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Tesis por compendio, En la última década se ha producido un cambio social de gran relevancia en el ámbito del medio ambiente. Nuestra sociedad es cada vez más consciente del concepto de desarrollo sostenible. Aspectos como la economía circular están adquiriendo gran importancia y ello implica un uso adecuado de los recursos naturales y de los residuos que se generan en diversas actividades empresariales. La industria del algodón siempre ha tenido como producto principal la fibra de algodón; no obstante, la planta del algodón también incluye el tallo y las semillas. Parte de las semillas se emplean para re-siembra, pero el resto da lugar a un subproducto de grandes volúmenes que se emplea como complemento alimenticio para animales. La semilla de algodón es rica en ácidos grasos insaturados, proteínas y componentes lignocelulósicos. Si bien es posible obtener aceite de semilla de algodón para uso alimenticio, los procesos de refino son complejos y caros y, dado que el principal producto de la industria algodonera es la fibra, los cultivos de esta planta no están sujetos a las restrictivas reglamentaciones de otros cultivos utilizados, principalmente, en alimentación. Esta tesis doctoral explora las posibilidades de las semillas de algodón como material base para la obtención de polímeros y aditivos de polímeros para el desarrollo de formulaciones de plásticos más respetuosas con el medio ambiente. En la presente tesis doctoral se exploran diversas posibilidades de modificación del aceite de semilla de algodón para la obtención de resinas termoestables, aditivos plastificantes para polímeros termoplásticos, agentes compatibilizantes y harinas de refuerzo para compuestos. Dado el perfil lipídico del aceite de semilla de algodón, con alto contenido en ácidos grasos monoinsaturados y poliinsaturados, es posible llevar a cabo diversas modificaciones químicas. Se ha trabajado en el proceso de epoxidación con el empleo de peroxoácidos generados in situ y se ha procedido a optimizar los parámetro, In the last decade a social change of great relevance in the field of environment has been detected. Our society is increasingly aware of the concept of sustainable development. Some topics such as the circular economy are gaining great importance and this implies a proper use of natural resources and an appropriate waste management. The main product of the cotton industry has been traditionally the cotton fiber; However, the cotton plant also includes the stem and seeds. Part of the seeds are used for re-seeding, but the rest results in a by-product of large volumes which is used as a food supplement for animals. The cottonseed contains high amounts of unsaturated fatty acids, proteins and lignocellulosic components. While it is possible to obtain oil from cottonseed for alimentary use, the refining processes are complex and expensive, and since the main product of the cotton industry is fiber, the crops of this plant are not subjected to the restrictive regulations of other crops whose main market is food industry. This doctoral thesis explores the possibilities of cottonseed as a base renewable material for obtaining polymers and polymer additives for the development industrial of formulations more respectful with the environment. In the present thesis different possibilities of modification of cottonseed oil are explored with the aim of obtaining thermosetting resins, plasticizer additives for thermoplastics polymers, compatibilizers agents and flours/powder for reinforcement in composites. Given the lipid profile of cottonseed oil, with high content of monounsaturated and polyunsaturated fatty acids, it is possible to carry out different chemical modifications. One of these processes is epoxidation using peroxy acids generated in-situ which has been optimized in terms of process parameters in order to obtain the best epoxidation yielding. These epoxidized oils have been used as thermosetting resins (resins with epoxy type functionality) and as plasticizers in s, En l'última dècada s'ha produït un canvi social de gran rellevància en l'àmbit del medi ambient. La nostra societat és, cada vegada, més conscient del concepte de desenvolupament sostenible. Aspectes com ara l'economia circular estan adquirint gran importància i això implica un ús adequat dels recursos naturals i dels residus que es generen en diverses activitats empresarials. La indústria del cotó sempre ha tingut com a producte principal la fibra de cotó; no obstant això, la planta de cotó també inclou la tija i les llavors. Part de les llavors s'utilitzen en el procés de sembra, però la resta constitueix un subproducte de gran volum que s'utilitza com a complement alimentari per a animals. La llavor de cotó és rica en àcids grassos saturats, proteïnes i components lignocel·lulòsics. Si bé és cert que es pot obtenir oli de llavor de cotó per a ús alimentari, els processos de refinament son complexes i cars i, donat que el principal producte de la indústria del cotó és la fibra, els cultius d'aquesta planta no estan subjectes a les restrictives reglamentacions d'altres cultius utilitzats, principalment, en alimentació. Aquesta tesi doctoral explora les possibilitats de les llavors de cotó com a material base per a l'obtenció de polímers i additius de polímers per al desenvolupament de formulacions de plàstics més respectuoses amb el medi ambient. En la present tesi doctoral, s'exploren diverses possibilitats de modificació de l'oli de la llavor de cotó per a l'obtenció de resines termoestables, additius plastificants per a polímers termoplàstics, agents compatibilitzants i farines de reforç per a compostos. Donat el perfil lipídic de l'oli de llavor de cotó, amb un alt contingut d'àcids grassos mono insaturats i poli insaturats, és possible dur a terme diferents modificacions químiques. S'ha treballat en el procés d'epoxidació amb la utilització de peroxoàcids generats in situ i s'ha procedit a optimitzar els paràmetres de l'esmentat procés amb la finalitat d'obten

