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Biobased thermoset resins were synthesized by functionalizing the tall oil fatty acid with hydrogen peroxide and then methacrylic anhydride. The obtained resins were characterized by FTIR to confirm the conversions. The cross-linking ability of the resins were checked by curing experiments and followed by DSC analysis regarding the extent of cross linking. TGA analysis was conducted to identify the thermal degradation patterns of cured resins. The obtained resins (blended with or without 33wt% styrene) were used as matrix and knitted viscose fibers were used as reinforcements to make bio-based composites. Ten layers of knitted viscose fibers were stacked crosswise (0/90⁰С) and hand lay-up impregnation was performed. The fiber ratio of all composites was around 63-66%. The composites were characterized by flexural testing, dynamic mechanical thermal analysis and charpy testing. This work demonstrates that manufacture of composites with both matrix and reinforcement fiber coming from renewable resources is feasible, and the resulted composites have satisfied mechanical performance. / Program: MSc in Resource Recovery - Sustainable Engineering

In recent years, bio-based polymers derived from renewable resources have become increasingly important as sustainable and eco-efficient products which can replace the products based on petrochemical-derived stocks. The objective of our work was to develop novel bio-based reactive systems suitable for high performance composite materials especially epoxy systems. The most commonly used starting monomer to formulate epoxy networks is the diglycidyl ether of bisphenol A, DGEBA, derived from bisphenol A and epichlorohydrin. Bio-based epichlorohydrin is commercially available. So the challenge to obtain a fully bio-based epoxy prepolymer is to replace bisphenol A by a bio-based precursor. Another interest for replacing bisphenol A by a bio-based precursor is that bisphenol A has been known to have estrogenic properties. In this study, we studied different bio-based epoxy systems and compared them to a classical DGEBA based system using, in a first step, isophorone diamine (IPD) as conventional curing agent. Bio-based epoxy prepolymers were derived from natural sugars, sorbitol and isosorbide respectively. Sorbitol polyglycidyl ether is available commercially, while isosorbide diglycidyl ether was synthesized either via conventional epoxidation (i.e. using epichlorohydrin) or via the diallyl isosorbide intermediate. Another bio-based epoxy prepolymer was derived from cardanol and is also a commercial product. Chemical structure of the bio-based epoxy prepolymers were analyzed by different analytical methods, gelation and crosslinking reactions were studied using rheological measurements and differential scanning calorimetry, respectively. Properties of the cured networks were evaluated using dynamic mechanical analysis and thermo gravimetric analysis. Influence of the bio-based epoxy prepolymer structure on the system properties as well as the influence of the crosslinking agent structure (either derived from renewable resources or bio-based ones) was discussed. Water absorption of the bio-based networks was also studied.

Master of Science / Department of Grain Science and Industry / Xiuzhi Susan Sun / Plant oil-based raw materials have become more attractive alternatives in polymer industry as fossil resources depletion and environmental concerns continue to arise. Camelina (camelina sativa L.) seed contains about 45% of oil and about 90% of the oil is unsaturated fatty acids such as linoleic acid, α-linolenic acid, and erucic acids. It also provides the advantages of low cost and low fertilizer demand. Functionalized oils such as epoxidized camelina oil (ECO) and di-hydroxyl camelina oil (DCO) can be used for resins, adhesives, coatings, etc. The objectives of this work were to synthesize and characterize ECO and DCO from camelina oil. The epoxidation reaction of camelina oil was completed with formic acid and hydrogen peroxide. Catalyst ratio, reaction time, and temperature effects on the epoxidation reaction were studied. The optimum epoxy content of 7.52 wt% with a conversion rate of 76.34% was obtained from camelina oil using excess hydrogen peroxide and a molar ratio of formic acid of less than 1 for 5 hours in 50 °C. Camelina oil yields higher epoxy content (7.52 wt%) than soybean oil (6.53 wt%); however, soybean oil had a higher conversion rate of 80.16% compared to camelina oil because of uniform fatty acids distribution. In this study, we found that epoxidation efficiency is significantly affected by fatty acids composition, structure, and distribution. DCO was synthesized from ECO with different reaction parameters. The ring opening of ECO was performed with water, perchloric acid, and THF as proton donor, catalyst, and solvent respectively. Hydroxyl value of DCO was measured, and the maximal hydroxyl value was 369.24 mg KOH/g. physical properties of DCO were characterized by acid value and moisture content; thermal properties of DCO were obtained using different scanning calorimeter (DSC), thermalgravimetric analysis (TGA). Amount of solvent and acid catalyst addition affected the hydroxyl value and residual acid in DCO. Heat capacity, phase transition temperatures, and thermal stability of DCO were obtained and showed higher values than ECO’s. The DCO showed higher peel adhesion when it was formulated with epoxidized soybean oils through UV curing because camelina oil allows higher epoxy content, which results in higher hydroxyl values.

