)
Full Text
Peer Reviewed
See detailMechanistic Insights into the Cobalt-Mediated Radical Polymerization (CMRP) of Vinyl Acetate with Cobalt(Iii) Adducts as Initiators
Debuigne, Antoine ULg; Champouret, Yohan; Jérôme, Robert ULg et al

in Chemistry : A European Journal (2008), 14(13), 4046-4059

Over the past few years, cobalt-mediated radical polymerization (CMRP) has proved efficient in controlling the radical polymerization of very reactive monomers, such as vinyl acetate (VAc). However, the ... [more ▼]

Over the past few years, cobalt-mediated radical polymerization (CMRP) has proved efficient in controlling the radical polymerization of very reactive monomers, such as vinyl acetate (VAc). However, the reason for this success and the intimate mechanism remained basically speculative. Herein, two mechanisms are shown to coexist: the reversible termination of the growing poly(vinyl acetate) chains by the Co(acac)(2) complex (acac: acetylacetonato), and a degenerative chain-transfer process. The importance of one contribution over the other strongly depends on the polymerization conditions, including complexation of cobalt by ligands, such as water and pyridine. This significant progress in the CMRP mechanism relies on the isolation and characterization of the very first cobalt adducts formed in the polymerization medium and their use as CMRP initiators. The structure proposed for these adducts was supported by DFT calculations. Beyond the control of the VAc polymerization, which is the best ever achieved by CMRP, extension to other monomers and substantial progress in macromolecular engineering are now realistic forecasts. [less ▲]

Detailed reference viewed: 32 (17 ULg)
Full Text
See detailMetal-coordination: an effective lever for cobalt-mediated radical polymerization
Debuigne, Antoine ULg; Jérôme, Christine ULg; Jérôme, Robert ULg et al

in Polymer Preprints (2008), 49(27), 193-194

Detailed reference viewed: 11 (3 ULg)
Full Text
Peer Reviewed
See detailAmphiphilic poly(vinyl acetate)-b-poly(N-vinylpyrrolidone) and novel double hydrophilic poly(vinyl alcohol)-b-poly(N-vinylpyrrolidone) block copolymers prepared by cobalt-mediated radical polymerization
Debuigne, Antoine ULg; Willet, Nicolas ULg; Jérôme, Robert ULg et al

in Macromolecules (2007), 40(20), 7111-7118

Well-defined amphiphilic block copolymers of poly(vinyl acetate) (PVAc) and poly(N-vinylpyrrolidone) (PNVP) were synthesized by cobalt-mediated radical polymerization (CMRP). The NVP polymerization ... [more ▼]

Well-defined amphiphilic block copolymers of poly(vinyl acetate) (PVAc) and poly(N-vinylpyrrolidone) (PNVP) were synthesized by cobalt-mediated radical polymerization (CMRP). The NVP polymerization initiated by poly(vinyl acetate) end-capped by the cobalt(II)acetylacetonate complex met the criteria of controlled polymerization, i.e., first-order kinetic in NVP, increase of the molar mass with the NVP conversion, and narrow molar mass distribution. Therefore, the length of the two blocks can be tuned by the [VAc]/[Co(acac)(2)] and the [NVP]/[PVAc] ratios for the synthesis of the macroinitiator and the polymerization of the second monomer, respectively. These amphiphilic PVAc-b-PNVP block copolymers were easily converted into the double hydrophilic PVOH-b-PNVP counterparts by selective methanolysis of the PVAc block. These two types of copolymers were prone to self-association into micelles in appropriate solvents. [less ▲]

Detailed reference viewed: 41 (5 ULg)
See detailCobalt(II) complexes as controlling agents for the radical polymerization of vinyl monomers
Debuigne, Antoine ULg; Sciannaméa, Valérie; Piette, Yasmine ULg et al

Poster (2007, August 31)

Detailed reference viewed: 14 (3 ULg)
Full Text
Peer Reviewed
See detailSynthesis and evaluation of sterically hindered 1,1-diamantyl nitroxide as a low-temperature mediator for the stable free radical polymerization process
Debuigne, Antoine ULg; Chan-Seng, Delphine; Li, Lichun et al

in Macromolecules (2007), 40(17), 6224-6232

An efficient procedure for the oxidation of 1,1-diadamantylamine with m-chloroperbenzoic acid (m-CPBA) to the corresponding sterically hindered nitroxide in high yield (72%) is reported. The corresponding ... [more ▼]

An efficient procedure for the oxidation of 1,1-diadamantylamine with m-chloroperbenzoic acid (m-CPBA) to the corresponding sterically hindered nitroxide in high yield (72%) is reported. The corresponding styrene-based alkoxyamine was synthesized by an atom transfer radical addition (ATRA) reaction. Because of the bulkiness of the adamantyl substituents, the cleavage of the C−ON bond of the alkoxyamine occurred readily at temperatures below 100 °C. However, in spite of the low bond dissociation temperature of the alkoxyamine, the (co)polymerizations of styrene and n-butyl acrylate proceeded poorly. The results in this paper support the argument that the most important determinant in a nitroxide-mediated polymerization of styrene and acrylate is the ability to control the excess concentration of nitroxide in solution either by an inherent instability of the nitroxide or by the use of additives that destroy the excess nitroxide. Thus, for the 1,1-diadamantyl nitroxide case, and maybe more generally, while a lower C−O bond dissociation energy of an alkoxyamine moiety at the end of the chain may allow lower polymerization temperatures and faster reactions rates, it does not enable polymerizations to proceed to high conversions if the excess nitroxide is not controlled in some manner. [less ▲]