[EN] Poly(3-hydroxybutyrate) is a biodegradable aliphatic polyester obtained through bacterial fermentation that has gained attention in the last few years; nevertheless, its industrial applications are restricted because of some drawbacks related to its high stiffness and fragility which is associated to its high crystallinity. In this work, poly(3-hydroxybutyrate) (P3HB) was melt blended with poly(e-caprolactone) (PCL) at a constant weight ratio of 75/25 (P3HB/PCL) by reactive extrusion with different contents of dicumyl peroxide (DCP) in the 0 1 wt% range. The effects of the DCP load on mechanical, thermal and morphology of the P3HB/PCL blend were studied. Results showed a positive increase in the elongation at break and the impact-absorbed energy of 91% and 231% respectively with regard the uncompatibilized P3HB/PCL blend by the addition of 1 wt% DCP, being this a clear evidenced of the improved compatibility between these polymers. Moreover, morphology of DCP-compatibilized P3HB/PCL blend obtained by field emission electron microscopy (FESEM) and atomic force microscopy (AFM) showed a remarkable decrease in the particle size of poly(e-caprolactone)-rich domains randomly dispersed in the poly(3-hydroxybutyrate). In addition, both FESEM and AFM also revealed improved interfacial adhesion between P3HB- and PCL-rich phases with a noticeable decrease in the gap between them. Addition of 1 wt% DCP also contributes to lowering the degree of crystallinity of PHB by 14% in the blend and other thermal properties are not highly affected by the reactive extrusion with DCP. ©2016 Elsevier Ltd. All rights reserved.

[EN] During the accomplishment of the “Material science” laboratory practices in the Degree of Chemical Engineering, we have incorporated the use of the multi-platform application “Kahoot!” to evaluate the subject. The incorporation of this application improves the attention of the student during the development of the laboratory practices in an efficient and dynamic way. Furthermore, the application allows individual participation of students and debate between them in a dynamic and entertaining mode. The application improves student collaboration and attention in the development of the practices. The implementation of the multi-platform application “Kahoot!” encourages the attention and participation of the student in the laboratory practices in a very effective way., [ES] Durante la realización de las prácticas de laboratorio de la asignatura de “Ciencia de Materiales” en el Grado de Ingeniería Química se ha incorporado el uso de la aplicación multiplataforma Kahoot! para su evaluación. Con la incorporación de esta aplicación se consigue incrementar la atención del alumno de forma efectiva y dinámica durante el desarrollo de las mismas. Además la aplicación permite tanto la participación individual como el debate entre los propios alumnos de manera dinámica y entretenida, mejorando la colaboración y la atención del alumno en el transcurso de las prácticas. Con la implementación de la aplicación multiplataforma Kahoot! se fomenta la atención y participación del alumnado en las clases prácticas de una forma muy efectiva.

