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This paper addresses the major concern which component porosity represents in Vacuum Infusion (VI) manufacturing due to resin gelation at pressures close to absolute vacuum. Degassing is a fundamental step to minimize or even avoid resin outgassing and enhance dissolution of voids created during preform impregnation. The efficacy of different degassing procedures based on vacuum degassing, and assisted by adding a nucleation medium, High Speed (HS) resin stirring and/or later pressurization during different time intervals have been analyzed in terms of final void content is studied. Through a rigorous and careful design of the manufacturing process, outgassing effects on final void content were isolated from the rest of porosity causes and specimens with two clearly identifiable regions in terms of porosity were manufactured to facilitate its analysis. Maximum void content was kept under 4% and porous area size was reduced by 72% with respect to conventional vacuum degassing when resin was stirred at HS; therefore, highlighting the importance of enhancing bubble formation during degassing.
Jaime Juan; Arlindo Silva; Jose Antonio Tornero; Jose Gámez; Nuria Salán. Void Content Minimization in Vacuum Infusion (VI) via Effective Degassing. Polymers 2021, 13, 2876 .
AMA StyleJaime Juan, Arlindo Silva, Jose Antonio Tornero, Jose Gámez, Nuria Salán. Void Content Minimization in Vacuum Infusion (VI) via Effective Degassing. Polymers. 2021; 13 (17):2876.
Chicago/Turabian StyleJaime Juan; Arlindo Silva; Jose Antonio Tornero; Jose Gámez; Nuria Salán. 2021. "Void Content Minimization in Vacuum Infusion (VI) via Effective Degassing." Polymers 13, no. 17: 2876.
Fiber–matrix interfacial adhesion is one of the key factors governing the final properties of natural fiber-based polymer composites. In this work, four extrusion reactive agents were tested as potential compatibilizers in polyhydroxylbutyrate (PHB)/cellulose composites: dicumyl peroxide (DCP), hexamethylene diisocyanate (HMDI), resorcinol diglycidyl ether (RDGE), and triglycidyl isocyanurate (TGIC). The influence of the fibers and the different reactive agents on the mechanical properties, physical aging, and crystallization behavior were assessed. To evaluate the compatibilization effectiveness of each reactive agent, highly purified commercial cellulose fibers (TC90) were used as reference filler. Then, the influence of fiber purity on the compatibilization effect of the reactive agent HMDI was evaluated using untreated (U_RH) and chemically purified (T_RH) rice husk fibers, comparing the results with the ones using TC90 fibers. The results show that reactive agents interact with the polymer matrix at different levels, but all compositions showed a drastic embrittlement due to the aging of PHB. No clear compatibilization effect was found using DCP, RDGE, or TGIC reactive agents. On the other hand, the fiber–polymer interfacial adhesion was enhanced with HMDI. The purity of the fiber played an important role in the effectiveness of HMDI as a compatibilizer, since composites with highly purified fibers showed the greatest improvements in tensile strength and the most favorable morphology. None of the reactive agents negatively affected the compostability of PHB. Finally, thermoformed trays with good mold reproducibility were successfully obtained for PHB/T_RH/HMDI composition.
Estefanía Lidón Sánchez-Safont; Abdulaziz Aldureid; José María Lagarón; Luis Cabedo; José Gámez-Pérez. Study of the Compatibilization Effect of Different Reactive Agents in PHB/Natural Fiber-Based Composites. Polymers 2020, 12, 1967 .
AMA StyleEstefanía Lidón Sánchez-Safont, Abdulaziz Aldureid, José María Lagarón, Luis Cabedo, José Gámez-Pérez. Study of the Compatibilization Effect of Different Reactive Agents in PHB/Natural Fiber-Based Composites. Polymers. 2020; 12 (9):1967.
Chicago/Turabian StyleEstefanía Lidón Sánchez-Safont; Abdulaziz Aldureid; José María Lagarón; Luis Cabedo; José Gámez-Pérez. 2020. "Study of the Compatibilization Effect of Different Reactive Agents in PHB/Natural Fiber-Based Composites." Polymers 12, no. 9: 1967.
Poly(hydroxybutyrate‐co‐valerate) (PHBV) is a biopolymer that has gained a lot of attention because of its biodegradability, good thermal resistance, and balanced mechanical properties with respect to some commodity plastics. However, it presents two big limitations that hinder its potential application in replacing plastics for rigid injected parts: high cost and low toughness. Aiming at overcoming these limitations, the use of two additives in a PHBV matrix was explored: thermoplastic polyurethane (TPU) as an impact modifier and cellulose as reinforcing filler. Compounds of PHBV with different TPUs and cellulose contents were prepared by extrusion and, subsequently, injection molding. The morphology, thermal, and mechanical properties of the so‐obtained materials were analyzed. Also, the biodisintegrability under standard composting conditions of the studied compositions was also assessed. The results of this work show that the obtained PHBV/TPU/cellulose compounds are biodisintegrable and show balanced properties in terms of thermal resistance–stiffness–toughness. These properties point these compounds as potential candidates to replace commodities in rigid part applications that require biodisintegration in their end‐of‐life, being able to be processed in a conventional injection molding industrial facility. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 136, 47257.
