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A method consisting of the alkaline hydrolysis of tomato pomace by-products has been optimized to obtain a mixture of unsaturated and polyhydroxylated fatty acids as well as a non-hydrolysable secondary residue. Reaction rates and the activation energy of the hydrolysis were calculated to reduce costs associated with chemicals and energy consumption. Lipid and non-hydrolysable fractions were chemically (infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS)) and thermally (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) characterized. In addition, the fatty acid mixture was used to produce cutin-based polyesters. Freestanding films were prepared by non-catalyzed melt-polycondensation and characterized by Attenuated Total Reflected-Fourier Transform Infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (NMR), DSC, TGA, Water Contact Angles (WCA), and tensile tests. These bio-based polymers were hydrophobic, insoluble, infusible, and thermally stable, their physical properties being tunable by controlling the presence of unsaturated fatty acids and oxygen in the reaction. The participation of an oxidative crosslinking side reaction is proposed to be responsible for such modifications. ; Andalusian Regional Government P11-TEP-7418 ; Spanish Ministerio de Economía y Competitividad AGL2015-65246-R and AGL2017-83036-R ; Fondo Europeo de Desarrollo Regional (FEDER) AGL2015-65246-R and AGL2017-83036-R

13 páginas.-- 3 figuras.-- 3 tablas.-- 47referencias.-- : The following are available online at http://www.mdpi.com/1996-1944/11/11/2211/s1.__ This article belongs to the Special Issue Biodegradable Polymeric Composites: Development and Industrial Applications ; A method consisting of the alkaline hydrolysis of tomato pomace by-products has been optimized to obtain a mixture of unsaturated and polyhydroxylated fatty acids as well as a nonhydrolysable secondary residue. Reaction rates and the activation energy of the hydrolysis were calculated to reduce costs associated with chemicals and energy consumption. Lipid and nonhydrolysable fractions were chemically (infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS)) and thermally (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) characterized. In addition, the fatty acid mixture was used to produce cutin-based polyesters. Freestanding films were prepared by non-catalyzed melt-polycondensation and characterized by Attenuated Total Reflected-Fourier Transform Infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (NMR), DSC, TGA, Water Contact Angles (WCA), and tensile tests. These bio-based polymers were hydrophobic, insoluble, infusible, and thermally stable, their physical properties being tunable by controlling the presence of unsaturated fatty acids and oxygen in the reaction. The participation of an oxidative crosslinking side reaction is proposed to be responsible for such modifications. ; This research was funded by the Andalusian Regional Government (Junta de Andalucía) under the Motriz Program, project No. P11-TEP-7418 and to the Spanish Ministerio de Economía y Competitividad and Fondo Europeo de Desarrollo Regional (FEDER), projects No. AGL2015-65246-R and AGL2017-83036-R ; Peer reviewed

El conocimiento actual demuestra la expansión de las propuestas de las fachadas receptivas recurriendo a enfoques biomiméticos, investigación de materiales y diseño algorítmico. Este trabajo recoge las tendencias en materiales y tecnologías que contribuyen al control térmico y ambiental de los edificios a favor de la sostenibilidad. Analizamos once propuestas de fachadas e instalaciones, los diseños elegidos cumplen con los siguientes criterios: presentar diferentes estrategias reversibles de transformación del material y/o materiales de base biológica. En obras futuras, pretendemos proponer nuevas soluciones de fachada receptiva para contribuir a la sostenibilidad de los edificios.

La bioinspiración en las estrategias de diseño de la naturaleza alineadas con la fabricación digital, tienen gran relevancia para la resolución de problemas con un enfoque en la aplicación sistemática de información biológica para la emulación de elementos naturales. Actualmente, las posibilidades están dadas por las últimas tecnologías, sistemas de producción y el desarrollo de nuevas estructuras y materiales. Esta investigación explora la investigación de la biología, el uso de la computación paramétrica y la fabricación digital, incluyendo experimentos con materiales sostenibles como dimensiones inseparables del diseño bioinspirado. Las fibras de Agave Sisalana tienen excelentes propiedades de ligereza y resistencia proporcionadas por el patrón estructural de las paredes celulares y sus propiedades materiales. Presentarse como un sistema natural de inspiración biomimética y experimentación de materiales bioinspirados.

Bio-based insulation materials (such as wood or hemp) are emerging as a promising alternative in building envelope applications, aiming at improving in-use energy efficiency. When compared to common insulation materials (rock and glass wool or petrol-based foams) bio-based materials present the advantage of being renewable, with a low embodied energy and CO2 neutral or negative. Moreover, these materials have a distinct hygrothermal performance, as the sorption/desorption of water vapour in their porous structure, in dynamic equilibrium with their surrounding environment, constantly modifies their hygric and thermal properties while causing energy transfers itself. In this paper, the hygrothermal performance of two different bio-based materials in outdoor conditions is evaluated. The first is an innovative light-weight composite made from corn pith and alginate. The second a commercially available wood insulator. The materials are tested alone and as components of external thermal insulation systems (ETICS) and compared to a conventional polystyrene foam. The results show how the sorption process influence the hygrothermal performance of the materials when the surrounding conditions are modified. When subjected to cyclic changes in temperature and relative humidity, the bio-based materials tested show a lower temperature variation than polystyrene. This is in part due to their lower thermal diffusivity, but also to the water absorption and desorption mechanisms occurring within the materials, which were measured by the change in mass of the materials during the tests. The differences in the thermal performance were more noticeable when the insulation materials were tested alone than when these were tested as a part of an ETIC System. ; This work was funded by MINECO (Spain) and AEI/FEDER/UE under the projects BIA2014-52688-R, BIA2017-88401-R and ENE2015-64117-C5-3-R. The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2017 SGR 1758). M.P. would like to thank the Brazilian Education Ministry for the financial support received under the PNPD/Capes fellowship. This article has been possible with the support of the Ministerio de Economía y Competitividad (MINECO) and the Universitat Rovira i Virgili (URV) (FJCI-2016-28789).