[EN] During the academic year 2016-17 the flipped classroom methodology was implemented using the GOOGLE CLASS platform in the "waste treatment" subject. This methodology has allowed students to have more time in the classroom to solve doubts and practical problems, increasing collaborative work. Using this methodology, the self-assessment test score increased compared to other years and students prefer this methodology to the traditional master class as indicated in an anonymous survey., [ES] Durante el curso académico 2016-17 se ha implantado la metodología de clase inversa utilizando la plataforma GOOGLE CLASSROOM en la asignatura "Tratamiento de Residuos". Esta metodología ha permitido que los alumnos dispongan de más tiempo en el aula para resolver dudas y realizar prácticas, aumentando el trabajo colaborativo. Mediante esta metodología la nota media del test de autoevaluación subió respecto a otros años y los alumnos prefieren está metodología a la tradicional clase magistral según indicaron en una encuesta anónima.

The aim of this study was to analyze the durability of a plasma treatment on the surface of poly(lactic acid) (PLA). We used atmospheric-plasma treatment with air to improve the wettability of PLA by evaluating the aging effect under controlled conditions of relative humidity (RH) and temperature (25% RH and 258C). We studied the durability of the atmospheric-plasma treatment by measuring the contact angle, calculating the surface energy, and observing changes in the resistance of the PLA PLA adhesive bonds. These techniques allowed us to evaluate the hydrophobic recovery phenomenon that the PLA surface suffered as a consequence of the aging process. The results provide the maximum storage time of PLA treated with atmospheric plasma at which the sample retained its good AQ5 adhesion properties; this time was lower than 3 days under normal atmospheric conditions. V

This is the accepted version of the following article: Garcia-Garcia, D., Carbonell-Verdu, A., Jordá-Vilaplana, A., Balart, R. and Garcia-Sanoguera, D. (2016), Development and characterization of green composites from bio-based polyethylene and peanut shell. J. Appl. Polym. Sci. 43940 doi: 10.1002/app.43940, which has been published in final form at http://dx.doi.org/10.1002/app.43940, [EN] In the present work, different compatibilizers, namely polyethylene-graft-maleic anhydride (PE-g-MA), polypropylene-graftmaleic anhydride (PP-g-MA), and polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene-graft-maleic anhydride (SEBS-g-MA) were used on green composites derived from biobased polyethylene and peanut shell (PNS) flour to improve particle polymer interaction. Composites of high-density polyethylene/peanut shell powder (HDPE/PNS) with 10 wt % PNS flour were compatibilized with 3 wt % of the abovementioned compatibilizers. As per the results, PP-g-MA copolymer lead to best optimized properties as evidenced by mechanical characterization. In addition, best particle matrix interface interactions with PP-g-MA were observed by scanning electron microscopy (SEM). Subsequently HDPE/PNS composites with varying PNS flour content in the 5 30 wt % range with PP-g-MA compatibilizer were obtained by melt extrusion and compounding followed by injection molding and were characterized by mechanical, thermal, and morphological techniques. The results showed that PNS powder, leads to an increase in mechanical resistant properties (mainly, flexural modulus, and strength) while a decrease in mechanical ductile properties, that is, elongation at break and impact absorbed energy is observed with increasing PNS flour content. Furthermore, PNS flour provides an increase in thermal stability due to the natural antioxidant properties of PNS. In particular, composites containing 30 wt % PNS powder present a flexural strength 24% and a flexural modulus 72% higher than the unfilled polyethylene and the thermo-oxidative onset degradation temperature is increased from 232 8C up to 2548C thus indicating a marked thermal stabilization effect. Resultant composites can show a great deal of potential as base materials for wood plastic composites.

This is the accepted version of the following article: Carbonell-Verdu, A., Garcia-Sanoguera, D., Jordá-Vilaplana, A., Sanchez-Nacher, L. and Balart, R. (2016), A new biobased plasticizer for poly (vinyl chloride) based on epoxidized cottonseed oil. J. Appl. Polym. Sci., 133, 43642, doi: 10.1002/app.43642, which has been published in final form at http://dx.doi.org/10.1002/app.43642, [EN] The use of epoxidized cottonseed oil (ECSO) as plasticizer for poly(vinyl chloride), PVC was studied. The plasticizer content was set to 70 phr and the optimum isothermal curing conditions were studied in the temperature range comprised between 160 ºC and 220 ºC with varying curing times in the 7.5 - 17.5 min range. The influence of the curing conditions on overall performance of cured plastisols was followed by the evolution of mechanical properties (tensile tests with measurements of tensile strength, elongation at break and modulus), change in colour, surface changes of fractured samples by scanning electron microscopy (SEM), thermal transitions by differential scanning calorimetry (DSC) and migration in n-hexane. The optimum mechanical features of cured plastisols are obtained for curing temperatures in the 190-220 ºC range. For these curing conditions, fractography analysis by SEM gives evidences of full curing process as no PVC particles and free plasticizer can be found.