The increasing demand for energy in combination with a greater awareness for our environmental impact have encouraged the development of sustainable energy sources, including materials for energy storage. Latent heat thermal energy storage by the use of phase change material (PCM) have become an area of great interest. It is a reliable and efficient way to reduce energy consumption. PCMs store and release latent heat, which means that the material can absorb the excess of heat energy, save it and release it when needed. By introducing soy wax as a biobased PCM and apply it on textile, one can achieve a thermoregulation material to be used in buildings and smart textiles. By replacing the present most used PCM, paraffin, with soy wax one cannot only decrease the use of fossil fuel, but also achieve a less flammable material. The performance of soy wax PCM applied on a textile fabric have not yet been investigated but can be a step towards a more sustainable energy consumption. The soy wax may also broaden the application for PCM due to its low flammability. The aim is to develop an environmental friendly latent heat thermal energy storage material to be used within numerous application fields.

Les résines alkydes sont les principaux liants des peintures et vernis modernes. Ces polymères sont obtenus par polycondensation de polyacides, polyols, acides gras et monoacides. L’engouement croissant pour le développement durable pousse à la transition de produits pétrosourcés vers des produits biosourcés, à coûts et performances similaires. Pour les alkydes qui utilisent déjà en partie des matières premières renouvelables (acides gras, polyols), le challenge consiste à substituer les composants pétrosourcés restants tels que les dérivés phtaliques et benzoïques. Après un état de l’art sur les alkydes, nous avons étudié les implications liées à la substitution de ces dérivés. Plusieurs résines alkydes biosourcées furent synthétisées et caractérisées par des mesures physico-chimiques (SEC, DSC, rhéomètre). Les peintures alkydes conventionnelles sèchent chimiquement par un mécanisme oxydatif qui requiert des sels de cobalt pour advenir en moins de 6 h. A cause de leur toxicité, ces sels sont sous pression par REACH. Nous avons proposé un mécanisme alternatif de réticulation non-oxydatif basé sur la réaction entre les groupes 2-oxo-1,3-dioxolane (ODO) et les amines primaires. La réaction modèle entre le carbonate de glycérol et l’éthylenediamine nous a permis de comprendre la viabilité de ce mécanisme de réticulation. La création de groupes ODO a d’abord été étudiée sur des huiles végétales afin de déterminer les conditions optimales et confirmer les possibles réactions d’oligomérisation. Des alkydes portant ces groupes ODO ont pu être synthétisées et caractérisées, puis converties en résines alkydes uréthanisées sans isocyanate par réaction avec des diamines. / Alkyd resins are the major binders used in surface coatings today. They are obtained by polycondensation of polybasic acids, polyols, fatty acids and monobasic acids. The raising sustainability awareness is pressuring for the transition from petrobased to biobased products with equivalent costs and performances. While conventional alkyd resins have high content in renewable raw materials such as fatty acids and polyols, replacement of petrobased raw materials such as phthalate and benzoic derivatives remained a challenge. After reviewing the current state-of-the-art regarding conventional alkyd resins, we focused on understanding the specific issues related to the synthesis of biobased alkyd resins. Several biobased alkyd resins were synthesized and characterized using techniques such as SEC, DSC and rheometer. Conventional alkyd paints chemically dry through an oxidative mechanism, which requires cobalt salts to occur in less than 6 h. These salts are under the scope of REACH because of their toxicity. As a possible alternative, we proposed a non-oxidative crosslinking mechanism based on the reaction of 2-oxo-1,3-dioxolane (ODO) groups and primary amines. This crosslinking mechanism was first studied with the model reaction between glycerol carbonate and ethylenediamine. The functionalization of ODO groups on vegetable oils was then studied as model molecule of alkyd resins, enabling the determination of optimal reaction conditions and that oligomerization occurs as a side reaction. Alkyd resins bearing ODO groups were then synthesized and characterized, then converted into non-isocyanate urethanized alkyd resins by reaction with diamines.

