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The endorsement of functional features such as biocompatibility, mechanical integrity, or electrical conductivity to tissue engineering (TE) scaffolds is essential to stimulate cell adhesion and proliferation. In this study, electrospun nanofibers based on polycaprolactone (PCL) and gelatin (Ge) (ratios 60/40, 50/50, and 40/60), and polyaniline (PAni) particles (0.25, 0.50, and 1.00%wt) were prepared. The time of dissolution in an acid solvent mixture before electrospinning allowed for obtaining nanofibers with controlled features. Changes in the molar mass (Mn from 90·103 to 15·103 g·mol−1), in the crystalline microstructure (Xc from 60 to 25%) and the surface morphology (diameter from 250 to 50 nm) due to the controlled hydrolytic action on PCL were found. In vitro degradability and biocompatibility were favoured as the dissolution time and gelatin percentage increased. The presence of PAni was revealed as non-cytotoxic and promoted a controlled increase of the electrical conductivity, that contributed to in vitro cardiomyocyte proliferation. Cellular centres in the vicinities of PAni microparticles could be identified in the scaffold with the 40/60 PCL/Ge scaffold with PAni (1.00%wt), keeping the macrophages profile unaltered, which may determine the satisfactory resolution of cardiac injury and point out these scaffolds as appropriate candidates for cardiac TE.

[EN] Antimicrobial films of poly (lactic acid) (PLA)/D-limonene/zinc oxide (ZnO)-based bio-nanocomposites were prepared via melt compounding and subsequent thermocompression. D-limonene was incorporated at concentrations of 10 or 20 wt%, and ZnO pure nanoparticles and those organically modified with oleic acid (O-ZnO), with an average diameter of 13.5 nm, were included at concentrations of 3, 5, and 8 wt%. The plasticizing effect of D-Limonene was corroborated by a decrease in the glass transition temperature compared to pure PLA. The presence of ZnO and O-ZnO in the PLA matrix promoted a slight increase in the degree of crystallinity due to its nucleant performance. Although ZnO and O-ZnO induced lower thermal stability and slightly decreased microhardness in the composites, excellent antimicrobial performance was demonstrated. Both ZnO and O-ZnO nanocomposites reached 99.9% of effectiveness for nanoparticles content above 5 wt%, regardless of the source of irradiation, D-limonene concentration, and nanoparticle modification. Therefore, these bio-nanocomposites will allow for future advances in sustainable antimicrobial materials for the medical or food packaging fields., DICYT, Grant/Award Number: Project 022041ZR_POSTDOCT; Fondo Nacional de Desarrollo Cientifico y Tecnologico, Grant/Award Numbers: 1170226, 3200296

This paper shows a particular example to move to a sustainable circular economical process from valorization of rice straw ashes by developing a green synthesis for obtaining a useful sub-product. This strategy can palliate negative effects of the agriculture waste practices on the environment and also the obtained silica reduced nitrate content in waters. It is demonstrated that the silica synthesis developed at lab was scalable more than a hundred times with good results. Adsorption studies of nitrate in standards and real well waters at lab scale and scaling-up provided similar results. Adsorption values near to 15 mg/g for nitrate standards and 8.5 mg/g for well water were obtained until achieving the initial nitrate concentration. Experimental breakthrough curves fitted to Thomas model, which gave similar results for adsorption capacities. The adsorption capacity was checked with that obtained by a commercial resin, providing improved results. The method at large scale was compared with industrial traditional methods and green adsorbents.

[EN] The macromolecular dynamics of dendronized copolymer membranes (PECHs), obtained by chemical modification of poly(epichlorohydrin) with the dendron 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, was investigated. In response to a thermal treatment during membrane preparation, these copolymers show an ability to change their shape, achieve orientation, and slightly crystallize, which was also observed by CP-MAS NMR, XRD, and DSC. The phenomenon was deeply analyzed by dielectric thermal analysis. The dielectric spectra show the influence of several factors such as the number of dendritic side groups, the orientation, their self-assembling dendrons, and the molecular mobility. The dielectric spectra present a sub-Tg dielectric relaxation, labelled as gamma, associated with the mobility of the benzyloxy substituent of the dendritic group. This mobility is not related to the percentage of these lateral chains but is somewhat hindered by the orientation of the dendritic groups. Unlike other less complex polymers, the crystallization was dismantled before the appearance of the glass transition (alpha(Tg)). Only after that, clearing transition (alpha(Clear)) can be observed. The PECHs were flexible and offered a high free volume, despite presenting a high degree of modifications. However, the molecular mobility is not independent in each phase and the self-assembling dendrons can be eventually fine-tuned according to the percentage of grafted groups., This research was funded by the Spanish Ministry of Science, Innovation and Universities, grant POLYDECARBOCELL (ENE2017-86711-C3-1-R, ENE2017-86711-C3-3-R).