Estefanía Lidón Sánchez-Safont; Alex Arrillaga; Jon Anakabe; Jose Gamez-Perez; Luis Cabedo. PHBV/TPU/cellulose compounds for compostable injection molded parts with improved thermal and mechanical performance. Journal of Polymer Science 2018, 136, 1 .
AMA StyleEstefanía Lidón Sánchez-Safont, Alex Arrillaga, Jon Anakabe, Jose Gamez-Perez, Luis Cabedo. PHBV/TPU/cellulose compounds for compostable injection molded parts with improved thermal and mechanical performance. Journal of Polymer Science. 2018; 136 (13):1.
Chicago/Turabian StyleEstefanía Lidón Sánchez-Safont; Alex Arrillaga; Jon Anakabe; Jose Gamez-Perez; Luis Cabedo. 2018. "PHBV/TPU/cellulose compounds for compostable injection molded parts with improved thermal and mechanical performance." Journal of Polymer Science 136, no. 13: 1.
Poly(3-hydroxybutyrate-co-3-valerate), PHBV, is a bacterial thermoplastic biopolyester that possesses interesting thermal and mechanical properties. As it is fully biodegradable, it could be an alternative to the use of commodities in single-use applications or in those intended for composting at their end of life. Two big drawbacks of PHBV are its low impact toughness and its high cost, which limit its potential applications. In this work, we proposed the use of a PHBV-based compound with purified α-cellulose fibres and a thermoplastic polyurethane (TPU), with the purpose of improving the performance of PHBV in terms of balanced heat resistance, stiffness, and toughness. Three reactive agents with different functionalities have been tested in these compounds: hexametylene diisocianate (HMDI), a commercial multi-epoxy-functionalized styrene-co-glycidyl methacrylate oligomer (Joncryl® ADR-4368), and triglycidyl isocyanurate (TGIC). The results indicate that the reactive agents play a main role of compatibilizers among the phases of the PHBV/TPU/cellulose compounds. HMDI showed the highest ability to compatibilize the cellulose and the PHBV in the compounds, with the topmost values of deformation at break, static toughness, and impact strength. Joncryl® and TGIC, on the other hand, seemed to enhance the compatibility between the fibres and the polymer matrix as well as the TPU within the PHBV.
Estefanía Lidón Sánchez-Safont; Alex Arrillaga; Jon Anakabe; Luis Cabedo; Jose Gamez-Perez. Toughness Enhancement of PHBV/TPU/Cellulose Compounds with Reactive Additives for Compostable Injected Parts in Industrial Applications. International Journal of Molecular Sciences 2018, 19, 2102 .
AMA StyleEstefanía Lidón Sánchez-Safont, Alex Arrillaga, Jon Anakabe, Luis Cabedo, Jose Gamez-Perez. Toughness Enhancement of PHBV/TPU/Cellulose Compounds with Reactive Additives for Compostable Injected Parts in Industrial Applications. International Journal of Molecular Sciences. 2018; 19 (7):2102.
Chicago/Turabian StyleEstefanía Lidón Sánchez-Safont; Alex Arrillaga; Jon Anakabe; Luis Cabedo; Jose Gamez-Perez. 2018. "Toughness Enhancement of PHBV/TPU/Cellulose Compounds with Reactive Additives for Compostable Injected Parts in Industrial Applications." International Journal of Molecular Sciences 19, no. 7: 2102.
The new educational paradigm has led to a change in the teaching methodologies toward those more focused on the student, among these, project-based learning (PBL) is postulated as one of the most promising. This work is focused on the description of the experience of using PBL methodology in Materials Science courses, conducted by four different Spanish universities on different engineering degrees. The other main objective is to analyse and evaluate how the PBL was perceived by the students and the lecturers that took part in the PBL process. This investigation was an embedded, sequential mixed-methods study, which began by administering a survey to one hundred and four students and then a focus group with six students and six lecturers in four different engineering degrees of four Universities. Results generally show a good degree of acceptance of this approach by all parties involved.
Lidón Moliner; Luis Cabedo; Marta Royo; Jose Gámez-Pérez; Pablo Lopez-Crespo; Mercè Segarra; Teresa Guraya. On the perceptions of students and professors in the implementation of an inter-university engineering PBL experience. European Journal of Engineering Education 2018, 44, 726 -744.