El impacto ambiental del sector de la construcción, responsable del 40% del consumo total de energía primaria de la Unión Europea, requiere la reducción tanto de la energía incorporada de los materiales de construcción como de la energía operativa que consume un edificio durante su vida útil. La madera y los residuos agrícolas pueden proporcionar materiales renovables de origen biológico de origen local que ayudan a construir una economía circular y a reducir el impacto ambiental del sector de la construcción.Este artículo muestra un ejemplo de un panel aislante estructural prefabricado, hecho con materiales de base biológica, diseñado para su uso en edificios de energía casi nula.AbstractThe environmental impact of the construction sector - responsible for 40% of the total primary energy consumption of the European Union – requires the reduction of both the embodied energy of building materials as well as operational energy consumed by a building during its lifetime. Timber and agricultural residues can provide locally sourced bio-based renewablematerials that help build a circular economy and reduce the environmental impact of the construction sector. This article shows an example of a prefabricated structural insulating panel, made with bio-based materials, designed for use in nearly-zero energy buildings.

In recent years, the implementation of novel solutions aimed at improving thermal energy storage (TES) capability to both energy technologies and building-integrated systems has gained increasing attention. In particular, the application of phase change materials (PCM) is currently gathering worldwide acknowledgment. In this work, the potential of animal fat as a novel bio-based PCM having transition temperature around the ambient temperature is assessed by means of thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and extensive temperature monitoring. Results from the TGA showed the differential degradation of the main components of the animal fat during the heating phase, where three different decomposition steps could be noticed. The thermal monitoring and the DSC analysis demonstrated the promising thermal performance of the material, which showed an interesting double transition range globally associated to a melting enthalpy of about 28.94 kJ kg􀀀1. The obtained results demonstrate the promising thermophysical properties of the animal fat blend, which can be considered as a low-cost, biocompatible PCM, particularly with potential application in passive building envelope applications for a wide range of temperature boundary conditions. ; Funding The work partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). Acknowledgments Cabeza would like to thank the Catalan Government for the quality accreditation given to her research group (2017 SGR 1537). GREA is a certified agent TECNIO in the category of technology developers from the Government of Catalonia. Authors from University of Perugia thank Fondazione cassa di Risparmio di Perugia for supporting the investigation about biomaterials within the project SOS CITTÁ 2018.0499.026.

The reduction in energy demand for heating and cooling with insulation materials increases the material related environmental impact. Thus, implementing low embodied energy materials may equilibrate this trade-off. Actual trends in passive house postulate bio-based materials as an alternative to conventional ones. Despite that, the implementation of those insulators should be carried out with a deeper analysis due to their hygroscopic properties. The moisture transfer, the associated condensation risk and the energy consumption for seven biobased materials and polyurethane for a building-like cubicle are analysed. The performance is evaluated combining a software application to model the cubicle (EnergyPlus) and a tool to optimize its performance (jEPlus). The novelty of this optimization approach is to include and evaluate the effects of moisture in these insulation materials, taking into account the mass transfer through the different layers and the evaporation of the different materials. This methodology helps optimise the insulation type and thickness verifying the condensation risk, preventing the deterioration of the materials. The total cost of the different solutions is quantified, and the environmental impact is determined using the life cycle assessment methodology. The effect of climate conditions and the envelope configuration, as well as the risk of condensation, are quantified. The results show that cost and environmental impact can be reduced if bio-based materials are used instead of conventional ones, especially in semiarid climates. Condensation risk occurs for large thicknesses and in humid climates. In our case studies, hemp offered the most balanced solution. ; The authors would like to acknowledge financial support from the Spanish Government (CTQ2016-77968-C3-1-P, ENE2015-64117-C5-1-R, ENE2015-64117-C5-3-R, MINECO/FEDER, UE). The research leading to these results has received funding from the European Commission Seventh Framework Programme under grant agreement no. PIRSES-GA-2013-610692 (INNOSTORAGE). This project has received funding the European Union's Horizon 2020 Research and Innovation Program under grant agreement No 657466 (INPATH-TES). This article has been possible with the support of the Ministerio de Economía y Competitividad (MINECO) and the Universitat Rovira i Virgili (URV) (FJCI-2016-28789). Authors would like to acknowledge the Brazilian Government for their support by the CNPq (National Council for Scientific and Technological Development). M.P. would like to thank the Brazilian Education Ministry for the financial support received under the PNPD/Capes fellowship. L.F.C. would like to thank the Catalan Government for the quality accreditation given to her research group GREA (2014 SGR 123).