Blends of biphasic ionomers with chemically identical mono- and bifunctional oligomers

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 ▲]

Blépharochalasis d'installation rapide.

in Revue Médicale de Liège (2008), 63

Le blépharochalasis est une affection rare caractérisée par des poussées oedémateuses des paupières aboutissant à une altération de leur structure fine et principalement à un relâchement cutané. Il est le ... [more ▼]

Le blépharochalasis est une affection rare caractérisée par des poussées oedémateuses des paupières aboutissant à une altération de leur structure fine et principalement à un relâchement cutané. Il est le plus souvent bilatéral et atteint préférentiellement les paupières supérieures. Nous rapportons l’observation d’une jeune fille de 11 ans, qui présente un blépharochalasis qui s’est installé 3 mois après des épisodes successifs pratiquement subintrants d’œdème palpébral. Le diagnostic a été étoffé par un examen histologique qui a montré une absence quasi totale de fibre élastique. Le blépharochalasis survient habituellement chez le sujet jeune. Deux formes cliniques sont classiquement décrites : la forme hypertrophique et la forme atrophique, observée chez notre patiente. L’atrophie des paupières s’installe progressivement sur plusieurs années suite à des poussées œdèmateuses qui durent quelques jours et qui surviennent 3 à 4 fois par an. [less ▲]

Bleue des prés, Porc Fleuri, Poulet d'Ardenne, trois productions de qualité différenciée en Région Wallonne

(2003)

Blind source separation techniques - Another way of doing operational modal analysis

in International Operational Modal Analysis Conference, Copenhague, 2007 (2007)

In many practical applications, it is difficult or even impossible to measure the force applied to a structure. This is especially the case in civil engineering applications. Therefore, this paper ... [more ▼]

In many practical applications, it is difficult or even impossible to measure the force applied to a structure. This is especially the case in civil engineering applications. Therefore, this paper proposes to explore the utility of blind source separation (BSS) techniques for operational modal analysis. The basic idea of BSS is to recover unobserved source signals from their observed mixtures. The feasibility and practicality of the proposed method are demonstrated using an experimental application. [less ▲]

Blind tests shed light on possibilities of interpreting prehistoric stone tool prehension and hafting

in Journal of Archaeological Science (2006), 33

Blinking to threat is no sign of consciousness

Conference (2008)

Bloc péri-médullaire, anticoagulants et anti-plaquettaires: le problème est-il réglé?

Conference (2005, April 21)

Les blocages du recyclage morphologique des tissus urbains . In: Reconstruire la ville sur la ville. Recyclage des espaces dégradés

Report (2003)

Les blocages du recyclage morphologique des tissus urbains. In: Reconstruire la ville sur la ville. Recyclage des espaces dégradés

Report (2003)

Block and random copolymers of ε-caprolactone

in Polymer Degradation & Stability (1998), 59(1-3), 215-222

Conditions of the living homopolymerization of epsilon-caprolactone (CL), lactides (LA), and of the homo-oligomerization of gamma-butyrolactone (BL) are briefly described. Then block and random ... [more ▼]

Conditions of the living homopolymerization of epsilon-caprolactone (CL), lactides (LA), and of the homo-oligomerization of gamma-butyrolactone (BL) are briefly described. Then block and random copolymerizations of CL with LA are shortly reviewed. The microstructure of the resulting copolyesters in relation to some peculiarities of these processes is discussed in more detail. It is also shown that the otherwise 'non-polymerizable' BL does form high molecular weight copolymers with CL, containing up to 50 mol% repeating units derived from BL. Their molecular weight is controlled by the concentrations of the consumed comonomers and the starting concentration of the initiator. NMR and DSC data indicate the random structure of copolymers. TGA traces of the BL/CL copolymers show that the presence of the gamma-oxybutyryl repeating units randomly distributed within the poly(CL) chains improves the thermal stability of the latter. [less ▲]