[EN] The preparation polyelectrolytes based on crosslinked poly(vinyl alcohol) (PVA) and chitosan (CS) was considered as a feasible alternative to develop highly functionalised, cost-effective and eco-friendly membranes for proton exchange fuel cell technologies. CS/PVA-based membranes were combined with sulfosuccinic acid (SSA) as crosslinking and sulfonating agent, and glycerol (GL) to promote flexibility and favour their manageability. The chemical structure, the thermo-oxidative behaviour, the ethanol uptake, the electric, the proton conductivity, and the performance in direct ethanol fuel cell (DEFC) were assessed. In general, all the CS/PVA-based polyelectrolytes showed a synergetic increase of thermo-oxidative stability, appropriate absorption and diffusion of ethanol and good proton conductivity, suitable for the typical service conditions of fuel cells. The GL in the membranes reacted with SSA, reduced the ethanol absorption, diffusion coefficient and proton conductivity, but acted as a plasticiser that increased the ductile manageability of the polyelectrolytes to be mounted on the membrane-electrode assembly (MEA). Higher presence of CS and higher the proportion of GL in the polyelectrolyte, improved the material performance in the DEFC. In particular, the crosslinked polyelectrolyte 40CS/PVA/SSA/20GLwith a 40 %wt. of CS referred to PVA, and a 20 %wt. of GL referred to CS, showed a suitable behaviour in the DEFC test, with a maximum value of power density of 746 mW·cm-2., The Spanish Ministry of Economy, Industry and Competitiveness is acknowledged for the projects ENE2017-86711-C3-1-R and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is thanked for the pre-doctoral FPU grant for O. Gil-Castell (FPU13/01916)

[EN] The thermal stability and decomposition kinetics of PLA/sisal biocomposites was discussed to evaluate the suitability of their use in energy recovery processes such as pyrolysis and combustion. The influence of the addition of sisal up to 30%wt, the presence of coupling agent, and the atmosphere of operation, i.e. inert or oxidative was discussed by means of multi-rate linear non-isothermal thermogravimetric experiments. All biocomposites showed a mean high heating value of 15 MJ/kg indicating their suitability for energy recovery processes. The thermal requirements of PLA/sisal decomposition were assessed in terms of onset decomposition temperature and apparent activation energy. A minimum of 240 degrees C and 174 kJ mol(-1) in inert environment and 225 degrees C and 190 kJ mol(-1) in oxidative environment ensured the feasibility of the reactions regardless the composition of the PLA/sisal biocomposites. The atmosphere of work lead to a greater amount of residue in case of pyrolysis reactions that would need further treatment whereas an oxidative atmosphere resulted in nearly zero final waste stream. The similar kinetics obtained for all samples regardless the amount of sisal or use of coupling agent eases the operability of energy facilities aimed of turning these biowastes into new fuels., The Spanish Ministry of Economy and Competitiveness and European Regional Development Funds are acknowledged for the projects ENE2014-53734-C2-1-R, ENE2017-86711-C3-1-R (UPOV13-3E-1947). Generalitat Valenciana is thanked for the APOSTD/2014/041 for J.D. Badia. The financial support given by the Prince of Songkla University and KTH Royal Institute of Technology is gratefully acknowledged. Rossella Acerbo and Emanuele Righi are gratefully acknowledged for their activity in the framework of their Bachelor Theses.

Unoriented and oriented membranes based on dendronized polymers and copolymers obtained by chemical modification of poly[2-(aziridin-1-yl) ethanol] (PAZE) with the dendron 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy]benzoate were considered. DSC, XRD, CP-MAS NMR and DETA, contribute to characterize the tendency to crystallize, the molecular mobility of the benzyloxy substituent, the dendritic liquid crystalline group and the clearing transition. The orientation of the mesogenic chain somewhat hindered this molecular motion, especially in the full substituted PAZE. The fragility, free volume and thermal expansion coefficients of these membranes near the glass transition are related to the orientation and the addition of the dendritic groups. PAZE-based membranes combine both order and mobility on a supramolecular and macroscopic level, controlled by the dendritic group and the thermal orientation, and open the possibility of preparing membranes with proper channel mobility that promotes selective ionic transport.

[EN] A set of styrene-ethylene-butylene-styrene triblock copolymer (SEBS) membranes with 10 or 25 wt.% divinyl-benzene (DVB) as a crosslinking agent were prepared and validated. Physicochemical characterization revealed suitable hydrolytic and thermal stability of photo-crosslinked membranes containing 25%wt. DVB and post-sulfonated. These compositions were evaluated in H2/O2 single cells, and electrical and proton conductivities were furtherly assessed. The membranes with the milder post-sulfonation showed greater proton conductivity than those with excessive sulfonation. In terms of electrical conductivity, a universal power law was applied, and the values obtained were low enough for being used as polyelectrolytes. At the analyzed temperatures, the charge transport process follows a long-range pathway or vehicular model. Finally, fuel cell performance revealed the best behavior for the membrane with 25 wt.% DVB, photo-crosslinked during 30 min and mild sulfonated, with a promising power density of 526 mW·cm-2. Overall, the results obtained highlight the promising fuel cell performance of these cost-effective triblock copolymer-based membranes and indicate that higher sulfonation does not necessarily imply better power density., Ministerio de Economía, Industria y Competitividad, Gobierno de España, Grant/Award Number: ENE2017-86711-C3-1-R