AMA StyleLidón Moliner, Luis Cabedo, Marta Royo, Jose Gámez-Pérez, Pablo Lopez-Crespo, Mercè Segarra, Teresa Guraya. On the perceptions of students and professors in the implementation of an inter-university engineering PBL experience. European Journal of Engineering Education. 2018; 44 (5):726-744.
Chicago/Turabian StyleLidón Moliner; Luis Cabedo; Marta Royo; Jose Gámez-Pérez; Pablo Lopez-Crespo; Mercè Segarra; Teresa Guraya. 2018. "On the perceptions of students and professors in the implementation of an inter-university engineering PBL experience." European Journal of Engineering Education 44, no. 5: 726-744.
The suitability of three local lignocellulosic wastes i.e. almond shell (AS), rice husk (RH) and seagrass (SG) as fillers in PHB/Fiber composites applications has been studied. PHB/Fiber composites with 10 phr and 20 phr fiber content were prepared by melt blending. The influence of the fiber type (size, morphology and origin) and content on the morphological, mechanical and thermal properties of the as obtained composites has been assessed. To evaluate the potential use in food packaging applications, the barrier performance to water, thermoforming ability and disintegration in controlled composting conditions of the composites were also studied. All the fibers have demonstrated to be apt for their use as fillers in PHB/Fiber composites, showing a reinforcing effect without affecting the crystallinity and the disintegration rate of PHB. The thermal stability and the water barrier performance of the composites were reduced by the presence of the fibers. Nevertheless, the addition of AS resulted in the best balance of properties, in terms of permeability and mechanical properties, finding an enhancement of the thermoforming ability of PHB when 10 phr of AS was added.
Estefanía Lidón Sánchez-Safont; Abdulaziz Aldureid; José María Lagarón; Jose Gamez-Perez; Luis Cabedo. Biocomposites of different lignocellulosic wastes for sustainable food packaging applications. Composites Part B: Engineering 2018, 145, 215 -225.
AMA StyleEstefanía Lidón Sánchez-Safont, Abdulaziz Aldureid, José María Lagarón, Jose Gamez-Perez, Luis Cabedo. Biocomposites of different lignocellulosic wastes for sustainable food packaging applications. Composites Part B: Engineering. 2018; 145 ():215-225.
Chicago/Turabian StyleEstefanía Lidón Sánchez-Safont; Abdulaziz Aldureid; José María Lagarón; Jose Gamez-Perez; Luis Cabedo. 2018. "Biocomposites of different lignocellulosic wastes for sustainable food packaging applications." Composites Part B: Engineering 145, no. : 215-225.
Luis Cabedo; Miguel A. Cerqueira; Jose A. Covas; Malco C. Cruz-Romero; Henriette M.C. De Azeredo; Maria Clea B. Figueirêdo; Elena Fortunati; Roland Franz; Jose Gamez-Perez; Diana Gregor-Svetec; Loic Hilliou; Josè M. Kenny; Joseph P. Kerry; Jose M. Lagaron; Francesca Luzi; Michael A. Morris; Sibu C. Padmanabhan; Lorenzo M. Pastrana; Yolanda Picó; Fátima Poças; Debora Puglia; Bettina Röcker; Morsyleide F. Rosa; Luigi Torre; Sergio Torres-Giner; António A. Vicente; Weijun Yang; Selçuk Yildirim; Selçuk Yıldırım. Contributors. Nanomaterials for Food Packaging 2018, 1 .
AMA StyleLuis Cabedo, Miguel A. Cerqueira, Jose A. Covas, Malco C. Cruz-Romero, Henriette M.C. De Azeredo, Maria Clea B. Figueirêdo, Elena Fortunati, Roland Franz, Jose Gamez-Perez, Diana Gregor-Svetec, Loic Hilliou, Josè M. Kenny, Joseph P. Kerry, Jose M. Lagaron, Francesca Luzi, Michael A. Morris, Sibu C. Padmanabhan, Lorenzo M. Pastrana, Yolanda Picó, Fátima Poças, Debora Puglia, Bettina Röcker, Morsyleide F. Rosa, Luigi Torre, Sergio Torres-Giner, António A. Vicente, Weijun Yang, Selçuk Yildirim, Selçuk Yıldırım. Contributors. Nanomaterials for Food Packaging. 2018; ():1.