En esta investigación se propone una metodología para obtener una resina termoestable a partir de aceite de semilla de algodón (ASA) mediante el proceso de epoxidación. La influencia del ratio de peróxido y tiempo de epoxidación, han sido seguidos mediante el índice de yodo y oxígeno. Se ha conseguido un rendimiento de más del 83%, frente a los valores teóricos, durante la epoxidación llevada a cabo con el mayor ratio de peróxido. El proceso de reticulación, de la mezcla en estado líquido del aceite epoxidado con mezclas de dos endurecedores (DDSA : MNA), ha sido seguido mediante el tiempo de gel y reometría oscilatoria para las temperaturas de 110 y 120ºC.

El objetivo principal de este trabajo es la obtención de Wood Plastic Composites (WPC) biobasados con matriz de ácido poliláctico (PLA) y refuerzo de cáscara de avellana. Se han realizado cuatro formulaciones con distintos porcentajes en peso tanto de ácido poliláctico como de cáscara de avellana. Los diferentes compuestos han sido caracterizados mecánicamente mediante un test de impacto y otro de dureza. Las fracturas obtenidas han sido observadas mediante microscopia electrónica de barrido (SEM). El análisis de los resultados indica una falta de interacción entre la matriz de PLA y la partícula de cáscara de avellana.

Biobased composites were fabricated with waste of tiger nut natural fibers, different binder fibers (lyocell and cotton) and thermo-bonding fibers (PLA, HDPE, PA6-CoPA). These composites were processed by wet-laid process and hot-press molding process. The obtained composites were characterized by flexural, hardness and Charpy impact tests. The internal structure of the composite was analyzed by SEM observing a significant heterogeneity. The high fiber content (80% wt) and the lack of a continuous matrix phase causes mediocre mechanical response of the material. Thermo-bonding fibers kind are more influential than the binder fibers. The best mechanical responses were obtained with additions of PLA fibers thermo-bonding fibers. Flexural modulus was maximum (865 MPa) for 80%wt tiger nut/10% wt binder fiber / 10% PLA fiber composite.

The packaging industry generates a high volume of wastes; so that, there is a high demand of biodegradable materials, which do not damage the environment. Nowadays, there is an interesting consumption of polylactic acid (PLA) due to its biodegradable features. This work focuses on the improvement of mechanical properties of PLA adhesion joints for uses in the packaging industry. In order to achieve that purpose, atmospheric plasma treatment is used to selectively modify PLA surface properties. The obtained experimental results show that the atmospheric plasma treatment is suitable to increase the mechanical performance of PLA-PLA adhesive joints. Optimum conditions for the atmospheric plasma treatment were obtained with a nozzle-substrate distance of 10 mm and an advance rate in the 100-300 mm s(-1) range; for these particular conditions, the effectiveness of the surface modification is the highest. The main plasma-acting mechanisms are microetching together with the insertion of polar groups which lead to an interesting synergy that causes a remarkable increase in mechanical properties of adhesion joints. In particular, the shear strength of untreated PLA-PLA adhesion joints is close to 50 N cm(-2) and this value is increased up to values of about 168.7 N cm(-2) with optimum plasma treatment conditions. This indicates that atmospheric plasma treatment is both a technical and an environmental friendly technique to improve mechanical performance of PLA adhesive joints. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42391.