[EN] The extended use of polymers from renewable resources such as aliphatic polyesters or polyhydroxyalkanoates boosted the necessity to understand their behaviour in an end-of-life scenario. Although they can be degraded in reasonable shorter times than traditional polymers, understanding the degradation mechanisms under dissimilar conditions will contribute to further developments in this field. This work aimed to study the effect of temperature and substrate in the degradation of polylactide (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) in a simulated laboratory scale to ascertain their contribution, separately or in combination. For this purpose, nine parallel degradation assays were performed by means of the combination of mesophilic (25 °C), thermophilic (58 °C) and hyperthermophilic (80 °C) temperatures with enriched synthetic medium, compost and standardised soil substrates. Although the analysis of the surface morphology, the thermal properties and the thermo-oxidative stability revealed changes as a function of time, the evaluation of the molar mass allowed for a more precise determination of the degradation. In general, chain scission was perceived in all cases as a function of time. The effect of temperature was critical, significantly more important than the effect of the substrate, which showed a less significant contribution, especially in terms of molar mass reduction. While for the PLA, biodegradation at 58 °C and thermal degradation at 80 °C resulted in similar consequences, for the PHBH the hyperthermophilic temperature of 80 °C was the most severe condition, regardless of the substrate. From a technological perspective, it may be highlighted that biodegradation at 58 °C may be the most cost-effective condition due to the lower energy supply required and the valuable contribution of the microorganisms., The authors would like to thank the support of the Spanish Ministry of Science, Innovation and Universities, for the POLYDECARBOCELL project (ENE2017-86711-C3-1-R) and the Chilean Economic Development Agency (CORFO) for the project 13CEI2-21839.

Composite polymer electrolyte membranes were prepared with poly (vinyl alcohol) (PVA). Two different molecular weight (Mw), 67·103 and 130·103 g·mol−1 were selected, cross-linked with sulfosuccinic acid (SSA) and doped graphene oxide (GO). The effects on the membranes obtained from these polymers were characterized in order to evaluate the fuel cell performance. Electron microscopy showed a proper nanoparticle distribution in the polymer matrix. The chemical structure was evaluated by Fourier transform infrared spectroscopy. The absence of a crystalline structure and the enhancement on the thermal stability with the addition of 1% of GO was demonstrated by thermal characterization. Total transference number and protonic conductivity were correlated to the performance of a hydrogen fuel cell. Overall, a power increase in the composite membranes with lower molecular weight was observed. Shorter polymer chains may improve protonic conductivity and consequently the fuel cell performance.

[EN] Composite membranes obtained from Poly(vinyl Alcohol) (PVA) with sulfosuccinic acid (SSA) as crosslinking agent, and two different proportions of graphene oxide (GO), were prepared to be used in Proton Exchange Membrane Fuel Cells (PEMFCs). The superficial micrographs from transmission electron microscopy (TEM) confirmed a good dispersion of GO. Fourier Transform Infrared spectroscopy (FTIR) was used to evaluate the final chemical structure. Differential Scanning Calorimetry (DSC) showed that glass transition and crystalline phase were not present in the cross-linked PVA/SSA/GO composites membranes. Thermogravimetric analysis (TGA) demonstrated that the addition of GO reduced the moisture content and increased the thermal stability of the membranes. The electrical properties of PVA/SSA and PVA/SSA/GO composite membranes and the effect of GO concentration were evaluated by means of dielectric spectra in a broad range of temperatures and frequencies. The dielectric permittivity of these membranes was significantly promoted at low filler concentration due to an interfacial polarization effect. From the analysis of the dielectric relaxation spectrum, it can be deduced that the origin of the associated molecular movements is intramolecular and occurs in the working range of the PMEFC. In addition, the direct current conductivity, the protonic conductivity, and the polarization currents were correlated to the power produced in a hydrogen monocell. It was observed that low and no high GO concentrations of filler in PVA/SSA composite membranes enhanced their performance. The systematic characterization procedure based on the study of dielectric spectra and conductivity allowed to establish a potential approach to control the addition of GO in the design of other composite membranes for PEMFC with improved properties., The authors would like to thank Dr. Roberto Teruel Juanes and Dr. Victor Saenz de Juano for their advice in the treatment of results. The authors are also thankful to Generalitat Valenciana and the European Social Fund for the Santiago Grisolia scholarship, GRISOLIA/2013/031, and the Spanish Ministry of Science and Innovation for the concession of Research Project ENE2014-53734-C2-1-R.

