Halloysite and Laponite Hybrid Pigments Synthesis with Copper Chlorophyll

Sustainable and green materials have been studied in dye and pigment productions to reduce their environment impacts from being produced and applied. Although natural dyes are an excellent choice to move from agrowaste, some improvements must be made before they are applied given their poor fastness. One way of improving natural dye properties is their adsorption into nanoclay structures to give hybrid pigments. This work used tubular halloysite and laminar laponite to adsorb and stabilize natural copper chlorophyll. With a statistical design of experiments, we observed interactions between synthesis factors, such as pH, ionic strength, and surfactant or silane modification. Cool hybrid pigments with high TSR (%) values and a wide color range were obtained by using dispersions with only distilled water at room temperature. Successful chlorophyll adsorption on both nanoclay surfaces took place by XRD and DTA analyses. The maximum natural dye absorption for both nanoclay types took place under acid conditions, pH 3–4, and in the presence of mordant. The TSR (%) improved by the silane pH interaction, and halloysite hybrid pigments obtained higher TSR values than the laponite ones. Finally, a wide chromatic green color range was obtained with the surfactant modification in both nanoclays, and the color fastening was also improved in the hybrid pigments application. The samples generated with 10% of hybrid pigments from both nanoclays and an Epoxy bioresin, show higher colorfastness than the sample with the natural chlorophyll, due to the nanoclays–dye interaction and protection.This research was funded by Spanish Ministry of Economy and Competitiveness (project RTI2018-096000-B-100)

On how the abandonment of traditional forest management practices could reduce saproxylic diversity in the Mediterranean Region

Forests of the Mediterranean Basin provide a wide range of provisioning and regulating services that are currently jeopardised by land-use change. Although many ecosystem services are mediated by insects, most of the studies that have focused on how to enhance diversity in traditionally managed forests are about plants and vertebrates. Quercus pyrenaica woodlands of the Western Iberian Peninsula constitute a scenario in which traditional human practices (i.e., extensive livestock grazing, pollarding, firewood, forest thinning, etc.), and their progressive abandonment, have generated differences in landscape that affect habitat and microhabitat structures. We used saproxylic beetles (deadwood-dependent species) as biological indicators because they are the most diverse taxa and provide important ecosystem services related to deadwood decomposition, forest pest control and pollination. We modelled the response of two taxonomic (species richness and abundance), one ecological (species diversity of order 1) and two functional (functional richness and redundancy) diversity metrics to the environmental variables that result from traditional management or its abandonment at habitat and microhabitat levels. We included 16 explanatory variables related to forest structure, tree microhabitats and abiotic factors, which were grouped into eight principal components. Linear regression was the best fitting model for data. The resulting models were used to perform diversity predictions in different scenarios. We found that abandonment of some traditional forest management activities in the Mediterranean Region reduced taxonomic saproxylic beetle diversity, which may be further aggravated by climate change. We suggest minimal management actions to improve taxonomic and ecological saproxylic beetle diversity related to habitat and tree management (i.e., maintenance of >20% scrub coverage, >20 m3/ha of deadwood on soil and >20 hollow trees/ha). However, actions that boost saproxylic biodiversity do not ensure the community’s higher functional resilience. We should also promote tree microhabitat diversity to reduce the vulnerability of saproxylic beetle functions to environmental changes.Financial support was provided by the Ministerio de Economía y Competitividad (Projects CGL2016-78181-R) and Ministerio de Ciencia e Innovación (PID2020-115140RB-I00) granted to EM and EG. This research forms part of Sandra Martínez Pérez’s PhD studies granted by ’Ministerio de Economía, Industria y Competitividad’ (BES-2017-080278)

Strategies for continuous improvement in the master's degree in "Colour Technology for the automotive sector" based on feedback from graduates