Detailed reference viewed: 14 (2 ULg)
See detailAdvances in cobalt mediated radical polymerization (CMRP) of vinyl monomers
Debuigne, Antoine ULg; Detrembleur, Christophe ULg; Bryaskova, Rayna et al

Conference (2007, July 11)

Detailed reference viewed: 20 (3 ULg)
Full Text
Peer Reviewed
See detailSynthesis of poly(vinyl acetate)-b-polystyrene and poly(vinyl alcohol)-b-polystyrene copolymers by cobalt-mediated radical polymerization
Bryaskova, Rayna ULg; Willet, Nicolas ULg; Debuigne, Antoine ULg et al

in Journal of Polymer Science. Part A, Polymer Chemistry (2007), 45(1), 81-89

Well-defined poly(vinyl acetate) macroinitiators, with the chains thus end-capped by a cobalt complex, were synthesized by cobalt-mediated radical polymerization and used to initiate styrene ... [more ▼]

Well-defined poly(vinyl acetate) macroinitiators, with the chains thus end-capped by a cobalt complex, were synthesized by cobalt-mediated radical polymerization and used to initiate styrene polymerization at 30 degrees C. Although the polymerization of the second block was not controlled, poly(vinyl acetate)-b-polystyrene copolymers were successfully prepared and converted into amphiphilic poly(vinyl alcohol)-b-polystyrene copolymers by the methanolysis of the ester functions of the poly(vinyl acetate) block. These poly(vinyl alcohol)-b-polystyrene copolymers self-associated in water with the formation of nanocups, at least when the poly(vinyl alcohol) content was low enough. [less ▲]

Detailed reference viewed: 55 (8 ULg)
Full Text
Peer Reviewed
See detailStable free radical polymerization of n-butyl acrylate in the presence of high temperature initiators
Chan-Seng, Delphine; Debuigne, Antoine ULg; Georges, Michaël K.

in European Polymer Journal (2007), 45(1), 211-216

Living radical polymerizations of acrylate are known to be difficult to achieve using TEMPO as a mediator. The stable free radical polymerization (SFRP) of acrylate tends to stop at low monomer conversion ... [more ▼]

Living radical polymerizations of acrylate are known to be difficult to achieve using TEMPO as a mediator. The stable free radical polymerization (SFRP) of acrylate tends to stop at low monomer conversion due to the accumulation of TEMPO in the medium as a result of unavoidable bimolecular termination. Rather than solving this problem by destroying the excess nitroxide using ascorbic acid or glyceraldehyde associated with pyridine as reported recently, high temperature initiators were used to slowly and continuously generate new radicals throughout the polymerization to consume the excess TEMPO molecules. Polymerizations of n-butyl acrylate initiated by the alkoxyamine unimer (1-benzoyloxy)-2-phenyl-2-(2′,2′,6′,6′-tetramethyl-1′-piperidinyloxy)ethane (BST) were performed between 130 °C and 134 °C in the presence of a series of high temperature peroxide and azo initiators. The best results in this study were obtained by the continuous addition of small amounts of di-tert-amyl peroxide throughout the polymerization. Under these conditions, the acrylate polymerizations fulfilled the criteria of a controlled polymerization process although the molecular weight distributions were slightly broad (Mw/Mn 1.5). [less ▲]

Detailed reference viewed: 83 (2 ULg)
Full Text
Peer Reviewed
See detailCobalt-mediated radical polymerization (CMRP) of vinyl acetate initiated by redox systems: Toward the scale-up of CMRP
Bryaskova, Rayna ULg; Detrembleur, Christophe ULg; Debuigne, Antoine ULg et al

in Macromolecules (2006), 39(24), 8263-8268

A redox initiating system was developed in order to bypass 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (V70) as the initiator of the cobalt-mediated radical polymerization (CMRP) of vinyl acetate ... [more ▼]

A redox initiating system was developed in order to bypass 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (V70) as the initiator of the cobalt-mediated radical polymerization (CMRP) of vinyl acetate (VAc) in the presence of cobalt(II) acetylacetonate (Co(acac)(2)). It is indeed a problem to stock up with V70 because of needed storage at -20 degrees C during transportation. This paper reports on the controlled CMRP of VAc initiated by ascorbic acid combined with either lauroyl peroxide or benzoyl peroxide at 30 degrees C. Substitution of citric acid for ascorbic acid results in faster polymerization whereas the polymerization control is maintained. All these improvements facilitate the implementation of the vinyl acetate CMRP and open the door to the scale-up of the process. [less ▲]

Detailed reference viewed: 27 (5 ULg)
Full Text
Peer Reviewed
See detailSupported cobalt mediated radical polymerization (SCMRP) of vinyl acetate and recycling of the cobalt complex
Sciannamea, Valérie; Debuigne, Antoine ULg; Piette, Yasmine ULg et al

in Chemical Communications (2006), (40), 4180-4182

Cobalt complexes supported on silica and Merrifield resin are effective mediators for the controlled radical polymerization of vinyl acetate.

Detailed reference viewed: 20 (3 ULg)