Chicago/Turabian StyleLuis Cabedo; Miguel A. Cerqueira; Jose A. Covas; Malco C. Cruz-Romero; Henriette M.C. De Azeredo; Maria Clea B. Figueirêdo; Elena Fortunati; Roland Franz; Jose Gamez-Perez; Diana Gregor-Svetec; Loic Hilliou; Josè M. Kenny; Joseph P. Kerry; Jose M. Lagaron; Francesca Luzi; Michael A. Morris; Sibu C. Padmanabhan; Lorenzo M. Pastrana; Yolanda Picó; Fátima Poças; Debora Puglia; Bettina Röcker; Morsyleide F. Rosa; Luigi Torre; Sergio Torres-Giner; António A. Vicente; Weijun Yang; Selçuk Yildirim; Selçuk Yıldırım. 2018. "Contributors." Nanomaterials for Food Packaging , no. : 1.
Luis Cabedo; Jose Gamez-Perez. Inorganic-Based Nanostructures and Their Use in Food Packaging. Nanomaterials for Food Packaging 2018, 13 -45.
AMA StyleLuis Cabedo, Jose Gamez-Perez. Inorganic-Based Nanostructures and Their Use in Food Packaging. Nanomaterials for Food Packaging. 2018; ():13-45.
Chicago/Turabian StyleLuis Cabedo; Jose Gamez-Perez. 2018. "Inorganic-Based Nanostructures and Their Use in Food Packaging." Nanomaterials for Food Packaging , no. : 13-45.
Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a renewable alternative to conventional barrier packaging polymers due to its thermoplastic properties, biodegradability and gas barrier performance but its potential industrial applications are limited by its high price and difficult processability. A thorough study concerning the thermoforming ability of PHBV, and blends with poly(lactic acid) (PLA) incorporating three different diisocyanates as compatibilizers (hexamethylene diisocyanate, poly(hexamethylene) diisocyanate and 1,4-phenylene diisocyanate) is herein presented after component melt blending. A straightforward universal qualitative method is proposed to assess the thermoformability, based on a visual inspection of a thermoformed specimen and the ability to reproduce the mold shape, and the thermoforming window of the material. The results reveal a significant improvement in the thermoforming capacity and a widening of the thermoforming windows as the correct amounts of diisocyanates are incorporated. The barrier properties and the biodisintegrability of the blends was also studied, confirming a predictable slight decrease of the barrier performance when PLA is added, but without negatively affecting the disintegrability under composting conditions with respect to pristine PHBV
Jennifer González-Ausejo; Estefania Sanchez-Safont; Jose Maria Lagaron; Richard T. Olsson; Jose Gamez-Perez; Luis Cabedo. Assessing the thermoformability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(acid lactic) blends compatibilized with diisocyanates. Polymer Testing 2017, 62, 235 -245.
AMA StyleJennifer González-Ausejo, Estefania Sanchez-Safont, Jose Maria Lagaron, Richard T. Olsson, Jose Gamez-Perez, Luis Cabedo. Assessing the thermoformability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(acid lactic) blends compatibilized with diisocyanates. Polymer Testing. 2017; 62 ():235-245.
Chicago/Turabian StyleJennifer González-Ausejo; Estefania Sanchez-Safont; Jose Maria Lagaron; Richard T. Olsson; Jose Gamez-Perez; Luis Cabedo. 2017. "Assessing the thermoformability of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/poly(acid lactic) blends compatibilized with diisocyanates." Polymer Testing 62, no. : 235-245.
A study concerning the incorporation of sepiolite in blends of biopolyesters (PHBV/PLA) to obtain clay/polymer nanocomposites (CPN) was performed to improve the gas barrier performance of the final materials and achieve a well dispersed morphology by means of an increase in the melt viscosity during melt blending. The latter is relevant to increase the stability of the PHBV sheets during thermoforming. The samples were analyzed using scanning electron microscopy (SEM), wide angle X-ray diffraction (WAXS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), tensile tests at room and high temperatures, dynamo-mechanical thermal analysis in torsion mode (DMTA), oscillatory rheometry with a parallel plate setup, Vicat softening temperature system and oxygen barrier properties. The resulting Sepiolite/PHBV/PLA nanocomposites not only improved the compatibility between the biopolymers and reduced the oxygen permeability, but also improved the mechanical properties at room temperature, showing an increase in the elongation at break, as well as increasing the rigidity and stability of the CPN at higher temperatures, which could make them very attractive for uses in thermoforming applications for food packaging. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers
Jennifer González‐Ausejo; José Gámez‐Pérez; Rafael Balart; José Maria Lagarón; Luis Cabedo. Effect of the addition of sepiolite on the morphology and properties of melt compounded PHBV/PLA blends. Polymer Composites 2017, 40, 1 .
AMA StyleJennifer González‐Ausejo, José Gámez‐Pérez, Rafael Balart, José Maria Lagarón, Luis Cabedo. Effect of the addition of sepiolite on the morphology and properties of melt compounded PHBV/PLA blends. Polymer Composites. 2017; 40 (S1):1.