Green composites were prepared with polypropylene matrix and 20 wt.% spent coffee ground (SCG) powder for uses as a wood plastic composite (WPC). The effects of hydrophobic treatment with palmitoyl chloride on SCG powder is compared with conventional surface treatment based on silanization with (3-glycidyloxypropyl) trimethoxysilane and the use of a maleated copolymer compatibilizer (polypropylene-graft-maleic anhydride, PP-g-MA) in terms of mechanical properties, morphology, thermal properties and water uptake. Composites were previously mixed in a twin-screw co-rotating extruder and subsequently subjected to injection moulding. The comparative effect of the different surface treatments and or compatibilizers on mechanical performance was studied by flexural, impact tests and dynamic mechanical thermal analysis (DMTA-torsion); in addition, the stabilizing effect of SCG was revealed by differential scanning calorimetry (DSC) and thermogravymetric analysis (TGA). As one of the main drawbacks of wood plastic composites and natural fibre reinforced plastics is the moisture gain, water uptake tests were carried out in order to quantify the effectiveness of the hydrophobization process with palmitoyl chloride. Results show a slight increase in flexural modulus for composites with both untreated and treated/compatibilized SCG powder (20 wt.%). As expected, thermal stability is improved as indicated by an increase of more than 8% in the onset degradation temperature by DSC if compared to unfilled polypropylene. Fracture analysis by scanning electron microscopy (SEM) shows better particle dispersion for PP-SCG composites with hydrophobized SCG with palmitoyl chloride treatment; in addition a remarkable decrease in water uptake is observed for composites with hydrophobized SCG. ©2015 Elsevier Ltd. All rights reserved.

The continuous rise in oil prices has led to the use of other ways to obtain polymer materials. This paper proposes a methodology to obtain a thermosetting resin from cottonseed oil by epoxidation process. The cottonseed oil contains as most representative fatty acids: 52.5% of linoleic acid (C18: 2), 23.9% of palmitic acid (C16: 0) and 17.6% of oleic acid (C18: 1); the real iodine index, which is indicative of the number of double bonds, has a value of 107. Epoxidized cottonseed oil (ECSO) has been successfully obtained using conventional epoxidation process with hydrogen peroxide, acetic acid and sulfuric acid, maintaining a constant temperature of 70 °C with homogeneous magnetic stirring. Average oxirane oxygen content (OOC) of 5.32% can be obtained by conventional epoxidation process which represents a yield over 83%. The epoxidized oil has been crosslinked with mixtures of two cyclic anhydrides to tailor different properties on final crosslinked thermosetting resins: on the one hand, methyl nadic anhydride (MNA) which is characterized by a rigid molecular structure and on the other hand, dodecenylsuccinic anhydride (DDSA) with a long side chain that can confer flexibility. The crosslinking process has been followed by dynamic differential scanning calorimetry (DSC), ionic mobility and oscillatory rheometry (OR) as well as gel time determination. The effect of the hardener mixture (wt.% DDSA:MNA) on mechanical performance of cured materials has been followed by flexural and impact tests as well as the evolution of the storage modulus (G′) by dynamic mechanical analysis (DMA) in torsion mode. By selecting the appropriate hardener mixture, it is possible to obtain crosslinked materials with different properties ranging from stiff matrices for ECSO crosslinked with MNA to flexible matrices for ECSO cured with DDSA. This has occurred with other thermosetting resins like epoxidized soy bean oil (ESBO) or epoxidized linseed oil (ELO). (C) 2014 Elsevier Ltd. All

During the last decade the use of fiber reinforced composite materials has consolidated as an attracting alternative to traditional materials due to an excellent balance between mechanical properties and lightweight. One drawback related to the use of inorganic fibers such as those derived from siliceous materials is the relative low compatibility with conventional organic polymer matrices. Surface treatments with coupling agents and the use of copolymers allow increasing fiber-matrix interactions which has a positive effect on overall properties of composites. In this research work we report the use of slate fiber treated with different coupling agents as reinforcement for high density polyethylene from sugarcane. A silane (propyltrimethoxy silane; PTMS) and a graft copolymer (polyethylene-graft-maleic anhydride; PE-g-MA) were used to improve fiber-matrix interactions on HOPE-slate fiber. The effect of the different compatibilizing systems and slate fiber content were evaluated by scanning electron microscopy (SEM), dynamic thermomechanical analysis (DTMA) as well as mechanical properties (tensile, flexural and impact). The results show that the use of silane coupling agents leads to higher fiber-matrix interactions which has a positive effect on overall mechanical properties. Interesting results are obtained for composites containing 30 wt.% slate fiber previously treated with propyltrimethoxy silane (PTMS) with an increase in tensile and flexural strength of about 16% and 18% respectively. (C) 2014 Elsevier Ltd. All rights reserved.

