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See detailControlled synthesis and interface properties of new amphiphilic PCL-g-PEO copolymers
Rieger, Jutta ULg; Dubois, Philippe ULg; Jérôme, Robert ULg et al

in Langmuir (2006), 22(18), 7471-7479

Novel biodegradable and biocompatible poly(epsilon-caprolactone)-graft-poly(ethylene oxide), PCL-g-PEO, copolymers consisting of biocompatible blocks have been synthesized by ring-opening copolymerization ... [more ▼]

Novel biodegradable and biocompatible poly(epsilon-caprolactone)-graft-poly(ethylene oxide), PCL-g-PEO, copolymers consisting of biocompatible blocks have been synthesized by ring-opening copolymerization of epsilon-caprolactone (epsilon CL) and a poly(ethylene oxide) (PEO) macromonomer, i.e., PEO end-capped by an epsilon-caprolactone unit (gamma PEO.CL). The control is effective on the composition and length of both the hydrophobic polyester backbone and the hydrophilic PEO grafts. The reactivity ratios have been determined by monitoring the copolymer composition in relation to the comonomer conversion. The PCL-g-PEO copolymers have a tapered (gradient) rather than a random structure consistent with r(epsilon)CL = 3.95 and r(gamma)PEO.CL = 0.05. The amphiphilic graft copolymers display surfactant properties similar to those of PEO-b-PCL diblock copolymers of comparable composition and solubility, as supported by CHCl3/water interfacial tension measured by the pendant drop method. [less ▲]

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See detailControlled Synthesis of AB2 amphiphilic triarm star-shaped block copolymers by ring-opening polymerization
Petrova, Svetla; Riva, Raphaël ULg; Jérôme, Christine ULg et al

in European Polymer Journal (2009), 45(12), 3442-3450

This paper describes the synthesis of a novel amphiphilic AB2 triarm star-shaped copolymer with A = non-toxic and biocompatible hydrophilic poly(ethylene oxide) (PEO) and B = biodegradable and hydrophobic ... [more ▼]

This paper describes the synthesis of a novel amphiphilic AB2 triarm star-shaped copolymer with A = non-toxic and biocompatible hydrophilic poly(ethylene oxide) (PEO) and B = biodegradable and hydrophobic poly(ε-caprolactone) (PCL). A series of AB2 triarm star-shaped copolymers with different molecular weights for the PCL block were successfully synthesized by a three-step procedure. α-methoxy-ω-epoxy-poly(ethylene oxide) (PEO-epoxide) was first synthesized by the nucleophilic substitution of α-methoxy-ω-hydroxy-poly(ethylene oxide) (MPEO) on epichlorohydrin. In a second step, the α-methoxy-ω,ω’-dihydroxy-poly(ethylene oxide) (PEO(OH)2) macroinitiator was prepared by the selective hydrolysis of the ω-epoxy end-group of the PEO-epoxide chain. Finally, PEO(OH)2 was used as a macroinitiator for the ring-opening polymerization (ROP) of ε-caprolactone (εCL) catalyzed by tin octoaote (Sn(Oct)2). PEO-epoxide, PEO(OH)2 and the AB2 triarm star-shaped copolymers were assessed by 1H NMR spectroscopy, size exclusion chromatography (SEC) and MALDI-TOF. The behavior of the AB2 triarm star-shaped copolymer in aqueous solution was studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). [less ▲]

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See detailControlled synthesis of an ABC miktoarm star-shaped copolymer by sequential ring-opening polymerization of ethylene oxide, benzyl beta-malolactonate, and epsilon-caprolactone
Rieger, Jutta ULg; Coulembier, Olivier; Dubois, Philippe ULg et al

in Macromolecules (2005), 38(26), 10650-10657

This paper reports on the synthesis of an amphiphilic miktoarm ABC star-shaped copolymer, s[(PEO)(PMLABz)(PCL)], consisting of biocompatible/bioresorbable arms. Indeed, PEO is a hydrophilic biocompatible ... [more ▼]

