Valorization of cardanol and lipidic acids and aldehydes in the field of polymer materials - PhDData

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Valorization of cardanol and lipidic acids and aldehydes in the field of polymer materials

The thesis was published by Briou, Benoît, in October 2018, Université de Montpellier.

Abstract:

One of the major challenges in the field of polymers is the substitution of oil-based molecules for the development of monomers, polymers and polymer additives. The topic of this thesis is focused on the valorization of bio-sourced molecules and particularly, cardanol and vegetable oil derivatives. Since the scope of polymers is broad, we have chosen to focus on the following three major issues.At first, we were interested in the plasticization of PVC, which is most often carried out by phthalates, a family of oil-based esters strongly suspected to be endocrine disruptors. Alternative additives were thus synthesized by simple chemical reactions from cardanol and fatty esters. Good thermal stabilities and satisfactory plasticizing properties were obtained. Finally, toxicity and ecotoxicity tests have demonstrated the absence of a disruptive impact on the secretion of sex hormones and the non-toxicity towards the environment of these bio-sourced plasticizers.In a second step, we were interested in the chemistry of phenolic resins usually prepared from phenol and formaldehyde, two molecules classified as CMR substances. Thus, a bio-sourced phenol, cardanol, and a bio-sourced aldehyde, nonanal, were reacted to reach flexible phenolic resins. This peculiar property is the result of internal plasticization of the pendant lipid chains within the polymer network. By this example, the interest of vegetable oil derivatives for the production of flexible materials was demonstrated. Finally, a compromise between the flexibility of phenolic resins and their chemical and thermal resistances was reached.Finally, we turned to the development of crosslinked polyurethanes from a fatty ester, a fatty diester and a triglyceride exhibiting alpha-hydroxyketone functions (collaboration with the CASYEN team of the ICBMS). The contribution of the alpha-ketone function on the reactivity of the related to the isocyanate reagent is only modest compared to isolated alcohol type derivatives (castor oil) and alcohol associated with another alcohol function ( triglyceride 1,2-diol). Nevertheless, the presence of intramolecular interactions from ketone groups made possible to enhance the thermal stability of the PU materials and to develop flexible crosslinked PUs by internal plasticization, as in the case of phenolic resins.This thesis brings out the advantages provided by the use of lipid phenols such as cardanol and fatty chains for the improvement of thermal stability and flexibility of polymer materials.

L’un des dĂ©fis majeurs dans le domaine des polymères est la substitution des molĂ©cules pĂ©tro-sourcĂ©es en vue de l’élaboration de monomères, polymères et d’additifs pour polymères. Le travail de cette thèse s’axe sur la valorisation de molĂ©cules bio-sourcĂ©es et plus particulièrement, du cardanol et de dĂ©rivĂ©s d’huiles vĂ©gĂ©tales. Le champ d’application des polymères Ă©tant large, nous avons choisi de nous centrer sur trois grandes problĂ©matiques.Dans un premier temps, nous nous sommes intĂ©ressĂ©s Ă  la plastification du PVC qui, actuellement, est majoritairement rĂ©alisĂ©e par des phtalates, famille d’esters pĂ©tro-sourcĂ©s vivement suspectĂ©s d’être des perturbateurs endocriniens. Des additifs de substitution ont ainsi Ă©tĂ© synthĂ©tisĂ©s par une chimie simple Ă  partir du cardanol et d’esters gras. Des stabilitĂ©s thermiques et des propriĂ©tĂ©s plastifiantes très satisfaisantes ont Ă©tĂ© obtenues. Enfin, des tests de toxicitĂ© et d’écotoxicitĂ© ont dĂ©montrĂ© l’absence d’impact perturbateur sur la sĂ©crĂ©tion d’hormones sexuelles et la non toxicitĂ© vis-Ă -vis de l’environnement de ces plastifiants bio-sourcĂ©s.Dans un second temps, nous avons revisitĂ© la chimie des rĂ©sines phĂ©noplastes habituellement prĂ©parĂ©es Ă  partir du phĂ©nol et du formaldĂ©hyde, deux molĂ©cules classĂ©es CMR. Nous avons adaptĂ© cette chimie robuste Ă  un phĂ©nol bio-sourcĂ©, le cardanol, et Ă  un aldĂ©hyde bio-sourcĂ©, le nonanal, pour obtenir des rĂ©sines phĂ©noliques souples. Cette propriĂ©tĂ© recherchĂ©e est le rĂ©sultat d’une plastification interne des chaines lipidiques pendantes au sein du rĂ©seau polymère. Par cet exemple, l’intĂ©rĂŞt des dĂ©rivĂ©s d’huiles vĂ©gĂ©tales pour l’élaboration de matĂ©riaux souples a Ă©tĂ© dĂ©montrĂ©. Un compromis entre la souplesse des rĂ©sines phĂ©noliques et leurs rĂ©sistances chimique et thermique a Ă©tĂ© atteint.Enfin, nous nous sommes tournĂ©s vers l’élaboration de polyurĂ©thanes rĂ©ticulĂ©s Ă  partir d’un ester gras, d’un diester gras et d’un triglycĂ©ride porteurs de fonctions alpha-hydroxycĂ©tone (collaboration avec l’équipe CASYEN de l’ICBMS). L’apport de la fonction alpha-cĂ©tone sur la rĂ©activitĂ© du polyol vis-Ă -vis du rĂ©actif isocyanate n’est que modeste par rapport Ă  des dĂ©rivĂ©s prĂ©sentant un groupement alcool isolĂ© sur la chaine (huile de ricin) et alcool associĂ© Ă  une autre fonction alcool (triglycĂ©ride 1,2-diol). NĂ©anmoins, la prĂ©sence d’interactions intramolĂ©culaires provenant des groupements cĂ©tone a permis d’exacerber la stabilitĂ© thermique des matĂ©riaux PU et d’élaborer des PU rĂ©ticulĂ©s souples par plastification interne comme dans le cas des rĂ©sines phĂ©noliques.Cette thèse a ainsi dĂ©montrĂ© l’apport des phĂ©nols lipidiques tels que le cardanol et des chaines grasses dans l’amĂ©lioration de la stabilitĂ© thermique et de la souplesse au sein de matĂ©riaux polymères.



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