[ES] The first edition of the Master's Degree in "Color Technology for the Automotive Sector" was held during the last academic year. The academic results in terms of qualifications, achievement and learning were good. In spite of the good sensations, there are aspects to be improved, both in methodology and the development of the subjects, timing of the contents, organization or communication channels. Following this line, the Academic, agreed on a plan of continuous improvement based on the feedback provided by the graduate surveys. A specific survey was carried out to gather their specific experience of the course in order to be able to modify the general strategy of the master's degree at the teaching and organisational level. The objectives were to adapt the teaching methodology to facilitate a more reflexive, participative and autonomous learning with a high degree of involvement and motivation of the students, to improve the academic results in terms of learning and satisfaction, to simplify and improve the logistic management of the course, etc. Thus, the survey included questions relating to the usefulness of the master's degree, methodology, organisation and planning of teaching, as well as a final question relating to the overall satisfaction of the course. A short survey was chosen with only 10 questions that the student rated from 1 to 5 on a scale from "strongly disagree" to "strongly agree". From the analysis of the responses, some important weaknesses were detected, such as the lack of content developed in video format, and the slowness of feedback on the results obtained in the proposed tasks. Based on these results, it was proposed an improvement plan that included the incorporation of videos to teaching materials, flexibility in the deadlines for activities, and the periodic monitoring of student learning and concerns through "Adobe Connect".Perales, E.; Micó-Vicent, B.; Viqueira, V.; Huraibat, K.; Martínez-Verdú, FM. (2019). Strategies for continuous improvement in the master's degree in "Colour Technology for the automotive sector" based on feedback from graduates. En INNODOCT/18. International Conference on Innovation, Documentation and Education. Editorial Universitat Politècnica de València. 165-174. https://doi.org/10.4995/INN2018.2018.8846OCS16517

Synthesis of pillared clays from metallic salts as pigments for thermosolar absorptive coatings

[EN] A general procedure for developing stable solar absorptive coatings at both high temperature and a high solar radiation concentration is presented. In order to generally improve thermal efficiency, a coating with high solar absorptance is applied all over the surface of receiver tubes that is subjected to extreme working conditions. Consequently, a durable coating with high absorptivity for sunlight is needed. An alternative paint formulation research and development line to Pyromark-2500, the paint currently used in many commercial solar thermal power plants (CSP) is proposed. Pigment synthesis is developed by intercalating metallic salts into laminar or tubular clay structures. Metallic pxides, which provide paint with its color properties, are obtained by a calcination process. Addition of silane or surfactants during the pigment synthesis is also optimized. Once dried and ground to a precise size, pigments are mixed with a commercial binder and applied to a metallic substrate to study their properties. Thermal stability to high temperature is studied with different tests. The results showed that laminar structure was preferred to intercalate larger amounts of metallic salt into the clay structure, and no significant differences were found when using silane or surfactant modifiers. Although the highest absorptivity value was 85% after 24 h at 600 degrees C, samples presented very good adherence to the metallic substrate. Addition of a small quantity of commercial black pigment to the paint composition could improve the absorptivity and maintain the excellent adhesion shown. Furthermore, montmorillonite clay, modified with a surfactant before adding metallic salt, and without silane, resulted in a black pigment in a powder form. This pillared clay could be used in future paint formulations. (C) 2017 Elsevier Ltd. All rights reserved.The research that has led to these results was funded by Abengoa Solar New Technologies S.A. by a private contract with the Colour and Vision Group of the University of Alicante.Micó Vicent, B.; López-Herraiz, M.; Bello, A.; Martínez, N.; Martinez-Verdu, FM. (2017). Synthesis of pillared clays from metallic salts as pigments for thermosolar absorptive coatings. Solar Energy. 155:314-322. doi:10.1016/j.solener.2017.06.034S31432215

Using Laminar Nanoclays for Phycocyanin and Phycoerythrin Stabilization as New Natural Hybrid Pigments from Microalgae Extraction

C-Phycocyanin (PC) and B-phycoerythrin (PE) are light-harvesting water-soluble phycobiliproteins from microalgae that belong mainly to the cyanobaceria and rhodhophytes families. Different methods have been developed for PC and PE extraction and purification from microalgae, and offer a high potential for their use as additives in sectors such as food and cosmetics. However, the main limitations of using these dyes are the sensitivity of their environmental factors, such as light fastness, temperature, and pH. We successfully employed safe lamellar nanoclays such as montmorillonite (M) and Laponite (L) for phycobiliproteins stabilization, as we did before with other natural dyes. We obtained a wide color gamut from blues to pink by combining four different factors under synthesis conditions: three dye concentrations; two laminar nanoclay sizes; a two nanoclay surface modifiers combination with cetylpyridinium bromide (CPB) and a coupling agent (3-Aminopropyl) triethoxysilane. The experimental conditions were defined according to a multilevel factorial design of experiment (DOE) to study the factors interacting in the final hybrid pigment characteristics. In both M and L, the d001 distance (nm) increased due to PC and PE adsorption. The best conditions to increase the basal space depend on the nanoclay structure, and it is better to use the surfactant for M, and silane modification for L. In addition, optical and thermal PE and PC properties significantly improved. We show the optimal synthesis conditions to increase PC and PE adsorption using the high dye concentration, with surfactant and silane depending on the nanoclay. The hybrid pigments from these phycobiliproteins offer the opportunity to perform several industrial applications, including in polymer additives, cosmetics, and packaging.This research was funded by Spanish Ministry of Economy and Competitiveness (Project RTI2018-096000-B-100)

