References of "Bazuin, C. Géraldine"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSynthesis and thermal properties of linear amphiphilic diblock copolymers of L-lactide and 2-dimethylaminoethyl methacrylate
Kryuchkov, Maksym A.; Detrembleur, Christophe ULg; Jérôme, Robert ULg et al

in Macromolecules (2011), 44(13), 5209-5217

A well-defined series of nine poly(l-lactide)-b-(2-dimethylaminoethyl methacrylate) (PLLA-b-PDMAEMA) linear diblock copolymers with low polydispersity were prepared by ring-opening polymerization of LLA ... [more ▼]

A well-defined series of nine poly(l-lactide)-b-(2-dimethylaminoethyl methacrylate) (PLLA-b-PDMAEMA) linear diblock copolymers with low polydispersity were prepared by ring-opening polymerization of LLA using 4-isopropylbenzyl alcohol and tin octoate as the initiating system, conversion of the OH-terminated PLLA into Br-terminated macroinitiators (5, 13, and 19 kg/mol), followed by atom transfer radical polymerization of DMAEMA (to obtain one-half, equal, and twice the molecular weight of each PLLA block). Compositional analysis and molecular weight characterization were done using NMR, SEC–LS, TGA, polarimetry, and PDMAEMA quaternization/precipitation to test for residual PLLA homopolymer. DSC investigations indicate that low molecular weight amorphous PLLA or PDMAEMA blocks (less than or equal to ca. 5000 g/mol) are miscible in the second block. Compared to the parent PLLA homopolymers, PLLA crystallization in the block copolymers is significantly retarded, whereas the degree of crystallinity is only mildly affected and melting points are reduced only for the low molecular weight miscible blocks. [less ▲]

Detailed reference viewed: 31 (1 ULg)
Full Text
Peer Reviewed
See detailBlends of biphasic ionomers with chemically identical mono- and bifunctional oligomers
Plante, Michel; Bazuin, C Géraldine; Jérôme, Robert ULg

in Macromolecules (1995), 28(15), 5240-5247

Biphasic Cs and Ba carboxylated polystyrene ionomers were blended with chemically identical mono- and bifunctional oligomers whose chain lengths are significantly greater than the average segmental length ... [more ▼]

Biphasic Cs and Ba carboxylated polystyrene ionomers were blended with chemically identical mono- and bifunctional oligomers whose chain lengths are significantly greater than the average segmental length between ionic groups in the ionomer. The ionomers were chosen to have two ion contents such that, in one case, the matrix phase is dominant and, in the other, the cluster phase is dominant. From dynamic mechanical thermal analysis, it was observed that the biphasic morphology of the ionomers is preserved in all blends (containing up to 60 wt % oligomer). The monofunctional oligomers tend to have a mild plasticizing action on the two phases. In the matrix-dominated ionomer, the bifunctional oligomer has an antiplasticization effect at lower oligomer contents; this is attributed to a greater dispersion of ionic aggregates in the matrix phase, accompanied by pinning of the oligomer extremities in multiplets, which prevents plasticizing action. In the cluster-dominated ionomer, the oligomer forms a separate phase, which is related to insufficiently large ion-poor styrene regions in the ionomer to accommodate the long nonionic portion of the oligomer chains. [less ▲]

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
See detailPlasticization of biphasic ionomers by chemically identical, short, monofunctional oligomers
Plante, Michel; Bazuin, C Géraldine; Jérôme, Robert ULg

in Macromolecules (1995), 28(5), 1567-1574

Blends of carboxylated polystyrene ionomers containing 7 mol% of ionic units and carboxylate-terminated, monofunctional, monodisperse styrene oligomers of MW 800 were investigated by dynamic mechanical ... [more ▼]

Blends of carboxylated polystyrene ionomers containing 7 mol% of ionic units and carboxylate-terminated, monofunctional, monodisperse styrene oligomers of MW 800 were investigated by dynamic mechanical analysis and small angle X-ray scattering(SAXS). Both Cs and Ba carboxylate salts were studied,as well as blends of the Cs oligomer with homopolystyrene. The cluster phase is preferentially plasticized by the oligomers for both salts.; However, whereas the nonclustered phase of the Cs system is only a Little more plasticized than that of the Ba system, the cluster phase in the Cs system undergoes dramatic plasticization, the cluster transition disappearing at 5 wt % oligomer content. Simultaneously, the SAXS ''ionomer peak'' disappears. A peak reappears at 20 wt % oligomer content, suggesting the development of a new morphology, proposed to be micelles or ''inverted multiplets''. The difference between the two systems is attributed to the much stronger electrostatic interactions in the Ba system; this is analyzed in terms of elementary ion units. It is concluded that, whereas the nature of the nonpolar tail is relatively unimportant, the nature and strength of the electrostatic interactions involved can be of critical importance to the plasticization effects in blends of ionomers with short, monofunctional oligomers. [less ▲]

Detailed reference viewed: 10 (2 ULg)