Chicago/Turabian StyleJennifer González‐Ausejo; José Gámez‐Pérez; Rafael Balart; José Maria Lagarón; Luis Cabedo. 2017. "Effect of the addition of sepiolite on the morphology and properties of melt compounded PHBV/PLA blends." Polymer Composites 40, no. S1: 1.
Resumen En este trabajo se muestra la experiencia docente aplicada a las sesiones de laboratorio de la asignatura de Ciencia y Tecnología de Materiales que se imparte en segundo curso de los grados de Ingeniería Eléctrica, Mecánica y en Tecnologías Industriales en la Universitat Jaume I. El propósito de esta experiencia es facilitar el aprendizaje de los conocimientos teóricos básicos relacionados con la práctica de laboratorio a desarrollar y sensibilizar a los alumnos sobre la importancia de preparar la práctica previamente a su desarrollo. Esto se ha realizado mediante el desarrollo y uso de medios o formatos de trasmisión de los contenidos a conocer previamente a la práctica que sean más atractivos y visuales que el guion de prácticas existente actualmente. Palabras clave: conocimientos previos, visual, evaluación, metodología
Jennifer Gonzalez Ausejo; Raquel Oliver Valls; José Gámez Pérez; Luís Cabedo Mas. Óptimo aprovechamiento de las sesiones de laboratorio. Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red 2017, 1 .
AMA StyleJennifer Gonzalez Ausejo, Raquel Oliver Valls, José Gámez Pérez, Luís Cabedo Mas. Óptimo aprovechamiento de las sesiones de laboratorio. Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red. 2017; ():1.
Chicago/Turabian StyleJennifer Gonzalez Ausejo; Raquel Oliver Valls; José Gámez Pérez; Luís Cabedo Mas. 2017. "Óptimo aprovechamiento de las sesiones de laboratorio." Libro de Actas IN-RED 2017 - III Congreso Nacional de Innovación Educativa y de Docencia en Red , no. : 1.
Jennifer González-Ausejo; Estefania Sánchez-Safont; Luis Cabedo; Jose Gamez-Perez. Erratum: "Toughness Enhancement of Commercial Poly (Hydroxybutyrate-Co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU)". Journal of Multiscale Modelling 2017, 8, 1792002 .
AMA StyleJennifer González-Ausejo, Estefania Sánchez-Safont, Luis Cabedo, Jose Gamez-Perez. Erratum: "Toughness Enhancement of Commercial Poly (Hydroxybutyrate-Co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU)". Journal of Multiscale Modelling. 2017; 8 (1):1792002.
Chicago/Turabian StyleJennifer González-Ausejo; Estefania Sánchez-Safont; Luis Cabedo; Jose Gamez-Perez. 2017. "Erratum: "Toughness Enhancement of Commercial Poly (Hydroxybutyrate-Co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU)"." Journal of Multiscale Modelling 8, no. 1: 1792002.
Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) was blended with poly(lactic acid) (PLA) with various reactive processing agents to decrease its brittleness and enhance its processability. Three diisocyanates, namely, hexamethylene diisocyanate, poly(hexamethylene diisocyanate), and 1,4‐phenylene diisocyanate, were used as compatibilizing agents. The morphology, thermomechanical properties, and rheological behavior were investigated with scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, tensile testing, dynamomechanical thermal analysis in torsion mode (dynamic mechanical analysis), and oscillatory rheometry with a parallel‐plate setup. The presence of the diisocyanates resulted in an enhanced polymer blend compatibility; this led to an improvement in the overall mechanical performance but did not affect the thermal stability of the system. A slight reduction in the PHBV crystallinity was observed with the incorporation of the diisocyanates. The addition of diisocyanates to the PHBV–PLA blend resulted in a notable increase in the final complex viscosity at low frequencies when compared with the same system without compatibilizers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44806.
Jennifer González-Ausejo; Estefania Sánchez-Safont; José Maria Lagarón; Rafael Balart; Luis Cabedo; José Gámez-Pérez. Compatibilization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)-poly(lactic acid) blends with diisocyanates. Journal of Applied Polymer Science 2017, 134, 1 .
AMA StyleJennifer González-Ausejo, Estefania Sánchez-Safont, José Maria Lagarón, Rafael Balart, Luis Cabedo, José Gámez-Pérez. Compatibilization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)-poly(lactic acid) blends with diisocyanates. Journal of Applied Polymer Science. 2017; 134 (20):1.
Chicago/Turabian StyleJennifer González-Ausejo; Estefania Sánchez-Safont; José Maria Lagarón; Rafael Balart; Luis Cabedo; José Gámez-Pérez. 2017. "Compatibilization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)-poly(lactic acid) blends with diisocyanates." Journal of Applied Polymer Science 134, no. 20: 1.
