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Biobased Thermosets from Vegetable Oils. Synthesis, Characterization, and PropertiesGerard Lligadas PuigEl desenvolupament sostenible va esdevenir com una de les idees claus del segle 20. S'entén per desenvolupament sostenible aquell tipus de desenvolupament que és capaç de satisfer les necessitats actuals sense comprometre els recursos i possibilitats de les futures generacions. Per assolir un desenvolupament sostenible és necessari promoure un desenvolupament social i econòmic pendent en tot moment del medi ambient. La conservació i la gestió dels residus és especialment important en aquest procés. La creixent demanda de productes derivats del petroli, juntament amb la disminució progressiva de les reserves de petroli són algunes de les moltes raons que han encoratjat la industria química a començar a utilitzar les fonts renovables com a matèria prima.En aquest context, en els darrers anys l'atenció s'ha centrat en la utilització de recursos anualment renovables, com són els recursos agrícoles, en la producció d'una gran varietat de productes industrials. Un dels recursos renovables més interessants per a la indústria química són els olis vegetals degut a la seva elevada disponibilitat i el seu ampli ventall d'aplicacions. Els olis vegetals formen part de la família de compostos químics coneguts com lípids, i estan constituïts majoritàriament per molècules de triglicèrids. Els triglicèrids estan formats per tres molècules d'àcid gras unides a una molècula de glicerol mitjançant enllaços ester. Els àcids grassos que es troben en la majoria d'olis vegetals estan constituïts per cadenes alifàtiques insaturades de entre 14 i 22 àtoms de carboni.La explotació industrial dels recursos naturals està actualment en el punt de mira de la comunitat científica. Concretament, el desenvolupament de materials polimèrics derivats de fonts renovables està rebent un interès creixent degut a la incertesa en el preu i les reserves de petroli. La substitució del petroli per productes derivats de fonts renovables és consistent amb el concepte de desenvolupament sostenible. El propòsit del treball portat a terme en aquesta tesi doctoral va ser desenvolupar nous materials termoestables utilitzant olis vegetals com a productes de partida. En el capítol 1 es discuteix la contribució de la química en el desenvolupament sostenible i es descriuen les possibilitats dels olis vegetals com a productes de partida en la síntesi de materials polimèrics. El capítol 2 descriu la preparació de dos noves famílies de materials híbrids orgànics-inorgànics derivats d'olis vegetals. Es descriu síntesi i caracterització de polímers híbrids derivats d'àcids grassos que contenen dobles enllaços carboni-carboni terminals utilitzant la reacció d'hidrosililació com a reacció d'entrecreuament, i la preparació de polímers derivats d'oli de llinosa epoxidat nanoreforçats amb silsesquioxans polièdrics. En el capítol 3 es descriu la síntesi d'un nou compost fosforat derivat de fonts renovables. Aquest compost s'ha utilitzat com a compost retardant a la flama reactiu en la preparació de resines epoxi derivades de fonts renovables amb propietats de resistència a la flama. La incorporació de fòsfor en resines epoxi d'aquest tipus ha donat lloc a polímers amb bones propietats de resistència a la flama. Finalment, en el capítol 4 es descriu la preparació d'una nova família de polièter poliols derivats d'oleat de metil epoxidat com a font renovable. Aquests poliols s'han utilitzat en la síntesi de poliuretans amb aplicacions específiques: poliuretans que incorporen silici amb propietats de resistència a la flama, i poliuretans segmentats amb aplicacions en biomedicina.Biobased Thermosets from Vegetable Oils. Synthesis, Characterization, and PropertiesGerard Lligadas PuigSustainable development, which became a key idea during the 20th century, may be regarded as the progressive and balanced achievement of sustained economic development, and improved social equity and environmental quality. Sustainable development comprises the three components of society, environment, and economy, and its goals can only be achieved if all three components can be satisfied simultaneously.The conservation and management of resources is especially important to this process. The growing demand for petroleum-based products and the resulting negative impact on the environment, plus the scarcity of non-renewable resources, are some of the many factors that have encouraged the chemical industry to begin using renewable resources as raw materials.This situation has led to considerable attention being focused recently on the use of annually renewable agricultural feedstock to produce a wide range of base chemicals and other industrial products. The renewable raw materials that are most important to the chemical industry are natural oils and fats because of their high availability and versatile applications. Vegetable oils constitute about 80% of the global oil and fat production, with 20% (and declining) being of animal origin. The use of these materials offers an alternative approach that is both sustainable and, with the right application, far more environmentally benign than fossil sources.Vegetable oils and fats form part of a large family of chemical compounds known as lipids. Vegetable oils are predominantly made up of triglyceride molecules, which have the three-armed star structure. Triglycerides comprise of three fatty acids joined at a glycerol junction. Most