Optimum Multilayer-Graphene-Montmorillonite Composites From Sugar for Thermosolar Coatings Formulations

Solar thermal coatings are designed to achieve the highest incident solar flux into the receiver of a tower solar plant. These materials are subjected to extreme working conditions of temperature and solar concentrated radiation. Much effort is being made to develop a durable and high absorptive coating that can provide an excellent solar to heat conversion efficiency. Complex deposition techniques (PVD, CVD, electrodeposition, etc.) are developed and tested to achieve solar selectivity. High solar absorptance paints are an alternative technique, that is, easy to apply and implement in the field. In paint, pigments are the compound that provides high absorptance values, whose stability impacts the durability of optical properties. The search for new selective solar pigments for solar receivers is a promising route to improve the efficiency of this technology. In this work, novel nanocomposites were synthesized from low-cost organic materials such as table sugar. Promising results were obtained when intercalated and calcined in the laminar structure of montmorillonite, a type of smectite clay. The pigments were tested in a paint format on metallic coupons at different temperatures to obtain absorptivities above 96% of absorptance after 24 h at 700  °C. Further experiments are still needed to obtain optimum conditions to maximize the coating's absorptivity and durability at high temperature.Abengoa Solar S.A

Maximization of FDM-3D-Objects Gonio-Appearance Effects Using PLA and ABS Filaments and Combining Several Printing Parameters: "A Case Study"