L'utilisation de matériaux isolants à base de granulats végétaux est en plein essor notamment pour la réhabilitation du bâti ancien, améliorant ainsi le confort des habitants. Ces matériaux possèdent des propriétés thermiques, hydriques et acoustiques appréciables. Cependant, leur développement est encore limité par le manque d'information sur l'évolution de leurs performances à long terme. Ainsi, l’objectif de cette étude est d’évaluer l’évolution des propriétés fonctionnelles du béton de chanvre, en identifiant les mécanismes de vieillissement lorsque le matériau est exposé à différents types d'environnements. Pour cela, deux bétons de chanvre formulés avec une même chènevotte et deux liants de nature chimique différente sont retenus. L’approche utilisée dans cette étude est pluridisciplinaire (chimique, physico-chimique, microbiologique, microstructurale, acoustique, thermique et mécanique) et multi échelle. L'étude des propriétés chimiques et microstructurales permet de comprendre les variations des propriétés fonctionnelles. Dans un premier temps, la caractérisation initiale des deux formulations a permis de mettre en évidence l’absence d’influence de la nature du liant sur les propriétés fonctionnelles des isolants, ce qui peut être en partie expliqué par des microstructures similaires. Une faible résistance mécanique des matériaux, liée à l'inhibition de la prise des liants en raison de leurs interactions avec les molécules extraites de la chènevotte, a également été mise en évidence. Dans un second temps, les bétons de chanvre ainsi que la chènevotte brute sont soumis à un vieillissement accéléré en imposant des cycles d’humidification/séchage pendant deux ans. Les modifications des performances des matériaux à différentes échéances sont comparées à celles d'échantillons de référence placés à 50% d’humidité relative et une température constante contrôlée. Dans les conditions de référence, aucune variation de propriétés n'est observée. Pour le vieillissement accéléré, les variations de propriétés mises en évidence sont induites par différents paramètres. Dans le cas de la chènevotte brute, l’action des microorganismes et l’adsorption d’eau entrainent une perte de masse et l'ouverture des porosités à l'origine des variations des propriétés acoustiques et hydriques. Pour le béton de chanvre, aucun développement fongique n’est observé en surface du matériau. En revanche, l’action de microorganismes est bien visible à l’intérieur des granulats végétaux, et des mécanismes supplémentaires sont identifiés : les réactions d'hydratation et de carbonatation au sein du liant ainsi que la minéralisation de la chènevotte entrainent des variations de propriétés thermiques, acoustiques et hydriques en modifiant la microstructure des bétons de chanvre. En conclusion, l’absence de variations des propriétés des bétons de chanvre dans les conditions de référence laisse penser que dans un bâtiment réel, leurs propriétés peuvent être stables dans le temps, les pathologies observées étant alors liées à une mise en œuvre défaillante. Pour aller plus loin, les résultats obtenus lors de ce travail devront être validés par une étude in situ qui permettrait d’estimer la durée de vie de ces matériaux / The use of insulating materials based on plant aggregates is growing quickly, especially for the rehabilitation of old buildings, thus improving the comfort of residents. These materials have significant thermal, hydric and acoustic properties. However, their development is still limited by the lack of information on the evolution of their long-term performances. Thus, the objective of this study is to evaluate the evolution of the functional properties of hemp concretes, by identifying the aging mechanisms when the material is exposed to different types of environments. For this aim, two hemp concretes formulated with one type of hemp and two binders with different chemical nature are retained. The approach of this study is multidisciplinary (chemical, physico-chemical, microbiological, microstructural, acoustic, thermal and mechanical) and multi-scale. The study of chemical and microstructural properties allows the understanding of the variations of functional properties. Firstly, the initial characterization