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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Procédé de synthèse, propriétés et applications d'élastomères techniques à base d‘itaconates / Synthesis, properties and applications of itaconate based engineering elastomers

Zhou, Xinxin 07 February 2018 (has links)
Cette thèse traite la préparation et l'application d’élastomères bio-sourcés et leurs nanocomposites qui sont les suivants : (1) des nanocomposites basés sur le 3,9 - bis [ethyl-2-à 1,1 terne {b-(3-tertbutyle-4-hydroxy-5-méthylephényle) propionyloxy} éthyle]-2,4,8,10-tetraoxaspiro-[5,5]-undécane (AO-80) et le poly(itaconate de diisoamyle-co-isoprène) (PDII), (2) le poly(itaconate de dibutyle-co-isoprène-co-acide méthacrylique) (PDIM), un élastomère carboxylique bio-sourcé, et des nanocomposites basés sur cet élastomère et la silice ou les nanotubes de halloysite, (3) le poly(itaconate de dibutyle-co-butadiène) (PDIB), un nouvel élastomère bio-sourcé, et des nanocomposites basés sur cet élastomère et la silice. Des pneus verts bio ont été fabriqués en utilisant les nanocomposites PDIB/silice dans une formulation de bande de roulement de pneu. En plus de la préparation de ces dits élastomères bio et leurs nanocomposites, cette thèse donne aussi une revue sur les travaux sur des liaisons sacrificielles bio-inspirées qui sont introduites dans des matériaux polymères. Cette revue servira d'un guide pour incorporer des liaisons sacrificielles dans des élastomères à base d’itaconate ayant une grande rigidité et résistance / This thesis deals with the preparation and application of itaconate based engineering elastomers and their nanocomposites. The following elastomers or nanocomposites were prepared: (1) nanocomposites based on 3,9-bis[1,1-dim ethyl-2-{b-(3-tertbutyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro-[5,5]-undecane (AO-80) and poly(diisoamyl itaconate-co-isoprene) (PDII), (2) a bio-based carboxylic elastomer, poly(dibutyl itaconate-co-isoprene-co-methacrylic acid) (PDIM), and nanocomposites based on it and silica or halloysite nanotubes, (3) a novel bio-based elastomer, poly(dibutyl itaconate-co-butadiene) (PDIB), and nanocomposites based on it and silica. Bio-based green tires were manufactured by using PDIB/silica nanocomposite in a tire tread formulation. In addition to the preparation of the above bio-based elastomers and their nanocomposites, this thesis also gives a review on the progresses on bio-inspired sacrificial bonds in polymeric materials. This review will serve as a guide to engineer sacrificial bonds into itaconate based elastomers with high strength and toughness
2

Tough bio-based elastomer nanocomposites with high performance for engineering applications

Wei, T., Lei, L., Kang, H., Qiao, B., Wang, Z., Zhang, L., Coates, Philip D., Hua, K-C., Kulig, J. January 2012 (has links)
Biomass feedstock is a viable alternative to finite fossil fuel resources to provide many of the same—plus others that petrochemicals cannot—chemical building blocks required to fabricate durable and high-performance materials. We demonstrate here for the first time a new generation of synthesized elastomers, namely bio-based engineering elastomers (BEE). These are of particular significance because they are synthesized from monomers derived from biomass, by routes which are suitable for large scale production, and they exhibit thermo-mechanical properties at least equivalent to current commercial petrochemical-derived elastomers. Bio-based monomers in large scale production, such as sebacic acid, itaconic acid, succinate acid, 1,3-propanediol, and 1,4 butanediol are chosen to generate the first synthetic BEE matrix through melting polycondensation—a comparatively simple reaction scheme offering good control and the potential for low cost, large-scale production. A novel linear BEE, an almost non-crystalline copolyester elastomer with low glass transition temperature (Tg) containing double bonds is designed and synthesized using multiple monomers (to help suppress crystallization). Silica nanoparticles are then introduced into the BEE matrix to achieve significant strengthening and improved environmental stability. Chemical crosslinks formed by peroxide and the pendant double bonds in the copolyester macromolecules endow the BEE with both the necessary high elasticity and required environmental stability. The BEE nanocomposites obtained exhibit excellent thermomechanical properties, such as an ultimate tensile strength of 20 MPa.

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