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See detailPolymer/carbon based composites as electromagnetic interference (EMI) shielding materials
Thomassin, Jean-Michel ULg; Jérôme, Christine ULg; Pardoen, Thomas et al

in Materials Science & Engineering : R (2013), 74(7), 211-232

The extensive development of electronic systems and telecommunications has lead to major concerns regarding electromagnetic pollution. Motivated by environmental questions and by a wide variety of ... [more ▼]

The extensive development of electronic systems and telecommunications has lead to major concerns regarding electromagnetic pollution. Motivated by environmental questions and by a wide variety of applications, the quest for materials with high efficiency to mitigate electromagnetic interferences (EMI) pollution has become a mainstream field of research. This paper reviews the state-of-the-art research in the design and characterization of polymer/carbon based composites as EMI shielding materials. After a brief introduction, in Section 1, the electromagnetic theory will be briefly discussed in Section 2 setting the foundations of the strategies to be employed to design efficient EMI shielding materials. These materials will be classified in the next section by the type of carbon fillers, involving carbon black, carbon fiber, carbon nanotubes and graphene. The importance of the dispersion method into the polymer matrix (melt-blending, solution processing, etc.) on the final material properties will be discussed. The combination of carbon fillers with other constituents such as metallic nanoparticles or conductive polymers will be the topic of Section 4. The final section will address advanced complex architectures that are currently studied to improve the performances of EMI materials and, in some cases, to impart additional properties such as thermal management and mechanical resistance. In all these studies, we will discuss the efficiency of the composites/devices to absorb and/or reflect the EMI radiation. [less ▲]

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See detailPolymer/carbon nanotube composites for electromagnetic interference réduction
Thomassin, Jean-Michel ULg; Jérôme, Robert ULg; Detrembleur, Christophe ULg et al

in Tjong, S. C.; Mai, Y.-W. (Eds.) Physical properties and applications of polymer nanocomposites (2010)

Detailed reference viewed: 27 (8 ULg)
See detailPolymer/carbon nanotubes nanocomposites
Thomassin, Jean-Michel ULg; Caldarella, Giuseppe ULg; Germain, Albert ULg et al

Poster (2007, August 31)

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See detailPolymer/layered silicate nanocomposites by combined intercalative polymerization and melt intercalation: a masterbatch process
Lepoittevin, Bénédicte; Pantoustier, Nadège; Devalckenaere, Myriam et al

in Polymer (2003), 44(7), 2033-2040

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay ... [more ▼]

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay content PCL nanocomposites were prepared by in situ polymerization of -caprolactone intercalated between selected organo-modified silicate layers. The polymerization was catalyzed with dibutyltin dimethoxide in the presence of montmorillonites, the surface of which were previously exchanged with (functionalized) long alkyl chains ammonium cations. Then, these highly filled PCL nanocomposites were added as masterbatches in commercial PCL and PVC by melt blending. The intercalation of PCL chains within the silicate layers by in situ polymerization proved to be very efficient, leading to the formation of intercalated and/or exfoliated structures depending on the organo-clay. These masterbatches were readily dispersed into the molten PCL and PVC matrices yielding intercalated/exfoliated layered silicate nanocomposites which could not be obtained by melt blending the matrix directly with the same organo-modified clays. The formation of nanocomposites was assessed both by X-ray diffraction and transmission electronic microscopy. Interestingly, this so-called 'masterbatch' two-step process allowed for preparing PCL nanocomposites even with non-modified natural clay, i.e. sodium montmorillonite, which showed a material stiffness much higher than the corresponding microcomposites recovered by direct melt intercalation. The thermal stability of PCL nanocomposites as a function of clay content was investigated by thermogravimetry (TGA). [less ▲]

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See detailLes polymeres issus du vegetal: materiaux a proprietes specifiques pour des applications ciblees en industrie plastique.
Rabetafika, Holy-Nadia ULg; Paquot, Michel ULg; Dubois, Philippe

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2006), 10(3),

Detailed reference viewed: 79 (30 ULg)
See detailPOLYMERIC NANOVECTORS: Actual developments and perspectives
Piel, Géraldine ULg

Scientific conference (2013)

Detailed reference viewed: 29 (4 ULg)
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See detailPolymeric microparticles with immobilized peptides. Preparation and application.
Stashevskaya, K; Markvicheva, E; Grandfils, Christian ULg et al

Poster (2005, February 07)