Poly(hydroxyl butyrate-co-valerate) (PHBV) is a biopolymer synthesized by microorganisms that is fully biodegradable with improved thermal and tensile properties with respect to some commodity plastics. However, it presents an intrinsic brittleness that limits its potential application in replacing plastics in packaging applications. Films made of blends of PHBV with different contents of thermoplastic polyurethane (TPU) were prepared by single screw extruder and their fracture toughness behavior was assessed by means of the essential work of fracture (EWF) Method. As the crack propagation was not always stable, a partition method has been used to compare all formulations and to relate results with the morphology of the blends. Indeed, fully characterization of the different PHBV/TPU blends showed that PHBV was incompatible with TPU. The blends showed an improvement of the toughness fracture, finding a maximum with intermediate TPU contents.
Jennifer González-Ausejo; Estefania Sánchez-Safont; Luis Cabedo; Jose Gamez-Perez. Toughness Enhancement of Commercial Poly (Hydroxybutyrate-co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU). Journal of Multiscale Modelling 2016, 7, 1 .
AMA StyleJennifer González-Ausejo, Estefania Sánchez-Safont, Luis Cabedo, Jose Gamez-Perez. Toughness Enhancement of Commercial Poly (Hydroxybutyrate-co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU). Journal of Multiscale Modelling. 2016; 7 (4):1.
Chicago/Turabian StyleJennifer González-Ausejo; Estefania Sánchez-Safont; Luis Cabedo; Jose Gamez-Perez. 2016. "Toughness Enhancement of Commercial Poly (Hydroxybutyrate-co-Valerate) (PHBV) by Blending with a Thermoplastic Polyurethane (TPU)." Journal of Multiscale Modelling 7, no. 4: 1.
Novel biodegradable composites based on poly(3-hydroxybutirate-co-3-hydroxyvalerate) (PHBV) and different contents of purifi ed alpha-cellulose fibers (3, 10, 25 and 45%) were prepared by melt blending and characterized. The composites were characterized by scanning electron microscopy (SEM), wide-angle X-ray scattering (WAXS) experiments, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanic analysis (DMA) and Shore D hardness measurements. Disintegrability under composting conditions was studied according to the ISO 20200 standard. Morphological results showed that high dispersion of the fibers was achieved during mixing. Good adhesion on the fiber-matrix interface was also detected by SEM. The addition of low and medium cellulose contents did not result in lower thermal resistance with respect to the neat PHBV. A reinforcing effect of the cellulose fibers was detected in all samples, this effect being more pronounced at high temperatures. The composting results show that the addition of the fi bers did not affect the disintegrability of the PHBV, and thus compostable "green" low-cost PHBV/cellulose composites can be obtained.
Estefanía Lidón Sánchez-Safont; Jennifer González-Ausejo; Jose Gamez-Perez; José María Lagarón; Luis Cabedo. Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Purified Cellulose Fiber Composites by Melt Blending: Characterization and Degradation in Composting Conditions. Journal of Renewable Materials 2016, 4, 123 -132.
AMA StyleEstefanía Lidón Sánchez-Safont, Jennifer González-Ausejo, Jose Gamez-Perez, José María Lagarón, Luis Cabedo. Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Purified Cellulose Fiber Composites by Melt Blending: Characterization and Degradation in Composting Conditions. Journal of Renewable Materials. 2016; 4 (2):123-132.
Chicago/Turabian StyleEstefanía Lidón Sánchez-Safont; Jennifer González-Ausejo; Jose Gamez-Perez; José María Lagarón; Luis Cabedo. 2016. "Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate)/Purified Cellulose Fiber Composites by Melt Blending: Characterization and Degradation in Composting Conditions." Journal of Renewable Materials 4, no. 2: 123-132.
The modification of Nafion membranes with polyaniline (PAni) has been studied as an alternative for reducing methanol crossover in direct methanol fuel cells (DMFC). The modification has been performed by directly polymerizing the PAni following two different routes: immersion (Naf-S-Y, where S mean surface and Y the number of hours exposition) and crossover (Naf-C-Y, where C means crossover). The former consist of exposing the membranes to a reactive solution containing the aniline, oxidant and catalyst; while in the latter the aniline and a solution with the oxidant and the catalyst are in different chambers separated by the membrane, thus forcing them to react inside it. The effect of the modification mechanism and the reaction times has been studied. The resulting membranes were extensively characterized by means of Fourier Transform Infrared (FTIR), ionic exchange capacity (IEC), water uptake (WU), methanol permeability and single direct methanol fuel cell performance. Chemical characterization revealed that the oxidation state of the polyaniline was in all cases emeraldine and the amount of PAni for an equivalent exposure time was bigger for the crossover route. The crossover route has proven to be more effective in decreasing the apparent methanol permeability of Nafion modified membranes up to 48% for the crossover sample with higher modification time when the polymerization is due inside the membrane such is the case of the composite Naf-C-Y membranes. The Direct Methanol Fuel Cells performances of membrane-electrode assemblies prepared with pristine Nafion and Nafion-PAni membranes were tested at 40, 60 and 80°C under 2 M methanol concentration. The results are compared with those found for Nafion pristine membranes which power densities were 90, 65, 60 and 50 mW/cm2 at 80°C for Nafion, Naf-S-1, Naf-S-5 and Naf-C-2, membranes respectively.
