La transformation de la biomasse végétale en composés simples pouvant servir comme monomères pour l’élaboration de nouveaux matériaux polymères susceptibles de se substituer à leurs homologues d’origine pétrochimique a été l’un des thèmes de recherche développés au cours des deux dernières décennies. c’est dans ce vaste contexte que s’inscrivent les travaux rapportés dans ce mémoire dont l’objectif était d’élaborer une nouvelle famille d’oligoesters aliphatiques en partant de monomères biosourcés et en intégrant dans leur structure des groupes sulfonés. Cette orientation est justifié par les trois considérations suivantes (i) cela constitue une contribution à la valorisation de la biomasse végétale (ii) la présence des unités sulfonés dans leur structure leur confère des propriétés physico-chimiques particulières favorisant leur utilisation dans divers secteurs industriels. (iii) Ces oligoesters peuvent être par la suite utilisés pour la préparation des composites à base de réseaux de poly (ester-uréthane) et de liquide ionique ayant des propriétés thermomécaniques potentiellement intéressantes et une grande tendance à la dégradation hydrolytique. / The research conducted in this thesis was achieved in the context of vegetal biomass valorization. It aims to develop a new family of aliphatic oligoesters from biobased monomers and incorporating into their structure sulfonated groups. This choice is justified by the following three considerations. (i) This is a contribution to the valorization of vegetal biomass. (ii) The presence of sulfonated units in the structure of this type of polymers gives them specific physicochemical properties favoring their use in various industrial sectors. (iii) These oligoesters can be subsequently used for the preparation of poly (ester-urethane) networks and ionic liquid-based composites with potentially interesting thermomechanical properties and a great tendency towards hydrolytic degradation.

L’objectif principal a été d’élaborer de nouveaux revêtements hybrides O/I de morphologie contrôlée afin de répondre des exigences de haute stabilité thermique (300°C) et résistance à la rayure et ayant des propriétés mécaniques spécifiques. Pour répondre à ces attentes, une phase inorganique est générée in-situ par des réactions d’hydrolyse/condensation d’un précurseur inorganique silicié (TEOS) au sein de matrices organiques de microstructures variées : polyesters hyperramifiés (Boltorn H20 and H40), oligoesters ramifiés (Synthoester et dérivés tanniques). Les nombreuses fonctions hydroxyles de la composante organique et leur forme spécifique permettent, dans les conditions de synthèse choisies, de contrôler les interactions entre les phases organiques et inorganiques et retarder les mécanismes de séparation de phases induite lors de la condensation du TEOS. Les matériaux hybrides ont été analysés par TEM, SAXS, ATG et DMA, microscratch testeur. L’influence de la masse molaire, de la teneur en composés inorganiques, de la teneur en fonctions hydroxyle de la composante organique sur la morphologie finale et les propriétés thermiques et mécaniques de surface. / This study focuses on coatings based on news O/I hybrid coatings having a specific morphology to improve resistance to heat, abrasion and scratch as well as mechanical properties. To obtain and control the hybrid morphology, inorganic domains are generated in-situ via sol-gel chemistry based on hydrolysis/condensation reactions of metal alcoxydes (TEOS) into an organic polymer: hyperbranched polyesters (HBP Boltorn H20 and H40) and branched oligoesters (Synthoester, tannic acids). Which ones are high hydroxy functionalized, dense structure and peculiar shape are exploited to control the interactions between the organic and inorganic phases. The hybrid materials were characterized by TEM, SAXS, TGA, DMA, and microscratch tester. We investigated the influence of weight fraction of silica and of hydroxyl functionality of organic component on one side, and the influence of condensation degree on the other side, on the final morphology and thermal and mechanical properties.

L'objectif principal a été d'élaborer de nouveaux revêtements hybrides O/I de morphologie contrôlée afin de répondre des exigences de haute stabilité thermique (300°C) et résistance à la rayure et ayant des propriétés mécaniques spécifiques. Pour répondre à ces attentes, une phase inorganique est générée in-situ par des réactions d'hydrolyse/condensation d'un précurseur inorganique silicié (TEOS) au sein de matrices organiques de microstructures variées : polyesters hyperramifiés (Boltorn H20 and H40), oligoesters ramifiés (Synthoester et dérivés tanniques). Les nombreuses fonctions hydroxyles de la composante organique et leur forme spécifique permettent, dans les conditions de synthèse choisies, de contrôler les interactions entre les phases organiques et inorganiques et retarder les mécanismes de séparation de phases induite lors de la condensation du TEOS. Les matériaux hybrides ont été analysés par TEM, SAXS, ATG et DMA, microscratch testeur. L'influence de la masse molaire, de la teneur en composés inorganiques, de la teneur en fonctions hydroxyle de la composante organique sur la morphologie finale et les propriétés thermiques et mécaniques de surface.

Based on preliminary reports, an extended series of bolamphiphilic oligoester compounds with structural symmetry were synthesized and then tested using a planar bilayer experiment with the voltage-clamp technique. The main structures of these compounds are identical, consisting of a mono or tri-aromatic core, two octamethylene chains and two benzoyl headgroups which are all connected through ester linkages. The structural variance was provided by the four differently functionalized benzoyl headgroups. The synthetic methods of three to five steps were mainly adapted from the previously reported method.1 The methods successfully produced eight compounds with overall yields of 20 to 30%. The voltage-clamp data suggested voltage-dependent behaviors occur at low concentrations while Ohmic behaviors require at high concentrations. The activity at low potentials showed relatively erratic behavior but the channels frequently switched between opening and closing states. The activity at high potential lasted longer as the channel maintained a longer state of opening. The exponential voltage-dependent behaviors were observed at higher potential while the voltage-independent Ohmic behaviors occur at low potential. These channel behaviors are highly time-dependent as there is no control over the stability and the aggregation level for the compounds forming active channels in the membrane. In some cases the current-voltage responses appear to be asymmetrical between the positive and the negative potentials. Mechanisms consistent with the observations are proposed. / Graduate / 0485 / 0490 / yzong@uvic.ca

Based on preliminary reports, an extended series of bolamphiphilic oligoester compounds with structural symmetry were synthesized and then tested using a planar bilayer experiment with the voltage-clamp technique. The main structures of these compounds are identical, consisting of a mono or tri-aromatic core, two octamethylene chains and two benzoyl headgroups which are all connected through ester linkages. The structural variance was provided by the four differently functionalized benzoyl headgroups. The synthetic methods of three to five steps were mainly adapted from the previously reported method.1 The methods successfully produced eight compounds with overall yields of 20 to 30%. The voltage-clamp data suggested voltage-dependent behaviors occur at low concentrations while Ohmic behaviors require at high concentrations. The activity at low potentials showed relatively erratic behavior but the channels frequently switched between opening and closing states. The activity at high potential lasted longer as the channel maintained a longer state of opening. The exponential voltage-dependent behaviors were observed at higher potential while the voltage-independent Ohmic behaviors occur at low potential. These channel behaviors are highly time-dependent as there is no control over the stability and the aggregation level for the compounds forming active channels in the membrane. In some cases the current-voltage responses appear to be asymmetrical between the positive and the negative potentials. Mechanisms consistent with the observations are proposed. / Graduate / 0485 / 0490 / yzong@uvic.ca