Detailed reference viewed: 8 (0 ULg)
See detailPolymeric nanomaterials – synthesis, functionalization and applications in diagnosis and therapy
Rieger, Jutta ULg; Jérôme, Christine ULg; Jérôme, Robert ULg et al

in Kumar, Challa (Ed.) Nanomaterials for Medical Diagnosis and Therapy (2007)

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See detailPolymerisation of inverse microemulsion : application to enzyme immobilization
Lebon, F; Grandfils, Christian ULg; Jérôme, Robert ULg

Conference (2001, July 15)

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See detailPolymérisation radicalaire contrôlée par des complexes de cobalt (CMRP) : Mécanismes et ingénierie macromoléculaire.
Debuigne, Antoine ULg

Scientific conference (2010, May 12)

De nos jours, les avancées dans de nombreux domaines technologiques sont conditionnées par le développement de matériaux polymères possédant des structures et propriétés bien définies. Dans ce contexte ... [more ▼]

De nos jours, les avancées dans de nombreux domaines technologiques sont conditionnées par le développement de matériaux polymères possédant des structures et propriétés bien définies. Dans ce contexte, nous développons une méthode de polymérisation radicalaire contrôlée assistée par des complexes de cobalt(II) (CMRP) et basée sur la désactivation temporaire des chaînes radicalaires par le métal. Outre le mécanisme de la CMRP, nous aborderons son potentiel en ingénierie macromoléculaire, notamment pour la synthèse de copolymères séquencés et la fonctionnalisation des polymères en tirant profit de la réactivité spécifique des composés organométalliques qui coiffent les chaînes. Les résultats obtenus à l’aide de complexes de cobalt seront mis en perspective avec des études mettant en jeu d’autres métaux (Ti, V, Cr). [less ▲]

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See detailPolymerization in Inverse Microemulsion: An Effective Tool to Produce Biodegradable and non Biodegradable Nanoparticles
Lebon, F; Grandfils, Christian ULg; Jérôme, Robert ULg et al

in Proceedings of Material Research Society (MRS) (2002)

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See detailPolymerization method of polymer compound by in situ polymerization of monoethylenically unsaturated monomer and secondary amine
Detrembleur, Christophe ULg; Gross, Thomas; Meyer, Rolf-Volker

Patent (2004)

Provided is a method for preparing a polymer compound selected from the group consisting of an oligomer, a cooligomer, a polymer and a copolymer without using an additional free radical initiator ... [more ▼]

Provided is a method for preparing a polymer compound selected from the group consisting of an oligomer, a cooligomer, a polymer and a copolymer without using an additional free radical initiator. CONSTITUTION: The method comprises the steps of mixing at least one monoethylenically unsaturated monomer represented by HR1C=CR2R3, at least one oxidant and at least one secondary amine represented by the formula 2; and heating the mixture at a polymerization temperature of 0-220 deg.C, wherein R1, R2 and R3 are independently H, a C1-C20 alkyl group, a C1-C20 cycloalkyl group, a C6-C24 aryl group, a halogen atom, a cyano group, a C1-C20 alkyl ester group, a C1-C20 cycloalkyl ester group, a C1-C20 alkylamide group, a C1-C20 cycloalkylamide group, a C6-C24 aryl ester group or a C6-C24 arylamide group; R4 and R5 are independently a C1-C18 alkyl group, a C2-C18 alkenyl group, a C2-C18 alkynyl group, a C3-C12 cycloalkyl group, a C3-C12 hetero cycloalkyl group, a C6-C24 aryl group or a C4-C12 alkanol group; and R4 and R5 can form a C2-C13 hetero cycloalkyl residue containing O, S or N together with a nitrogen atom connecting them, or a polycyclic ring-based or polycyclic heterocycloaliphatic ring-based residue containing O, S or N, and in the each case the carbon atom of the radical next to the nitrogen atom is substituted with two or three additional organic substituents. [less ▲]

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See detailPolymerization of (L,L)-lactide and copolymerization with epsilon-caprolactone initiated by dibutyltin dimethoxide in supercritical carbon dioxide
Stassin, Fabrice; Jérôme, Robert ULg

in Journal of Polymer Science. Part A, Polymer Chemistry (2005), 43(13), 2777-2789

Ring-opening polymerization (ROP) of (L,L)-lactide (LA) has been initiated by dibutyltin dimethoxide in supercritical carbon dioxide (SC CO2). Polymerization is controlled and proceeds at quasi the same ... [more ▼]