of the common oils contain fatty acids that vary from 14 to 22 carbons in length, with 0 to 3 double bonds per fatty acid.Research into the industrial exploitation of products derived from renewable resources is currently of immense international importance. In particular, the development of polymer materials from renewable resources is receiving considerable attention since the availability of crude oil will become severely restricted within the foreseeable future. The replacement of crude oil by renewable raw materials is also consistent with the aim of global sustainability.The purpose of the study reported in this thesis was to develop new biobased thermosetting polymers from vegetable oils as renewable resources. To achieve this goal, the experimental work focused on exploiting the reactivity of unsaturated fatty compounds. Chapter 1 discusses the contribution of chemistry to sustainable development, and also presents an overview of recent developments in the chemistry of vegetable oil-based polymers. Chapter 2 describes the preparation of two new types of organic-inorganic hybrid materials from vegetable oils. Hybrids with promising properties for optical applications were prepared by the hydrosilylation of alkenyl-terminated fatty acid derivatives with several hydrosilylating agents, and the first example of the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from vegetable oil derivatives is reported. Chapter 3 describes the synthesis of a new phosphorus-containing fatty acid derivative. This compound is used as a reactive flame-retardant in the preparation of flame-retardant epoxy resins from terminal epoxy fatty acid derivatives. The incorporation of phosphorous into biobased epoxy resins yields polymers with good flame-retardant properties. Finally, chapter 4 describes the preparation of a new family of epoxidized methyl oleate based polyether polyols. These polyols are used in the synthesis of polyurethanes, some with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties, and polyurethane networks with potential applications in biomedicine.

The oil and gas well completion method of hydraulic fracturing faces several environmental challenges: the process is highly water-intensive; it generates a significant volume of wastewater; and it is associated with widespread flaring of co-produced natural gas. One possible solution to simultaneously mitigate these challenges is to use the energy from flared natural gas to power on-site wastewater treatment, thereby reducing 1) flared gas without application, 2) the volumes of wastewater, and 3) the volumes of freshwater that need to be procured for subsequent shale production, as the treated wastewater could be reused. In regions with minimal flaring a potential solution is to couple renewable electricity (generated from solar and wind energy) with on-site wastewater treatment, thereby 1) reducing the volumes of wastewater, 2) reducing the volumes of freshwater that need to be procured for subsequent shale production, and 3) displacing fossil fuel energy for treatment. This study builds an analytical framework for assessing the technical potential of these approaches. In this research, the hydraulic fracturing wastewater characteristics (such as quality, quantity, and flow rates) were considered along with various treatment technologies best suited to utilizing natural gas and renewable electricity, using the Permian Basin in west Texas as a geographic test bed for analysis. For the analysis looking at using flared natural gas energy for on-site treatment, the required volume of gas to meet the thermal energy requirements for treatment was calculated on a per-well basis. Additionally, the volume of product water (defined here as the treated water that can be reused) based on the technology type was determined. Finally, the theoretical maximum volume of product water that could be generated using the total volume of natural gas that was flared in Texas in 2012 as a benchmark was calculated. It was concluded that the thermal energy required to treat wastewater that returns to the surface over the first ten days after a well is completed is 140–820 Million British Thermal Units (MMBTU) and would generate 750–6,800 cubic meters of product water depending on the treatment technology. Additionally, based on the thermal technologies assessed in this study, the theoretical maximum volume of product water that can be generated statewide using the energy from the flared gas in 2012 is 180–540 million cubic meters, representing approximately 3–9% of the state’s annual water demand for municipal purposes or 1–2.4% of total statewide water demand for all purposes. This is enough gas to treat more water than was projected would be used for the entire mining sector in 2010 in Texas. For the analysis coupling renewable electricity with on-site treatment, the necessary energy for water management upstream and downstream of a well site was calculated and compared with the current energy requirements and those of a proposed strategy where a portion of the wastewater is treated on-site and reused on a subsequent well. Through this analysis, it was determined that implementing on-site treatment using renewable electricity could reduce freshwater requirements by 11–26%. Finally, it was calculated that this approach could displace approximately 16% of the fossil fuel energy requirements for pumping freshwater, trucking that water to the well site, and trucking wastewater to a disposal well. / text