This paper reports on the synthesis of an amphiphilic miktoarm ABC star-shaped copolymer, s[(PEO)(PMLABz)(PCL)], consisting of biocompatible/bioresorbable arms. Indeed, PEO is a hydrophilic biocompatible poly(ethylene oxide) arm, PMLABz is a poly(benzyl beta-malolactonate) arm precursor of a pH-sensitive bioresorbable poly(beta-malic acid) block, and PCL is a hydrophobic bioresorbable poly(epsilon-caprolactone) arm. Each constitutive arm was prepared by ring-opening polymerization. A double-headed PEO macroinitiator [PEO-(OH)-COO-K+] was first prepared by selective hydrolysis of the alpha-lactone (2-oxepanone) end group of PEO chains end-capped by a omega-methoxy group. The anionic polymerization of benzyl beta-malolactonate (MLABz) was selectively initiated by the alpha-potassium carboxylate end group of PEO in the presence of 18-crown-6 ether. The polymerization of epsilon-caprolactone (epsilon-CL) was initiated by the hydroxyl group left at the junction of the two blocks of the as-prepared PEO-b-PMLABz diblock copolymer, in the presence of tin(II) bis(2-ethylhexanoate) (Sn(Oct)(2)). The macroinitiator, the intermediate diblock, and the final miktoarm. star-shaped copolymer were analyzed by H-1 NMR spectroscopy and size exclusion chromatography. [less ▲]

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See detailControlled synthesis of anthracene-labeled omega-amine polystyrene to be used as a probe for interfacial reaction with mutually reactive PMMA
Yin, Zhihui; Koulic, Christian; Pagnoulle, Christophe et al

in Macromolecular Chemistry and Physics (2002), 203(14), 2021-2028

Anthracene-labeled polystyrene (PS) end-capped by a primary amine has been synthesized by atom transfer radical copolymerization of styrene with 3-isopropenyl-alpha,alpha-dimethylbenzyl isocyanate (m-TMI ... [more ▼]

Anthracene-labeled polystyrene (PS) end-capped by a primary amine has been synthesized by atom transfer radical copolymerization of styrene with 3-isopropenyl-alpha,alpha-dimethylbenzyl isocyanate (m-TMI). The m-TMI co-monomer (5.7 mol-%) does not perturb the control of the radical polymerization of styrene. The pendant isocyanate groups of the copolymer chains of low polydispersity (M-w/M-n = 1.25) and controlled molecular weight (up to 35 000) have been derivatized into anthracene by a reaction with 9-methyl(aminomethyl)anthracene. The anthracene-labeled PS (ca. 2 mol-% label) has been conveniently analyzed by size-exclusion chromatography with a UV detector (SEC-UV). Moreover, the omega-bromide end-group of the copolymer chains has been derivatized into a primary amine, making the labeled PS chains reactive towards non-miscible poly(methyl methacrylate) (PMMA) chains end-capped by an anhydride. The interfacial coupling of the mutually reactive PS and PMMA chains has been studied under static conditions (i.e., at the interface between thin PS and PMMA films) and successfully analyzed by SEC-UV. [less ▲]

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See detailControlled synthesis of carboxylic acid end-capped poly(heptadecafluorodecyl acrylate) and copolymers with 2-hydroxyethyl acrylate
Grignard, Bruno ULg; Jérôme, Christine ULg; Calberg, Cédric ULg et al

in Journal of Polymer Science. Part A, Polymer Chemistry (2007), 45(8), 1499-1506

1H,1H,2H,2H-Heptadecafluorodecyl acrylate (AC8) was polymerized by reversible addition-fragmentation chain transfer and copolymerized with 2-hydroxyethyl acrylate with the formation of random and block ... [more ▼]

1H,1H,2H,2H-Heptadecafluorodecyl acrylate (AC8) was polymerized by reversible addition-fragmentation chain transfer and copolymerized with 2-hydroxyethyl acrylate with the formation of random and block copolymers, respectively. The kinetics of the (co)polymerization was monitored with H-1 NMR spectroscopy and showed that the homopolymerization and random copolymerization of AC8 were under control. As a result of this control and the use of S-1-dodecyl-S-(alpha,alpha'-dimethyl-alpha"-acetic acid)trithiocarbonate as a chain-transfer agent, the copolymer chains were end-capped by an a-carboxylic acid group. Moreover, the controlled polymerization of AC8 was confirmed by the successful synthesis of poly(1H,1H,2H,2H-heptadecafluorodecyl acrylate)-b-poly(2hydroxyethyl acrylate) diblock copolymers, which were typically amphiphilic compounds. [less ▲]