[EN] In order to consider 3D objects from suitable Fused Deposition Modelling (FDM) printers as prototypes for the automotive sector, this sample must be able to reproduce textural effects (sparkle or graininess) or metallic or gonio-appearance to reinforce the attractive appeal of these materials. This study worked with two different commercial filaments: grey metallic PLA (poly(lactic acid)) and ABS (acrylonitrile-butadiene-styrene copolymer) with diffractive pigments. For both materials, a statistical design of experiments (DoE) was carried out to find the printing parameters effect on the final 3D-objects gonio-appearance. The selected printing parameters were printing speed (2 levels), layer height (2 levels) and sample thickness (3 levels). Twelve smooth square objects were printed from each material. The ABS-diffractive filaments achieved the most significant flop and higher sparkle values than metallic PLA. Graininess was high when working with PLA filaments instead of ABS. Layer height was the most significant parameter to maximize PLA objects' flop or sparkle effects. The best result was found when printing at 0.1 mm. For the ABS samples, the stronger flop and sparkle effects were achieved with the 50 mm/s printing speed, the 0.1 mm layer height and the lowest thickness level. This study shows the methodology to study the printing parameters effects and interactions to maximize the FDM-3D-objects gonio-appearance.This research was funded by the Spanish Agencia Estatal de Investigacion (AEI), the European Union (FEDER funds) (Contract MAT2016-77742-C2-1-P) and the Spanish Ministry of Economy and Competitiveness (project DPI2015-65814-R).Micó-Vicent, B.; Perales Romero, E.; Huraibat, K.; Martínez-Verdú, F.; Viqueira, V. (2019). Maximization of FDM-3D-Objects Gonio-Appearance Effects Using PLA and ABS Filaments and Combining Several Printing Parameters: "A Case Study". Materials. 12(9). https://doi.org/10.3390/ma12091423S129Guo, N., & Leu, M. C. (2013). Additive manufacturing: technology, applications and research needs. Frontiers of Mechanical Engineering, 8(3), 215-243. doi:10.1007/s11465-013-0248-8Sood, A. K., Ohdar, R. K., & Mahapatra, S. S. (2010). Parametric appraisal of mechanical property of fused deposition modelling processed parts. Materials & Design, 31(1), 287-295. doi:10.1016/j.matdes.2009.06.016Pandey, P. M., Venkata Reddy, N., & Dhande, S. G. (2003). Improvement of surface finish by staircase machining in fused deposition modeling. Journal of Materials Processing Technology, 132(1-3), 323-331. doi:10.1016/s0924-0136(02)00953-6Chohan, J. S., Singh, R., Boparai, K. S., Penna, R., & Fraternali, F. (2017). Dimensional accuracy analysis of coupled fused deposition modeling and vapour smoothing operations for biomedical applications. Composites Part B: Engineering, 117, 138-149. doi:10.1016/j.compositesb.2017.02.045Parandoush, P., & Lin, D. (2017). A review on additive manufacturing of polymer-fiber composites. Composite Structures, 182, 36-53. doi:10.1016/j.compstruct.2017.08.088Project focuses on automotive 3D printing. (2017). Metal Powder Report, 72(6), 441-442. doi:10.1016/j.mprp.2017.10.002Rodríguez-Panes, A., Claver, J., & Camacho, A. (2018). The Influence of Manufacturing Parameters on the Mechanical Behaviour of PLA and ABS Pieces Manufactured by FDM: A Comparative Analysis. Materials, 11(8), 1333. doi:10.3390/ma11081333Topp, K., Haase, H., Degen, C., Illing, G., & Mahltig, B. (2014). Coatings with metallic effect pigments for antimicrobial and conductive coating of textiles with electromagnetic shielding properties. Journal of Coatings Technology and Research, 11(6), 943-957. doi:10.1007/s11998-014-9605-8Debeljak, M., Hladnik, A., Černe, L., & Gregor-Svetec, D. (2012). Use of effect pigments for quality enhancement of offset printed specialty papers. Color Research & Application, 38(3), 168-176. doi:10.1002/col.20753Ferrero, A., Perales, E., Rabal, A. M., Campos, J., Martínez-Verdú, F. M., Chorro, E., & Pons, A. (2014). Color representation and interpretation of special effect coatings. Journal of the Optical Society of America A, 31(2), 436. doi:10.1364/josaa.31.000436McCamy, C. S. (1996). Observation and measurement of the appearance of metallic materials. Part I. Macro appearance. Color Research & Application, 21(4), 292-304. doi:10.1002/(sici)1520-6378(199608)21:43.0.co;2-lMcCamy, C. S. (1998). Observation and measurement of the appearance of metallic materials. Part II. Micro appearance. Color Research & Application, 23(6), 362-373. doi:10.1002/(sici)1520-6378(199812)23:63.0.co;2-5Kirchner, E., van der Lans, I., Perales, E., Martínez-Verdú, F., Campos, J., & Ferrero, A. (2015). Visibility of sparkle in metallic paints. Journal of the Optical Society of America A, 32(5), 921. doi:10.1364/josaa.32.000921Rathee, S., Srivastava, M., Maheshwari, S., & Siddiquee, A. N. (2017). Effect of varying spatial orientations on build time requirements for FDM process: A case study. Defence Technology, 13(2), 92-100. doi:10.1016/j.dt.2016.11.006Mohamed, O. A., Masood, S. H., & Bhowmik, J. L. (2016). Optimisation of Dynamic Mechanical Thermal Properties of PC–ABS Parts Manufactured by FDM Process Using IV Optimal Design. Reference Module in Materials Science and Materials Engineering. doi:10.1016/b978-0-12-803581-8.04025-xSingh, R., Singh, S., Singh, I. P., Fabbrocino, F., & Fraternali, F. (2017). Investigation for surface finish improvement of FDM parts by vapor smoothing process. Composites Part B: Engineering, 111, 228-234. doi:10.1016/j.compositesb.2016.11.062Mohamed, O. A., Masood, S. H., & Bhowmik, J. L. (2017). Experimental investigation of time-dependent mechanical properties of PC-ABS prototypes processed by FDM additive manufacturing process. Materials Letters, 193, 58-62. doi:10.1016/j.matlet.2017.01.104Chorro, E., Perales, E., Burgos, F. J., Gómez, O., Vilaseca, M., Viqueira, V., … Martínez-Verdú, F. M. (2015). The minimum number of measurements for colour, sparkle, and graininess characterisation in gonio-apparent panels. Coloration Technology, 131(4), 303-309. doi:10.1111/cote.12157Pandey, P. M., Thrimurthulu, K., & Reddy *, N. V. (2004). Optimal part deposition orientation in FDM by using a multicriteria genetic algorithm. International Journal of Production Research, 42(19), 4069-4089. doi:10.1080/00207540410001708470Alsoufi, M. S., & Elsayed, A. E. (2018). Surface Roughness Quality and Dimensional Accuracy—A Comprehensive Analysis of 100% Infill Printed Parts Fabricated by a Personal/Desktop Cost-Effective FDM 3D Printer. Materials Sciences and Applications, 09(01), 11-40. doi:10.4236/msa.2018.91002Kirchner, E. (2009). Film shrinkage and flake orientation. Progress in Organic Coatings, 65(3), 333-336. doi:10.1016/j.porgcoat.2009.01.006Ferrero, A., Bernad, B., Campos, J., Perales, E., Velázquez, J. L., & Martínez-Verdú, F. M. (2016). Color characterization of coatings with diffraction pigments. Journal of the Optical Society of America A, 33(10), 1978. doi:10.1364/josaa.33.00197