[EN] Monitoring and understanding the in vitro behaviour of polyester based scaffolds both comprising the study of the hydrolytic degradation and the cell seeding viability is essential to ensure the desired functionality, according to a given biomedical purpose. As a model case to compare the performance of techniques to monitor the in vitro behaviour, poly(lactide-co-glycolide) (PLGA) scaffolds were chosen. The in vitro hydrolytic degradation of PLGA scaffolds was carried out in water and phosphate buffered saline (PBS). The evolution of the mass loss, the molar mass, the thermal properties and the surface morphology were monitored. The hydrolytic degradation media was correspondingly evaluated by means of the study of the pH, the amount of acid released and the conductivity. In addition, the in vitro biocompatibility regarding the cell culture viability was studied under physiological conditions. The cellular adhesion, cellular ability to proliferate on the scaffold, the scaffold inflammatory profile and the effect of the scaffold degradation compounds on the cells were assessed. A comparative analysis of the exploited techniques in terms of promptness of identification, depth of knowledge, simplicity of obtaining results and cost of the technique was implemented. The results showed that, depending on the balance between the interest in ascertaining the trigger of degradation or deep into the knowledge of the causes and effects of cell culture viability, an appropriate plan of analysis of the validation of polyester-based scaffolds could be designed., The authors would like to acknowledge the Spanish Ministry of Education, Culture and Sports for the predoctoral FPU grant of O. Gil-Castell (FPU13/01916). Generalitat Valenciana is thanked for the APOSTD/2014/041 for J.D. Badia. D. Castellano and I. Ontoria-Oviedo thanked RESOLTEX (Ministry of Economy, Industry and Competitiveness RETOS, RTC-2015-4185-1) and P. Sepulveda acknowlewdges ISCIII for I3SNS Program.

The decomposition behaviours of composites made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and sisal were assessed in terms of thermal stability and decomposition kinetics, under inert and oxidative conditions, by means of multi-rate linear non-isothermal thermogravimetric experiments. A statistical design of experiments was applied to study the influence of the addition of sisal (0-10-20-30%wt), the presence coupling agent (Yes/No) and the applied conditions of work (inert or oxidative). An improvement of the thermal and thermo-oxidative stability of PHBV with the addition of sisal was observed for all cases. An accurate methodology based on iso-conversional methods was applied to simulate the potential of thermal recovery technologies, such as pyrolysis and controlled combustion, to use these biocomposites after the end of their service life. The mathematical descriptions of both thermo-chemical reactions were helpful in the evaluation of the eventual optimal operational conditions to carry out a suitable energetic valorisation. A minimum of 240°C and 137 kJ/mol of activation energy in inert conditions and 236°C and 118 kJ/mol in oxidative conditions ensured the feasibility of the reactions regardless the composition of the PHBV/sisal biocomposites, which may ease the operability of further energy valorisation with the aim to turn biowaste into new fuels.

Dendronized polyethers give rise to columnar LC structures which can successfully act as cation transport materials. Therefore, we prepared two different materials, based on Poly(epichlorohydrin-co-ethylene oxide) (PECH-co-EO) grafted with methyl 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy] benzoate, containing 20% or 40% modified units, respectively. The obtained polymers were characterized by differential scanning calorimetry (DSC), X-ray diffraction and optical microscopy between crossed polars (POM) and compared to the unmodified PECH-co-EO. In order to reach efficient transport properties, homeotropically oriented membranes were prepared by a fine-tuned thermal annealing treatment and were subsequently investigated by dynamic mechanical thermal analysis (DMTA) and dielectric thermal analysis (DETA). We found that the presence of the dendrons induces a main chain partial crystallization of the polyether chain and coherently increases the polymer Tg. This effect is more evident in the oriented membranes. As for copolymer orientation upon annealing, the cooling rate and the annealing temperature were the most crucial factors. DMTA and DETA confirmed that grafting with the dendron strongly hinders copolymer motions, but did not show great differences between unoriented and oriented membranes, regardless of the amount of dendrons.

In the present study, the dielectric properties of both neat and plasticized polylactide submitted to repeated extrusion and injection processes to simulate recycling were analysed. The dielectric relaxation spectrum, consisting of β and α relaxation, revealed the relevance of both acryl-PEG based plasticization and thermo-mechanical degradation induced by repeated extrusion and grinding-injection reprocessing cycles on polylactide (PLA). The β-relaxation has its origin in the intramolecular local motions of pendant groups of the PLA backbone, while the α-relaxation is representative of the intermolecular large-scale segmental motions of the PLA backbone. The addition of acryl-PEG to PLA (pPLA) induced an increment in the apparent activation energies and temperatures of the β-relaxation due to the different nature of the acryl-pendant group in pPLA. Moreover, the crystallization rate of pPLA was much faster compared to that of neat PLA, which hindered the movements of the acryl-pendant group, thus requiring more energy to orient the dipoles. The plasticizing effect of acryl-PEG effectively aids the large-scale motions associated to the glass transition, which are the origin of the α-relaxation. The effect of reprocessing in PLA is less relevant than the addition of the acryl-PEG plasticizer, in terms of dielectric behaviour. With increasing the number of processing cycles, the crystallization rate of PLA gradually increased, but the permittivity was still much lower than that of pPLA, for which crystallinity remained constant. Nonetheless, for the case of the α-relaxation of pPLA, the rearrangements produced by chain scission induced an enhancement of the thermal activation of the orientation of the dipoles but reduced the dynamic fragility and increased the embrittlement of pPLA after reprocessing. These differences found in the relaxation spectrum and the molecular dynamics in the environment of the glass transition for PLA and pPLA, together with the embrittlement of pPLA after reprocessing, is what will determine the final use of one or the other recycled polymer.