of the both hemp concretes made it possible to demonstrate the absence of impact of the nature of the binder on the functional properties of the insulators, which can be partly explained by their similar microstructure. A weak mechanical resistance of the materials was also highlighted, related to the inhibition of the setting of the binders because of their interactions with the molecules extracted from the shiv. Secondly, hemp concretes and bulk shiv hemp are subjected to an accelerated aging by imposing cycles of humidification / drying during two years. The modifications of the material performances at different time scales are compared to reference samples stored at 50% of relative humidity and a constant controlled temperature. Under reference conditions, no variation in properties is observed. For accelerated aging, the variations of properties highlighted are induced by several parameters. In the case of bulk shiv, the action of microorganisms and the adsorption of water lead to a loss of mass and to the opening of porosities, leading to variations in acoustic properties. For hemp concretes, no fungal development is observed on the surface of the material. On the other hand, the action of microorganisms is clearly visible inside the plant aggregates, and additional mechanisms are identified: the hydration and carbonation reactions within the binder as well as the mineralization of the vegetal particles cause variations in thermal, acoustic and hydric properties by modifying the microstructure of hemp concretes.In conclusion, the absence of variations in the properties of hemp concretes in the reference conditions suggests that in a real building, their properties can be stable over time, the observed pathologies then being due to a faulty implementation. To go further, the results obtained during this work have to be validated by an in-situ study to be able to estimate the lifetime of these materials

Malgré leur grande activité antioxydante, l'utilisation de phénols naturels en tant qu'additifs antioxydants phénoliques pour les polyoléfines est limitée en raison de leur faible stabilité thermique et de leur caractère hydrophile. Nous présentons ici une synthèse chimio-enzymatique durable d’antioxydants lipophiles renouvelables spécifiquement conçus pour surmonter ces restrictions en utilisant de l’acide férulique naturel (présent dans la lignocellulose) et des huiles végétales (c.-à-d. acides lauriques, palmitiques, stéariques et glycérol). L'activité antiradicalaire (DPPH) ainsi que l'activité anti-oxydante (OIT) de ces nouveaux additifs entièrement biosourcés ont été rapportées à des antioxydants à base de carbone fossile disponibles dans le commerce tels que l'Irganox 1010® et l'Irganox 1076®. En outre, les tests d'activité œstrogénique n'ont révélé aucune perturbation du système endocrinien pour ces bisphénols nouvellement créés. La glycidylation de tous les composés a donné des précurseurs époxy biosourcés inoffensifs. Les analyses DSC, ATG et DMA démontrent que les propriétés thermomécaniques des résines époxy-amine obtenues peuvent être adaptées avec précision par le choix la longueur de la chaîne d’acides gras. / Despite their great antioxidant activities, the use of natural phenols as antioxidant additives for polyolefins is limited owing to their weak thermal stability and hydrophilic character. Herein, we report a sustainable chemo-enzymatic synthesis of renewable lipophilic phenolic antioxidants specifically designed to overcome these restrictions using naturally occurring ferulic acid (found in lignocellulose) and vegetal oils (i.e., lauric, palmitic, stearic acids, and glycerol) as starting materials. Antiradical activity (DPPH) as well as antioxidant activity (OIT) of these new fully biobased additives were reported to commercially available fossil-based antioxidants such as Irganox 1010® and Irganox 1076®. In addition, estrogenic activity tests revealed no endocrine disruption for newly created bisphenols. Glycidylation of all compounds afforded innocuous bio-based epoxy precursors. DSC, TGA and DMA analysis demonstrated that the thermo-mechanical properties of the obtained epoxy-amine resins can be finely tailored by judiciously selecting the fatty acid chain length.