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See detailControlled synthesis of ethylene-vinyl acetate based copolymers by organometallic mediated radical polymerization
Demarteau, Jérémy ULg; Kermagoret, Anthony ULg; Jérôme, Christine ULg et al

in Matyjaszewski, Krzysztof; Sumerlin, Brent S.; Tsarevsky, Nicolay V. (Eds.) et al Controlled Radical Polymerization: Materials (2015)

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ... [more ▼]

The controlled radical copolymerization of ethylene (E) and vinyl acetate (VAc) is further investigated by organometallic- mediated radical polymerization (OMRP) using Co(acac)2 as controlling agent at ethylene pressure up to 100 bar. The effect of ethylene pressure on kinetics, level of control and copolymer composition, is discussed. Ethylene-Vinyl Acetate copolymers (EVAs) with low dispersities and ethylene content reaching 57 mol% are notably reported. This work also successfully addresses the precision design of EVA-containing block copolymers, i.e. PVAc-block-EVA. In this case, the order of the synthesis of the blocks is a key parameter. The “PVAc-first” strategy is by far more practical and efficient. [less ▲]

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See detailControlled synthesis of unsaturated aliphatic polyesters
Lou, Xudong; Detrembleur, Christophe ULg; Jérôme, Robert ULg

Poster (2003, May 16)

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See detailControlled whole body vibration to decrease fall risk and improve health related quality of life in elderly patients
Bruyère, Olivier ULg; Wuidart, M. A.; di Palma, E. et al

in Osteoporosis International (2003, November), 14(Suppl. 7), 63

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See detailControlled whole body vibration to decrease fall risk and improve health-related quality of life of nursing home residents
Bruyère, Olivier ULg; Wuidart, M. A.; Di Palma, E. et al

in Archives of Physical Medicine & Rehabilitation (2005), 86(2), 303-307

Objective: To investigate the effects of whole body vibration in the elderly. Design: Randomized controlled trial. Setting: Nursing home. Participants: Forty-two elderly volunteers. Interventions: Six ... [more ▼]

Objective: To investigate the effects of whole body vibration in the elderly. Design: Randomized controlled trial. Setting: Nursing home. Participants: Forty-two elderly volunteers. Interventions: Six-week vibration intervention plus physical therapy (PT) (n=22) or PT alone (n=20). Main Outcome Measures: We assessed gait and body balance using the Tinetti test (maximum scores of 12 for gait, 16 for body balance, 28 for global score), motor capacity using the Timed Up & Go (TUG) test, and health-related quality of life (HRQOL) using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Results: After 6 weeks, the vibration intervention group improved by a mean +/- standard deviation of 2.4 +/- 2.3 points on the gait score compared with no score change in the control group (P<.001). The intervention group improved by 3.5 +/- 2.1 points on the body balance score compared with a decrease of 03 +/- 1.2 points in the control group (P<.001). TUG test time decreased by 11.0 +/- 8.6 seconds in the treated group compared with an increase of 2.6 +/- 8.8 seconds in the control group (P<.001). The intervention group had significantly greater improvements from baseline on 8 of 9 items on the SF-36 compared with the control group. Conclusions: Controlled whole body vibration can improve elements of fall risk and HRQOL in elderly patients. [less ▲]

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See detailControlled whole body vibrations improve health related quality of life in elderly patients
Bruyère, Olivier ULg; Wuidart, Marc-Antoine; Di Palma, Elio et al

in Arthritis and Rheumatism (2003, September), 48(9, Suppl. S), 502

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See detailControlling an Agent by Focusing its Attention on Interactively Selected Patterns
JODOGNE, Sébastien ULg; Piater, Justus ULg

in HF Journal -- Belgian Journal of Electronics Communications (2005), (1), 14--16

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See detailControlling bovine leukemia virus infection: development of a specific serological test and an efficient subunit vaccine.
Portetelle, Daniel ULg; Burny, Arsène; Desmettre, Philippe et al

in Gene regulation and AIDS: Transcriptional activation, retroviruses and pathogenesis. Advances in applied biotechnology series. (1990)

