De nouveaux polyuréthanes ont été synthétisés sans isocyanate et en intégrant des synthons biosourcés afin de développer des matériaux innovants et performants pour des applications dans le domaine de l’industrie automobile et du bâtiment. À l’issue d’un état de l’art, divers synthons et différentes stratégies ont été retenus afin d’obtenir de nouvelles architectures (macro)moléculaires et conférer aux matériaux finaux les propriétés physico-chimiques recherchées. Dans un premier temps, la réaction entre un biscyclocarbonate issu d’une molécule modèle, l’acide sébacique, et des diamines dimériques ainsi que plusieurs paramètres réactionnels ont été étudiés. Cette première étude a permis de montrer l’intérêt du ratio entre les monomères ainsi que l’influence de la fonctionnalité des diamines sur les propriétés chimiques, thermiques, rhéologiques et mécaniques des matériaux polyuréthanes sans isocyanate. Cette approche a permis dans un second temps de synthétiser des matériaux pouvant être entièrement biosourcés et de comparer leurs propriétés à celles des polyuréthanes conventionnels. Les performances de certains des matériaux thermodurcissables obtenus ont confirmé l’intérêt de cette stratégie pour les applications visées. Enfin, une troisième approche a été consacrée à la synthèse de polyuréthanes sans isocyanate thermoplastiques via la synthèse de prépolymères. Les différentes études ont montré l’importance de la structure des divers synthons sur l’organisation macromoléculaire, et ainsi sur les propriétés des matériaux finaux. / Novative and performant polyurethane materials without isocyanate were synthesized using biobased molecules for applications in automotive and building industries. After a state of the art, different building blocks were selected and various strategies were established to develop new (macro)molecular architectures. First, reactions between a biscyclocarbonate from a model structure and dimer diamines were studied as well as the impact of various reaction parameters. Secondly, this approach was adapted to fully biobased materials. The properties of these nonisocyanate polyurethanes were compared with those of conventional ones. The influence of the monomer structures on the final materials was also demonstrated. The performance of some thermoset materials have confirmed the importance of the chosen strategies for the desired applications. Finally, a third approach was dedicated to the synthesis of thermoplastic nonisocyanate polyurethanes via a prepolymer synthesis. The various studies have revealed the specific impact of the building block structure on the macromolecular organization, and thus on the properties of the final materials.

Consciousness about the need for a more sustainable consumption and production patterns, as well as the will to cope with issues such as social exclusion and poverty, rose in the last decades. To answer such problems, new forms of social ventures have emerged on markets, including under the legal form of corporations. Social corporations are fully-fledged limited companies that officially commit themselves to a social mission by including the latter in their bylaws. Through their commercial activities, these new forms of social ventures target a specific social outcome. Either the whole population or a targeted group can benefit from this outcome. Thus, social corporations aim to pursue the common good. Entitled “Social Ventures and the Commons”, this doctoral dissertation aims to understand how new alternative profit-seeking business models, such as social corporations, can manage and contribute to the governance of common goods. With her seminal work, Elinor Ostrom widened the path for scholars to study the commons. Ever since, the academic world has extensively relied on her eight design principles when researching commons, allowing for a varied literature on the topic and the emergence of a paradigm in recent years; however, features of this paradigm are still fuzzy as different views and concepts of commons exist. While Ostrom conducted her research on the governance of traditional commons mainly, i.e. local natural resources collectively managed, the emergence of new concepts calls for a better of their governance mechanisms. Amongst the different concepts of commons existing, new commons have recently emerged. New commons are resources that have newly been recognized as commons. They derive from the principle of “commoning”: they are shared resources collectively organized and managed and can take the form of human-made commons, like culture, knowledge or urban spaces. They can be created both by humans and/or by organizations that are managed collectively. The first chapter of the dissertation, in the form of a conceptual paper, sheds light on the capacity of new alternative profit-seeking business models to govern new commons; a topic left out by scholars so far. It states under which conditions such unconventional forms of market-oriented organizations can contribute to the governance of commons and thus become commons-governing companies. Theoretical management principles applicable in the context of commons-governing companies are proposed and guide them to implement collective action through co-management with external and/or internal stakeholders. The second chapter of the dissertation presents an original global typology of social corporations that distinguishes between three generic types according to their legal structure and underlying motivation to integrate a social mission into their bylaws. It identifies four core social corporation governance elements: voting rights implementation, profit distribution, property regime, and ownership structure. Additionally, the typology is complemented with a multiple case study of three social corporations (one per generic type). The case study focuses on the five governance capabilities that social corporations develop to be sustainable in the long run, and that relate to the three main pillars of performance, conformance, and responsibility. The third and last chapter of the thesis aims to comprehend the governance mechanisms developed by social corporations governing new commons. To do so, it draws from the community-based enterprise theory and the theory of the commons. I use qualitative data used collected within three community-based enterprises governing commons, and that adopt a social corporation legal form, in the United Kingdom. These organizations vary by date of creation, size, location, legal form, and types of new commons they contribute to. Findings show that these ventures design a triple-levelled goal governance to (1) manage the organization, (2) govern the commons, and (3) foster social good in the community. This doctoral dissertation primarily aims to contribute to the field of entrepreneurship. First, it contributes to social entrepreneurship by embracing the growing phenomenon of profit-seeking social ventures and provides with a better comprehension of their governance mechanisms, also when governing commons. Second, it sustains the development and understanding of the newly recognized entrepreneurship theory of commons. It does so by understanding how privately-held profit-seeking social ventures – social corporations – contribute to the provision of commons and become commons-governing companies. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished

La polymérisation anionique par activation du monomère permet d’accéder à une large gamme de polyéthers en utilisant un système amorçant à base d’un nucléophile associé au triisobutylaluminium. Cette voie a permis d’accéder à des chaînes polyéthers fonctionnalisées par des groupements hydroxyle à chaque extrémité. La (co)polymérisation de l’éther allylglycidique avec d’autres éthers cycliques a été réalisée puis les (co)polymères correspondants ont été post-fonctionnalisés pour introduire en particulier des fonctions cyclo-carbonate destinées à réagir avec des amines pour générer des fonctions hydroxyuréthane et ainsi préparer des matériaux type polyuréthane par une chimie sans isocyanate. Enfin des dérivés du pin, de la famille des acides résiniques, ont été modifiés chimiquement pour élaborer des matériaux de type résine époxyde et polyuréthane sans isocyanate. La polymérisation anionique par activation du monomère a également pu être réalisée sur un monomère époxydé issu de cette ressource. / Monomer-activated anionic polymerization allows the obtention of versatile polyethers using nucleophilic species in the presence of a Lewis acid, i.e. triisobutylaluminium. This method enables the synthesis of α-,ω-plurihydroxytelechelic polyethers. The (co)polymerization of allyl glycidyl ether with various epoxides allowed the preparation of copolyethers with reactive side groups. A cyclo-carbonate functionalization was carried out in order to introduce hydroxyurethane functions by reaction with amines. This reaction allows the preparation of isocyanate-free polyurethane. Finally, resinic acids were modified chemically to prepare epoxy resins and isocyanate-free polyurethanes. A polyether based on epoxidized resinic derivatives was also synthesized by ring-opening anionic polymerization and monomer activation.