[ES] El proyecto plantea un aprovechamiento integral de un residuo industrial derivado del procesado del algodón, concretamente, el aceite de semilla de algodón (CSO). Si bien se trata de un triglicérido con unas propiedades atractivas debido a la presencia de diferentes grupos insaturados en su estructura (derivados de ácido oleico y linoleico, fundamentalmente), estas insaturaciones no son lo suficientemente reactivas para utilizarse de forma directa. Por ello, el proyecto plantea llevar a cabo procesos de conversión de la estructura de aceite vegetal en una estructura de aceite vegetal epoxidado (EVO) por conversión de las insaturaciones en grupos oxirano con el empleo de ácido acético y peróxido de hidrógeno. Se pretende utilizar el aceite de semilla de algodón epoxidado (ECSO) como resina base de tipo termoestable que puede entrecruzarse con anhídridos convencionales (anhídrido metil nádico, anhídrido dodecenil succínico).

El uso actual de materiales para aplicación en biomedicina, concretamente para el sector protésico, está siendo condicionado, en los últimos años, por una serie de requisitos que no cumplen los materiales tradicionales. Éstos deben ser mecánicamente resistentes, rígidos con cierta elasticidad, biodegradables y/o bioabsorbibles por el medio fisiológico. Los composites base polimérica, en concreto las mezclas de PLA/PCL presentan características muy prometedoras para la fabricación de fijaciones de uso en biomedicina. El uso de este tipo de materiales conlleva beneficios tales como evitar segundas intervenciones quirúrgicas para retirar, una vez regenerado el hueso, las fijaciones o tornillos incorporados. El objetivo de este trabajo ha sido caracterizar los composites fabricados, obteniendo las propiedades mecánicas para adaptar éstos materiales a su futura aplicación como fijaciones necesarias en biomedicina para la reparación de roturas óseas.

En este trabajo se ha estudiado que agente de acoplamiento se debe utilizar para desarrollar un nuevo material compuesto de origen totalmente natural. El nuevo material compuesto utiliza como matriz un polietileno de base biológica y como material de refuerzo se ha utilizado cáscara de huevo (CH). Se ha utilizado CH con el fin de reemplazar mineral de carbonato cálcico como carga de polímero, que se utiliza comúnmente. Para mejorar la adhesión entre la matriz y la carga se ha evaluado el uso de tres agentes de acoplamiento (silano, titanato y circonato) con el fin de escoger el que mejore las características del composite.

Debido a los altos costes económicos y a los riesgos ambientales de los productos derivados del petróleo en los últimos años hay una creciente tendencia en la investigación, desarrollo y fabricación de biocomposites. Los biocomposites son aquellos materiales en los que al menos uno de los componentes, ya sea la matriz o el refuerzo, proviene de origen renovable. En este estudio se ha utilizado como matriz un biopolímero de polietileno verde obtenido a partir de etanol de caña de azúcar y, como material de refuerzo se ha utilizado fibra de plumero de la pampa. Las propiedades mecánicas de los materiales compuestos se evaluaron mediante ensayos estandarizados de flexión y tracción. El comportamiento térmico del mismo mediante Calorimetría Diferencial de Barrido (DSC). Para justificar el comportamiento mecánico se estudió la morfología de las muestras por microscopía electrónica de barrido (SEM).

El objetivo que se persigue con el presente proyecto es reutilizar los neumáticos de los camiones, una vez han cumplido su misión primaria, y suplir, al mismo tiempo, el peligro que suponen los guardarrailes actuales en nuestras carreteras, especialmente para vehículos de dos ruedas tales como motocicletas y bicicletas. Con ello se podría poner fin a dos importantes problemas como son los desechos causados en el mundo del motor y tratar de prevenir y/o evitar aumentar las listas negras tan elevadas de nuestro país., Para llevar a cabo el objetivo planteado se tendrá que diseñar una máquina para el corte de neumáticos utilizados de camión, obteniendo de ellos la banda de rodadura, la cual se colocará en los guardarrailes de las carreteras.