[EN] The hydrolysis of the polycaprolactone (PCL) as a function of the dissolution time in a formic/acetic acid mixture was considered as a method for tailoring the morphology of nanofibrous PCL scaffolds. Hence the aim of this research was to establish a correlation between the dissolution time of the polymer in the acid solvent with the physicochemical properties of the electrospun nanofibrous scaffolds and their further service life behaviour. The physico-chemical properties of the scaffolds were assessed in terms of fibre morphology molar mass and thermal behaviour. A reduction of the molar mass and the lamellar thickness as well as an increase of the crystallinity degree were observed as a function of dissolution time. Bead-free fibres were found after 24 and 48 h of dissolution time with similar diameter distributions. The decrease of the fibre diameter distributions along with the apparition of beads was especially significant for scaffolds prepared after 72 h and 120 h of dissolution time in the acid mixture. The service life of the obtained devices was evaluated by means of in vitro validation under abiotic physiological conditions. All the scaffolds maintained the nanofibrous structure after 100 days of immersion in water and PBS. The molar mass was barely affected and the crystallinity degree and the lamellar thickness increased along immersion preventing scaffolds from degradation. Scaffolds prepared after 24 h and 48 h kept their fibre diameters whereas those prepared after 72 h and 120 h showed a significant reduction. This PCL tailoring procedure to obtain scaffolds that maintain the nanoscaled structure after such long in vitro evaluation will bring new opportunities in the design of long-term biomedical patches. (C) 2016 Elsevier Ltd. All rights reserved., The European Regional Development Funds and the Spanish Ministry of Economy and Competitiveness are acknowledged for the projects POLYCELL (ENE2014-53734-C2-1-R) and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is thanked for the pre-doctoral FPU grant of O. Gil-Castell (FPU13/01916) and the scholarship for a research stage of 0. Gil-Castell in Kungliga Tekniska Hogskolan (KTH). Generalitat Valenciana is thanked for the APOSTD/2014/041 for J.D. Badia. Universitat de Valencia (UV) and HS LaFe are acknowledged for the DERMASAFE project. The financial support given by the ICTH Royal Institute of Technology and the Universitat Politecnica de Valencia (UPV) are gratefully acknowledged. IESMAT S.A. and Malvern Instruments Ltd are recognised for their grateful collaboration.

[EN] Effective antimicrobial polymeric nanocomposites were prepared with low density polyethylene (LDPE) and zinc oxide nanoparticles by melt compounding. These nanoparticles (~17 nm) obtained by the sol¿gel method, were used both as-synthesized and modified organically with oleic acid (Mod-ZnO). Young¿s modulus increased ~15 and 18% for LDPE/ZnO and LDPE/Mod-ZnO, respectively, compared to neat LDPE. When these composites were irradiated with white light, they showed an increase with nanoparticle incorporation, and the antimicrobial properties against E. coli were ~96¿99%. The release of the Zn cations was related to the antimicrobial properties. These nanocomposites are attractive for use as food packaging without external irradiation., Financial support provided by the Innovation Found for Competitiveness of the Chilean Economic Development Agency (CORFO) under Grant 13CEI2-21839 is gratefully acknowledged.

The evaluation of the performance of polyesters under in vitro physiologic conditions is essential to design scaffolds with an adequate lifespan for a given application. In this line, the degradation-durability patterns of poly(lactide-co-glycolide) (PLGA), polydioxanone (PDO), polycaprolactone (PCL) and polyhydroxybutyrate (PHB) scaffolds were monitored and compared giving, as a result, a basis for the specific design of scaffolds from short-term to long-term applications. For this purpose, they were immersed in ultra-pure water and phosphate buffer solution (PBS) at 37 &deg, C. The scaffolds for short-time applications were PLGA and PDO, in which the molar mass diminished down to 20% in a 20&ndash, 30 days lifespan. While PDO developed crystallinity that prevented the geometry of the fibres, those of PLGA coalesced and collapsed. The scaffolds for long-term applications were PCL and PHB, in which the molar mass followed a progressive decrease, reaching values of 10% for PCL and almost 50% for PHB after 650 days of immersion. This resistant pattern was mainly ascribed to the stability of the crystalline domains of the fibres, in which the diameters remained almost unaffected. From the perspective of an adequate balance between the durability and degradation, this study may serve technologists as a reference point to design polyester-based scaffolds for biomedical applications.