Ring-opening polymerization (ROP) of (L,L)-lactide (LA) has been initiated by dibutyltin dimethoxide in supercritical carbon dioxide (SC CO2). Polymerization is controlled and proceeds at quasi the same rate as in toluene, which indicates that the reactivity of the propagating species is not impaired by parasitic carbonation reaction. Random copolymerization of LA with P-caprolactone (CL) has also been studied in sc CO2, and the reactivity ratios have been determined as 5.8 +/- 0.5 for LA and 0.7 +/- 0.25 for CL. These values have to be compared to 0.7 +/- 0.25 for LA and 0.15 +/- 0.05 for CL in toluene. Good control on ROP of CL and LA in SC CO2 has been confirmed by the successful synthesis of diblock copolymers by sequential polymerization of CL and LA. [less ▲]

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See detailPolymerization of epsilon-caprolactone initiated by Y alkoxide grafted onto porous silica
Martin, Eric; Dubois, Philippe ULg; Jérôme, Robert ULg

in Macromolecules (2003), 36(19), 7094-7099

Ring-opening polymerization of c-caprolactone has been initiated by Y isopropoxide grafted onto silica, in the presence of 2-propanol, in toluene at 40degreesC. The degree of polymerization is controlled ... [more ▼]

Ring-opening polymerization of c-caprolactone has been initiated by Y isopropoxide grafted onto silica, in the presence of 2-propanol, in toluene at 40degreesC. The degree of polymerization is controlled by the initial monomer/(alcohol + alkoxide) molar ratio. Deactivation of the chains by an alcohol is essential for them to be detached from the support and to be collected totally free of metal and silica residues. The alkoxide is also regenerated at the surface of the support, which allows for recycling the catalyst. [less ▲]

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See detailPolymerization of ortho-Substituted Phenylacetylenes with Well-Defined Ruthenium-Alkylidene Catalysts and Related Metathesis Initiators
Katsumata, T.; Shiotsuki, M.; Sanda, F. et al

in Macromolecular Chemistry And Physics (2009), 210(22), 1891-1902

The polymerization of (2-isopropoxyphenyl)acetylene was investigated using a wide range of well-defined ruthenium-alkylidene complexes and related olefin metathesis initiators. In view of its superior ... [more ▼]

The polymerization of (2-isopropoxyphenyl)acetylene was investigated using a wide range of well-defined ruthenium-alkylidene complexes and related olefin metathesis initiators. In view of its superior activity, the second generation Hoveyda-Grubbs catalyst was singled out for further studies. Only phenylacetylenes ortho-substituted with alkoxy, ester, fluoro, and silyl groups afforded polymers with moderate molecular weights. They were characterized by various analytical techniques, and their properties were pared with those of samples prepared using Rh and W initiators. The Ru-based polymers possessed high trans contents and took a helical conformation with predominantly one-handed screw sense when chiral side-chains were present. [less ▲]

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See detailPolymerization of β-butyrolactone initiated with Al(OiPr)3
Kurcok, Piotr; Dubois, Philippe ULg; Jérôme, Robert ULg

in Polymer International (1996), 41(4), 479-485

Polymerization of gamma-butyrolactone has been studied in toluene with Al(OiPr)3 as an initiator. The ring-opening polyaddition proceeds through a coordination-insertion mechanism at a very low rate. Well ... [more ▼]

Polymerization of gamma-butyrolactone has been studied in toluene with Al(OiPr)3 as an initiator. The ring-opening polyaddition proceeds through a coordination-insertion mechanism at a very low rate. Well defined -isopropylester, -hydroxy poly(-butyrolactone)s (PBL) are formed with a narrow molecular weight distribution at low monomer-to-initiator molar ratios, When this ratio is higher (ca. 170), a competition occurs between propagation and side reactions, i.e. elimination, inter- and intra-molecular transesterifications and thermal degradation, which is responsible for a loss of control of the PBL molecular charcteristics. The addition of a Lewis base (1 equivalent of nicotine/Al) to the Al-alkoxide initiator has no significant effect on the polymerization rate, although the chain microstructure is deeply affected since predominantly syndiotactic PBL chains are formed (63% syndio-diads) in contrast to a completely atactic polymer in the absence of nicotine. [less ▲]

Detailed reference viewed: 79 (2 ULg)