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See detailControlling factors of gully erosion in the upper part of the Isser river watershed (Algiers, N. Algeria)
Daoudi, M.; Dewitte, Olivier ULg; Gérard, Paul et al

in Geophysical Research Abstracts (2007), 9

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See detailControlling flux flow dissipation by changing flux pinning in superconducting films
Grimaldi, G; Leo, A; Nigro, A et al

in Applied Physics Letters (2012), 100

We study the flux flow state in superconducting materials characterized by rather strong intrinsic pinning, such as Nb, NbN, and nanostructured Al thin films, in which we drag the superconducting ... [more ▼]

We study the flux flow state in superconducting materials characterized by rather strong intrinsic pinning, such as Nb, NbN, and nanostructured Al thin films, in which we drag the superconducting dissipative state into the normal state by current biasing. We modify the vortex pinning strength either by ion irradiation, by tuning the measuring temperature or by including artificial pinning centers. We measure critical flux flow voltages for all materials and the same effect is observed: switching to low flux flow dissipations at low fields for an intermediate pinning regime. This mechanism offers a way to additionally promote the stability of the superconducting state. [less ▲]

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See detailControlling form errors from 3D measures
Debongnie, Jean-François ULg; Masset, Luc ULg

in ASME (Ed.) Proceedings of the 1999 ASME Design Engineering Technical Conference (1999, September)

Owing to the fact that a correct evaluation of form errors is particularly difficult by the classical ways, it seems more efficient to develop numerical algorithms from 3D measures. Several methods are ... [more ▼]

Owing to the fact that a correct evaluation of form errors is particularly difficult by the classical ways, it seems more efficient to develop numerical algorithms from 3D measures. Several methods are described, including direct and iterative ones. A new method is proposed, which is based on Lp-norms and a specialized algorithm. It proved to be the most effective and robust one on every studied application. [less ▲]

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See detailControlling the effects of anomalous ARP behaviour on ethernet networks
Ármannsson, D.; Hjálmt sson, G.; Smith, Paul et al

in Proceedings of the 2005 ACM conference on Emerging network experiment and technology (2005)

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See detailControlling the electrografting of polymers onto transition metal surfaces through solvent vs monomer adsorption
Crispin, Xavier; Lazzaroni, Roberto; Geskin, Victor et al

in Journal of the American Chemical Society (1999), 121(1), 167-187

Electropolymerization of methacrylic monomers opens the possibility of chemically grafting a wide range of polymers onto transition metal surfaces. In this work, the electropolymerization of ... [more ▼]

Electropolymerization of methacrylic monomers opens the possibility of chemically grafting a wide range of polymers onto transition metal surfaces. In this work, the electropolymerization of polyacrylonitrile and polyethyl acrylate is studied in different solvents; we experimentally confirm that the choice of solvent is a critical parameter for obtaining electrografted polymers. A density-functional theory−based study modeling the interaction of solvent (acetonitrile, dimethylformamide, and pyridine) or monomer (acrylonitrile and ethyl acrylate) molecules with the Ni(100) metal surface provides the means to classify the organic molecules with respect to their ability to interact with the surface. The surface binding-energy difference between monomer and solvent is introduced in a Frumkin-type isotherm. This allows us to rationalize the experimental observations in terms of a competitive adsorption at the metal surface between the monomer and the solvent. The first step in the electrografting mechanism thus appears to be the chemisorption of the monomer at the electrode surface before cathodic polarization is applied; the chemisorbed monomer is therefore the first species reduced, giving rise to an adsorbed reactive intermediate, which is thus able to start the polymerization of a grafted chain. [less ▲]

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See detailControlling the partial coalescence of a droplet on a vertically vibrated bath
Gilet, Tristan ULg; Vandewalle, Nicolas ULg; Dorbolo, Stéphane ULg

in Physical Review E (2007), 76(3, Pt 2), 35302

A method is proposed to stop the cascade of partial coalescences of a droplet laid on a liquid bath. The strategy consists of vibrating the bath in the vertical direction in order to keep small droplets ... [more ▼]

A method is proposed to stop the cascade of partial coalescences of a droplet laid on a liquid bath. The strategy consists of vibrating the bath in the vertical direction in order to keep small droplets bouncing. Since large droplets are not able to bounce, they partially coalesce until they reach a critical size. The system behaves as a low pass filter: droplets smaller than the critical size are selected. This size has been investigated as a function of the acceleration and the frequency of the bath vibration. Results suggest that the limit size for bouncing is related to the first mode of the droplet deformation. [less ▲]

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