J. González-Ausejo; Luis Cabedo; Jose Gamez-Perez; S. Molla; E. Gimenez; Vicente Compañ. Modification of Nafion Membranes with Polyaniline to Reduce Methanol Permeability. Journal of The Electrochemical Society 2015, 162, E325 -E333.
AMA StyleJ. González-Ausejo, Luis Cabedo, Jose Gamez-Perez, S. Molla, E. Gimenez, Vicente Compañ. Modification of Nafion Membranes with Polyaniline to Reduce Methanol Permeability. Journal of The Electrochemical Society. 2015; 162 (14):E325-E333.
Chicago/Turabian StyleJ. González-Ausejo; Luis Cabedo; Jose Gamez-Perez; S. Molla; E. Gimenez; Vicente Compañ. 2015. "Modification of Nafion Membranes with Polyaniline to Reduce Methanol Permeability." Journal of The Electrochemical Society 162, no. 14: E325-E333.
The main goal of this work is describing the experience in using Project Based Learning (PBL) methodology in Materials Science courses in several Engineering degrees. The courses were taught simultaneously in four different Spanish universities. In addition, the impact of this proposal on the acquisition of transversal skills through the perceptions of students and teachers is assessed. In order to do so, voices of over 54 students and 5 lecturers involved in the work have been gathered and studied descriptively. Discussion groups and self-reports have been collected and subsequently analysed. The analysis of the data collected by these two instruments has been coded and categorized into general dimensions. The results show how, through the PBL, self-learning is encouraged and the development of transversal skills such as teamwork are enhanced. Meanwhile, the lecturers consider PBL an appropriate methodology for Materials Science courses; however its implementation requires a higher work load. The faculty acknowledged PBL as a very interesting tool to work and evaluate transversal competences. Hence, the PBL methodology stands as one of the most effective methods that meet the demands of the 21st century and enables students to acquire not only content based knowledge, but also other abilities.
M. Lidón Moliner; Teresa Guraya; Pablo Lopez-Crespo; Marta Royo; Jose Gamez-Perez; Mercé Segarra; Luis Cabedo. Acquisition of transversal skills through PBL: a study of the perceptions of the students and teachers in materials science courses in engineering. Multidisciplinary Journal for Education, Social and Technological Sciences 2015, 2, 121 -138.
AMA StyleM. Lidón Moliner, Teresa Guraya, Pablo Lopez-Crespo, Marta Royo, Jose Gamez-Perez, Mercé Segarra, Luis Cabedo. Acquisition of transversal skills through PBL: a study of the perceptions of the students and teachers in materials science courses in engineering. Multidisciplinary Journal for Education, Social and Technological Sciences. 2015; 2 (2):121-138.
Chicago/Turabian StyleM. Lidón Moliner; Teresa Guraya; Pablo Lopez-Crespo; Marta Royo; Jose Gamez-Perez; Mercé Segarra; Luis Cabedo. 2015. "Acquisition of transversal skills through PBL: a study of the perceptions of the students and teachers in materials science courses in engineering." Multidisciplinary Journal for Education, Social and Technological Sciences 2, no. 2: 121-138.
Luis Cabedo; Teresa Guraya; Pablo López-Crespo; Marta Royo; Jose Gámez-Pérez; Mercè Segarra; Lidón Moliner. A Project Based Learning interuniversity experience in materials science. HEAd'15. Conference on Higher Education Advances 2015, 280 -287.
AMA StyleLuis Cabedo, Teresa Guraya, Pablo López-Crespo, Marta Royo, Jose Gámez-Pérez, Mercè Segarra, Lidón Moliner. A Project Based Learning interuniversity experience in materials science. HEAd'15. Conference on Higher Education Advances. 2015; ():280-287.
Chicago/Turabian StyleLuis Cabedo; Teresa Guraya; Pablo López-Crespo; Marta Royo; Jose Gámez-Pérez; Mercè Segarra; Lidón Moliner. 2015. "A Project Based Learning interuniversity experience in materials science." HEAd'15. Conference on Higher Education Advances , no. : 280-287.