[EN] Dielectric Thermal Analysis (DETA) of a series of new thermoset obtained by click chemistry was performed. The new thermosets were obtained by a dual-curing process consisting in a first photochemical thiol-ene, followed by a thermal thiol-epoxy starting from an allyl-terminated hyperbranched poly(ethyleneimine) (HBPEI) and different proportions of diglycidylether of bisphenol A (DGEBA) and the corresponding stoichiometric proportions of pentaerythritol tetrakis (3-mercaptopropionate, PETMP). The dielectric behaviour was obtained experimentally supressing the conductive effects. Two sub-Tg intramolecular non-cooperative gamma and beta relaxations and an intermolecular cooperative alpha-relaxation were detected. The gamma-relaxation was ascribed to the dipole orientation of the terminal thiol groups. Two gamma relaxations gamma(epo) and gamma(ene) were observed, according to the influence of the surroundings. Only thermosets with a content of flexible HBPEI/PETMP domains higher than a 50% w/w showed the gamma(ene) relaxation at lower temperatures and higher frequencies. The beta-relaxation was a non-Johari-Goldstein relaxation, ascribed to the dipole transfer of the linear -CH2-O-(C=O)-CH2-CH2- groups of the thiol constrained in the glassy state. The alpha-relaxation was ascribed to the long-term segmental movements of the thermosets, occurring during the transition from the glassy to the rubbery stage. A synergic effect of reducing the rigidity and compactness of the thermosets by the reduction of aromatic moieties of the DGEBA/PETMP units, and the increase of the flexibility induced by the addition of HBPEI/PETMP units affected the macromolecular movement of the thermosets., European Regional Development Funds and the Spanish Ministry of Science, Innovation and Universities for ENE2017-86711-C3-1-R, MAT2017-82849-C2-1-R, ENE2014-53734-C2-1-R, UPOV13-3E-1947 and projects. Ministry of Education for the FPU13/01916) for O. Gil-Castell. Generalitat de Catalunya for the 2017-SGR-77 project. Generalitat Valenciana for the APOSTD14/041 for JD Badia and GRISOLIA/2012/003 for R. Teruel-Juanes.

Composite membranes based on poly(vinyl alcohol) (PVA) and graphene oxide (GO) were prepared by solution-casting method to be used as proton exchange membranes (PEMs) in fuel cell (FC) applications. Bisulfonation was employed as a strategy to enhance the proton conductivity of these membranes. First, a direct sulfonation of the polymer matrix was accomplished by intra-sulfonation of the polymer matrix with propane sultone, followed by the inter-sulfonation of the polymer chains using sulfosuccinic acid (SSA) as a crosslinking agent. Furthermore, the addition of graphene oxide (GO) as inorganic filler was also evaluated to enhance the proton-conducting of the composite membranes. These membranes were fully characterized by scanning electron microscopy (SEM), Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and tensile tests. Besides, the proton conductivity of these membranes in a fully hydrated state was also analyzed by electrochemical impedance spectroscopy (EIS). The effect of the intra- and inter-sulfonation of the polymer matrix on the structural, morphological, thermal and mechanical properties of the membranes were determined. Increasing the density of sulfonic acid groups in the membranes resulted in a trade-off between a better proton conductivity (improving from 0.26 to 1.00 mS/cm) and a decreased thermal and mechanical stability. In contrast, the incorporation of GO nanoparticles into the polymer matrix improved the thermal and mechanical stability of both bisulfonated composite membranes. The proton conductivity appreciably increased by the combination of bisulfonation and introduction of GO nanoparticles into the polymer matrix. The sPVA/30SSA/GO composite membrane exhibited a proton conductivity of 1.95 mS/cm at 25 °C. The combination of the GO nanoparticles with the chemical bisulfonation approach of PVA allows thus assembling promising proton exchange membrane candidates for fuel cell applications.

The influence of the combined exposure to water and temperature on the behaviour of polylactide/sisal biocomposites coupled with maleic acid anhydride was assessed through accelerated hydrothermal ageing. The biocomposites were immersed in water at temperatures from 65 to 85 °C, between the glass transition and cold crystallisation of the PLA matrix. The results showed that the most influent factor for water absorption was the percentage of fibres, followed by the presence of coupling agent, whereas the effect of the temperature was not significant. Deep assessment was devoted to biocomposites subjected to hydrothermal ageing at 85 °C, since it represents the extreme degrading condition. The morphology and crystallinity of the biocomposites were evaluated by means of X-Ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The viscoelastic and thermal performance were assessed by means of dynamic mechanic thermal analysis (DMTA) and thermogravimetry (TGA). The presence of sisal generally diminished the thermal stability of the biocomposites, which was mitigated by the addition of the coupling agent. After composite preparation, the effectiveness of the sisal fibre was improved by the crystallisation of PLA around sisal, which increased the storage modulus and reduced the dampening factor. The presence of the coupling agent strengthened this effect. After hydrothermal ageing, crystallisation was promoted in all biocomposites therefore showing more fragile behaviour evidencing pores and cracks. However, the addition of coupling agent in the formulation of biocomposites contributed in all cases to minimise the effects of hydrothermal ageing., The authors would like to acknowledge the Spanish Ministry of Economy and Competitiveness, through the Research Project ENE2014-53734-C2-1-R and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is also thanked for the pre-doctoral FPU grant of O. Gil-Castell (FPU13/01916). Generalitat Valenciana is thanked for the APOSTD14/041 program for J.D. Badia. The Chilean Government is thanked for the 13CEI2-21839 project. The financial support given by the Prince of Songkla University and KTH Royal Institute of Technology is gratefully acknowledged.