Diseño de guías docentes con una metodología híbrida para la mejora del aprendizaje personalizado

El aprendizaje personalizado considera la existencia de diferentes perfiles de alumno en cuanto a su estilo de aprendizaje y a su estilo de comportamiento. Teniendo en cuenta estos dos aspectos, en este trabajo se desarrolla una metodología docente específica para una titulación concreta: el postgrado propio en “Tecnología del color para el sector de automoción” ofertado por la Universidad de Alicante. Las guías docentes y el diseño de los contenidos educativos de este postgrado han sido elaborados teniendo en cuenta las competencias y objetivos demandados por el sector industrial. La metodología propuesta emplea la plataforma Moodle para aprovechar las posibilidades del b-learning, adaptando los contenidos a los diferentes estilos de aprendizaje, perfiles de estudiantes, competencias iniciales (física, química, ingeniería, etc.), disponibilidad y grado de implicación. Esta metodología pretende maximizar el rendimiento académico del alumno, buscando la máxima motivación al adaptar las tareas propuestas a la tipología de cada estudiante. Para ello, se diseñan actividades individuales y grupales adaptadas para cada perfil, teniendo en cuenta los diferentes estilos de aprendizaje definidos por D. Kolb

Diseño de una metodología docente mediante el aprendizaje personalizado

Este trabajo resume el desarrollo de la metodología docente propuesta dentro del postgrado propio en Tecnología del color para el sector de automoción. Esta metodología está basada en b-learning usando para ello la plataforma Moodle que pretende seguir diferentes estilos de aprendizaje, y perfiles de estudiantes y sus competencias iniciales (física, química, ingeniería, etc.) y disponibilidad (trabajador activo, etc.). El objetivo de esta metodología es obtener el máximo rendimiento y satisfacción del alumnado y para ello, se han diseñado actividades individuales y grupales adaptadas para cada perfil, teniendo en cuenta diferentes estilos de aprendizaje definidos por Kolb. Este modelo teórico tiene en cuenta diferentes aspectos o capacidades básicas: experiencia concreta (EC, alumno activo), observación reflexiva (OR, alumno reflexivo), conceptualización abstracta (CA, alumno teorizador) y experimentación activa (EA, alumno pragmático), que combinándolos dan lugar a diferentes estilos de aprendizaje, siempre con el fin de conseguir un papel activo, satisfactorio a nivel dual (docente-discente) y de rendimiento en el proceso de aprendizaje

Anthocyanin Hybrid Nanopigments from Pomegranate Waste: Colour, Thermomechanical Stability and Environmental Impact of Polyester-Based Bionanocomposites

In the present work, anthocyanin (ACN) hybrid nanopigments were synthetized by using a natural pomegranate dye (PD) and calcined hydrotalcite (HT) and montmorillonite (MMT) nanoclays. A wide colour gamut was obtained with MMT-based nanopigments ranging from reddish to bluish hues caused by structural transformations of ACNs at different pH values. However, a buffer effect was observed with HT obtaining samples a similar final colour regardless of the synthesis conditions. Nanopigments added with a biomordant extracted from pomegranate peels showed a different colour compared to the incorporation of a commercial mordant due to the intrinsic colouring properties of the pomegranate bioadditive. The developed nanopigments were incorporated at 7 wt% loading to produce novel polyester-based bionanocomposites which were characterized in terms of thermal, mechanical and colour properties. The encapsulation of PD into the nanoclays improved its thermal stability, in particular for MMT-based nanopigments. The pH changes observed during the nanofillers synthesis affected the final colour of the MMT-based nanocomposites, inducing a general increase in ∆E* and a decrease in gloss values. Slight improvements were obtained in terms of elastic modulus for MMT-based polymer samples confirming the applicability of the developed bionanocomposites as colouring and reinforcement materials. A very similar environmental profile was obtained for MMT and HT-based nanofillers showing MMT-based nanopigments a slightly better general behaviour. The results of the LCA study evidenced the suitability of the processes used in this work to the circular bioeconomy approach through sustainable food waste management and the production of bioplastics using waste substrates.This project has received funding from the Bio Based Industries Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 745578