La fonctionnalisation croissante des matériaux de constructions ainsi que le besoin de gestion des ressources de l'humanité rend les matériaux traditionnels à base de ciment moins performant.De nouvelles structures de paroi peuvent être envisagées en optimisant le choix de matériaux et leurs agencements. Dans ce travail nous avons choisi d'évaluer une structure pouvant remplir toutes les fonctions d'une paroi type « maison individuelle » ceci en utilisant des matériaux à faible coût et en utilisant des procédés de fabrications classiques. Les matériaux choisis proviennent majoritairement d'une source agricole renouvelable, le chanvre et son sous-produit (la chènevotte) et du recyclage des déchets de polystyrène. Nous avons établi des relations entre différentes propriétés du composites obtenu et les paramètres du procédé en particulier sur la zone des hautes teneurs en renfort et jusqu'à 100%. Nous avons également préparé la phase d'optimisation numérique d'une structure sandwich alvéolaire en modélisant le procédé et les structures ainsi obtenue. / Due to the rapidly improving functionality of building materials, and increasingly complicated human resource management issues, the traditional cement-based building materials of the past are becoming less and less desirable.These outdated materials are being replaced by new structures of wall that better optimize choices of materials and their layouts. In this study, we propose a multi-function structure to be the unit of a typical wall (individual house), which can be produced via the use of inexpensive materials and classic manufacturing processes. To achieve this, we chose the renewable agricultural source of the hemp plant (hemp yarns and hemp shive particles), along with recycled expanded polystyrene, to manufacture a fully recyclable composite. We established a relationship between the physical-mechanical properties of the resulting composite and the parameters of the manufacturing process, particularly in the zone of high load reinforcement, we successfully manufactured a composite of 100% hemp shive particles. In addition, we have also prepared the numerical optimization phase of an alveolar sandwich structure by modeling the process and the obtained structure.

As nontoxic biobased surfactants derived from plant oils and cellulose or starch, saccharide-fatty acid esters are widely used in cosmetics, food, and pharmaceutical industries due to their biocompatibility, biodegradability as well as antimicrobial activity. Generally, saccharide-fatty acid esters are synthesized chemically under high pressure, temperature and the presence of alkaline or acid catalysts leading to low-quality products (chemo-degradation of double bonds and oxygenated moieties) and large amounts of byproducts. In contrast, biocatalytic synthesis enhances sustainability: near-ambient pressure and temperature, the absence of toxic, acids and bases catalysts, and improved selectivity of products. For lipase-catalyzed synthesis under nearly anhydrous conditions, the major hurdle to be overcome is the poor miscibility of the acyl donor and acceptor substrates, resulting in slow reaction rates. Although several approaches such as, the employments of organic solvents, complexation agents, and ionic liquids, have been reported in the literature, a robust solution is desperately needed. This study focused on employing immobilized lipases under completely solvent-free conditions to synthesize saccharide-fatty acid esters using the ester products to enhance miscibility. Experimentally, metastable saccharide particles with a diameter of 10-100 micron-sized suspensions of saccharide were formed in oleic acid-rich ester mixtures initially for synthesis of saccharide-fatty acid esters in packed bed bioreactor containing immobilized lipases. Water, a by-product that limits ester yield by promoting hydrolysis, was removed via free evaporation. In this dissertation, a bioreactor system was developed for the eco-friendly solvent-free, immobilized lipase-catalyzed synthesis of biobasaed surfactants utilizing suspensions as reaction medium with 88 wt% in 6 days; the performance of the bioreactor systems developed for Objective 1 was optimized through water concentration control and interval time with 91 wt% in 4.8 days; and to improve design of bioreactor system developed in Objective 1 by in-line filter and derive a mathematical model to describe the production of esters by the bioreactor systems developed. Finally, 84 wt% ester content was achieved in 8.4 days.