In this work electrical properties of an epoxy resin (DGEBA/OTBG) reinforced with alumina (10 nm) or zinc oxide (100 nm) were studied. The dielectric breakdown, relative permittivity, conductivity and dielectric loss were measured in five different nanocomposites for each nanoparticle varying temperature whenever possible. An increase of 50 % of the dielectric breakdown at room temperature in nanocomposites reinforced with only 0.4 % of as-received alumina nanoparticles was obtained. Aiming to understand a relation between state of dispersion of nanofillers and some properties a filler dispersion index Nearest Neighbor Distance was calculated based on FIB/FESEM images of the nanocomposites. This index is related to the dispersion of breakdown probability data and to the best of our knowledge it is not discussed in any other work in the literature. Dielectric spectra provided evidences of the decrease of mobility of charge carriers in lower filler loading nanocomposites due to trapping of charge carriers at the interphase. The percolation threshold of the interphase was reached at higher filler loading nanocomposites than 6 % phr, where the charge carriers have more mobility leading to paths of conductivity. These results corroborates with the drop observed in the dielectric breakdown for percolated nanocomposites. Another important issue found in this work, is that there was no change in the free-volume of the nanocomposites compared to neat epoxy. It is possible to state that in our system free-volume can not explain the variation on dielectric behavior as pointed out in the literature., The financial support of activities by WEG, CAPES, CNPq and ITM are greatly appreciated.

[EN] A series of UV photocrosslinked and post-sulfonated membranes based on blends of styrene-ethylene-butylene-styrene triblock copolymer (SEBS) and divinylbenzene (DVB) were considered for the preparation of electrolytes for proton exchange membrane fuel cell (PEMFC) applications. Macromolecular dynamics of SEBS and SEBS-DVB membranes below and above the Tg, were analysed using dielectric thermal analysis (DETA). A sub-Tg intramolecular non-cooperative dielectric relaxation and two main relaxations, corresponding to the glass transitions of ethylene-butylene (EB) and styrene (S) blocks, were identified in the dielectric relaxation spectrum. The photocrosslinking and post-sulfonation processes affect to the entire dielectric relaxation spectrum, the apparent activation energy and the fragilities of both styrene (S) and ethylene-butylene (EB) blocks. Understanding the restrictions on the segmental mobility at low and high scale caused by both photocrosslinking and subsequent sulfonation is basic to provide an approach to ionic diffusivities. A correlation between relaxations processes and the performance of these membranes in H2/O2 - PEM single cells allows to estimate the behaviour of these membranes and to reengineer them, depending on the modification of the desired cell performance., The authors would like to thank the support of the European Union is through the European Regional Development Funds (ERDF) and the Spanish Ministry of Economy, Industry and Competitiveness, for the research projects POLYDECARBOCELL (ENE2017-86711-C3-1-R), REPICOMES (ENE2017-90932-REDT) and UPV-(PAID -10-19) SUB-1 grant for R. Teruel.

The use of nanotechnology along with the consideration of a functionalization and stabilization approach to poly(vinyl alcohol) (PVA) is considered useful for the preparation of cost-effective polyelectrolyte membranes. A set of nanocomposite and crosslinked membranes based on PVA/sulfosuccinic acid (SSA)/graphene oxide (GO) are prepared and analyzed as polyelectrolytes in direct methanol fuel cells (DMFCs). The crosslinking and sulfonation by the use of SSA enhances the stability and increase the proton-conducting sites in the PVA structure. The presence of GO augments the stability, remarkably decreases the methanol crossover, and enhances power density curves. An optimum value for proton conductivity is found for the 0.50 wt% of GO proportion, which decreases with higher concentrations of GO. Given the power density curve dependency on both the proton conductivity and the crossover reduction, the performance of these membranes as polyelectrolytes in DMFCs is strictly related to the balance between both factors. Therefore, a proportion of GO of 0.75 wt% may assure suitable proton conductivity of 3 mS cm−1 and high resistance to methanol permeability, reaching promising power density of 16 mW cm−2 with lower hydration levels.

Encapsulated fat-soluble powders containing vitamin A (VA) and E (VE) were prepared as a feasible additive for extruded feed products. The effect of the encapsulating agents (Capsul-CAP&reg, sodium caseinate-SC) in combination with Tween 80 (TW) as an emulsifier and maltodextrin (MD) as a wall material on the physicochemical properties of emulsions and powders was evaluated. First, nanoemulsions containing MD:CAP:TW:VA/VE and MD:SC:TW:VA/VE were prepared and characterized. Then, powders were obtained by means of spray-drying and analyzed in terms of the product yield, encapsulation efficiency, moisture content, porosity, surface morphology, chemical structure, and thermal properties and thermo-oxidative/thermal stability. Results showed that although nanoemulsions were obtained for all the compositions, homogeneous microcapsules were found after the drying process. High product yield and encapsulation efficiency were obtained, and the presence of the vitamins was corroborated. The characteristics of the powders were mainly influenced by the encapsulating agent used and also by the type of vitamin. In general, the microcapsules remained thermally stable up to 170 &deg, C and, therefore, the proposed encapsulation systems for vitamins A and E were suitable for the preparation of additives for the feed manufacturing through the extrusion process.