The influence of the incorporation of tris(nonylphenyl) phosphite (TNPP) as a chain extender on the morphology and thermal stability of poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV)/clay nanocomposites obtained by melt mixing has been studied. Two different clays have been used: a laminar organomodified montmorillonite (Cloisite® 30B) and a tubular unmodified halloysite (HNT). The morphology of the so‐obtained nanocomposites has been assessed by transmission electron microscopy, scanning electron microscopy, and wide angle X‐ray diffraction, showing a partially exfoliated structure for PHBV/Cloisite® 30B nanocomposites, as well as a good dispersion of the HNT in the PHBV matrix. The crystallinity of the resulting nanocomposites, determined by DSC, does not change when clays or TNPP are added. An increase in the onset temperature of thermal degradation of PHBV has been obtained with the addition of TNPP, as determined by TGA. With regard to the effect of the nanoclays on the thermal stability of PHBV, the onset temperature of the PHBV/HNT nanocomposites is higher than that of the pure PHBV, while this trend is not observed for the nanocomposites containing Cloisite® 30B. The addition of TNPP to the PHBV/Cloisite® 30B nanocomposites resulted in an improved thermal stability; however, for the HNT nanocomposites, the TNPP does not seem to have a significant effect. For all studied systems, it was shown that the variation of mechanical properties of the nanocomposites is due to the reinforcing effect of the nanoclays on the PHBV matrix. In the case of TNPP, it is due to the increased molecular weight and formation of a long‐chain branching structure. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42390.
Jennifer González-Ausejo; Estefania Sánchez‐Safont; Jose Gámez-Pérez; Luis Cabedo. On the use of tris(nonylphenyl) phosphite as a chain extender in melt-blended poly(hydroxybutyrate-co-hydroxyvalerate)/clay nanocomposites: Morphology, thermal stability, and mechanical properties. Journal of Polymer Science 2015, 133, 1 .
AMA StyleJennifer González-Ausejo, Estefania Sánchez‐Safont, Jose Gámez-Pérez, Luis Cabedo. On the use of tris(nonylphenyl) phosphite as a chain extender in melt-blended poly(hydroxybutyrate-co-hydroxyvalerate)/clay nanocomposites: Morphology, thermal stability, and mechanical properties. Journal of Polymer Science. 2015; 133 (2):1.
Chicago/Turabian StyleJennifer González-Ausejo; Estefania Sánchez‐Safont; Jose Gámez-Pérez; Luis Cabedo. 2015. "On the use of tris(nonylphenyl) phosphite as a chain extender in melt-blended poly(hydroxybutyrate-co-hydroxyvalerate)/clay nanocomposites: Morphology, thermal stability, and mechanical properties." Journal of Polymer Science 133, no. 2: 1.
The addition of organo-modified silica particles (OSP) to organic monolayer coatings has been investi-gated as an alternative to the use of primers or surface pretreatments in galvanised steel substrates. Acommercial additive consisting of trifunctional organosilane (alkyl-triethoxysilane) grafted on silica par-ticles was directly incorporated at different concentrations (1, 2.5, 3.5 and 4.5 wt%) as an integral additivein a polyester powder coating. The OSP were characterised physicochemically by means of FTIR and TGA,and the coating formulated by DSC. The anticorrosive properties of the systems were evaluated by meansof electrochemical impedance spectroscopy (EIS), showing improvements with all the formulations con-taining the OSP, especially in the coating with 2.5% OSP. In order to explain this behaviour, morphological(using SEM) and adhesion studies were done. The formation of agglomerates in the powder coatings wasdetected when the concentration was over 2.5%. There was an improvement in the adhesion of the coat-ing to the substrate for all the samples containing the OSP but especially for that containing 2.5%. Theimpact resistance was increased too, especially in the formulations with 2.5% and 3.5%.This work has been financially supported by the Spanish Ministry of the Economy and Competitiveness and the ERDF (Project IPT-020000-2010-1).Publicad
M. Puig; Luis Cabedo; J.J. Gracenea; Antonia Jiménez-Morales; Jose Gamez-Perez; J.J. Suay. Adhesion enhancement of powder coatings on galvanised steel by addition of organo-modified silica particles. Progress in Organic Coatings 2014, 77, 1309 -1315.
AMA StyleM. Puig, Luis Cabedo, J.J. Gracenea, Antonia Jiménez-Morales, Jose Gamez-Perez, J.J. Suay. Adhesion enhancement of powder coatings on galvanised steel by addition of organo-modified silica particles. Progress in Organic Coatings. 2014; 77 (8):1309-1315.
Chicago/Turabian StyleM. Puig; Luis Cabedo; J.J. Gracenea; Antonia Jiménez-Morales; Jose Gamez-Perez; J.J. Suay. 2014. "Adhesion enhancement of powder coatings on galvanised steel by addition of organo-modified silica particles." Progress in Organic Coatings 77, no. 8: 1309-1315.