Nanofibrous scaffolds composed of polycaprolactone (PCL) and gelatin (Ge) were obtained through a hydrolytic assisted electrospinning process. The PCL-to-Ge proportion (100/0 to 20/80), as well as the dissolution time (24, 48, 72, 96, 120 h) into a 1:1 formic/acetic acid solvent before electrospinning were modified to obtain the different samples. A strong influence of these factors on the physicochemical properties of the scaffolds was observed. Higher Ge percentage reduced crystallinity, allowed a uniform morphology and increased water contact angle. The increase in the dissolution time considerably reduced the molar mass and, subsequently, fibre diameter and crystallinity were affected. During in vitro biocompatibility tests, higher cell adhesion and proliferation were found for the 60/40, 50/50 and 40/60 PCL/Ge compositions that was corroborated by MTT assay, fluorescence and microscopy. A weakened structure, more labile to the in vitro degradation in physiologic conditions was found for these compositions with higher dissolution times (72 and 96 h). Particularly, the 40/60 PCL/Ge scaffolds revealed an interesting progressive degradation behaviour as a function of the dissolution time. Moreover, these scaffolds were non-inflammatory, as revealed by the pyrogen test and after the 15-day subcutaneous in vivo implantation in mice. Finally, a reduction of the scar tissue area after infarction was found for the 40/60 PCL/Ge scaffolds electrospun after 72 h implanted in rat hearts. These results are especially interesting and represent a feasible way to avoid undesired inflammatory reactions during the scaffold assimilation.

[EN] A series of bionanocomposite films based on chitosan, reinforced with chitin nanocrystals, were developed, and assessed in terms of dielectric behaviour and conductivity by using an experimental methodology that allows avoiding the conductivity contribution and the exclusion of contact and interfacial polarization effects. The dielectric relaxations at low and high frequency and temperatures were modeled by Havriliak-Negami functions. Below the glass transition temperature (Tg), the gamma and beta relaxations were observed, which were related to intramolecular and non-cooperative segmental movements. At higher temperatures, an intermolecular and cooperative macromolecular movement, related to the glass transition, gave rise to alpha-relaxation. In addition, two over-Tg p(I) and p(II) relaxations were found, which were related to the displacement of dipoles in the disordered structure of bionanocomposites. The addition of chitin nanocrystals did not affect the apparent activation energy Ea of the gamma-relaxation. However, it decreased the Ea of the beta-relaxation and increased the free volume at temperatures in the vicinities of the alpha-relaxation. Finally, the electric conductivity of the bionanocomposites was lower than that of neat chitosan and chitin due to the interaction between the-OH and-NH2 groups that reduced the ionic mobility, along with the increase of free volume, with the subsequent separation of phases., The European Regional Development Funds and the Spanish Ministry of Science and Innovation for the concession of Research Projects ENE2014-53734-C2-1-R, UPOV13-3E-1947 and ENE2017-86711-C3-1-R are appreciated. Generalitat Valenciana is acknowledged for the project APOSTD14/041 for JD Badia and GRISOLIA/2002/003 for R. Teruel-Juanes. The authors are thankful for the financial support from the Department of Education of the Basque Government (IT1008-18).

Graphene nanoplatelets (GNPs) were synthetized from graphite powder and, thereafter, embedded in poly(ethylene-co-vinyl alcohol) (EVOH) fibers by electrospinning in the 0.1&ndash, 2 wt.-% range. The morphological, chemical, and thermal characterization performed on the electrospun nanocomposite fibers mats revealed that the GNPs were efficiently dispersed and rolled along the EVOH fibrilar matrix up to contents of 0.5 wt.-%. Additionally, the dielectric behavior of the nanocomposite fibers was evaluated as a function of the frequency range and GNPs content. The obtained results indicated that their dielectric constant rapidly decreased with the frequency increase and only increased at low GNPs loadings while the nanocomposite fiber mats became electrically conductive, with the maximum at 0.5 wt.-% GNPs content. Finally, the electrospun mats were subjected to a thermal post-treatment and dark films with a high contact transparency were obtained, suggesting that the nanocomposites can be used either in a nonwoven fibers form or in a continuous film form. This study demonstrates the potential of electrospinning as a promising technology to produce GNPs-containing materials with high electrical conductivity that can be of potential interest in intelligent packaging applications as &ldquo, smart&rdquo, labels or tags.

The curing of composite materials is one of the parameters that most affects their mechanical behavior. The inspection methods used do not always allow a correct characterization of the curing state of the thermosetting resins. In this work, Raman spectroscopy technology is used for measuring the degree of cure. The results are compared with conventional thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscope (SEM). Carbon fiber specimens manufactured with technologies out of autoclave (OoA) have been used, with an epoxy system Prepreg System, SE 84LV. The results obtained with Raman technology show that it is possible to verify the degree of polymerization, and the information is complementary from classical thermal characterization techniques such as TGA and DSC, thus, it is possible to have greater control in curing and improving the quality of the manufactured parts.

[EN] A blending strategy of virgin and reprocessed polylactide may be postulated as an alternative to reduce the material cost at industrial level, and as a valorisation route to plastic waste management of production scraps. The performance of blends prepared from virgin polylactide and polylactide mechanically reprocessed up to two cycles (PLA-V/R) was assessed in terms of thermo-oxidative stability, morphology, viscoelasticity and thermal kinetics for energetic valorisation. PLA-V/R blends showed appropriate thermo-oxidative stability. The amorphous nature of polylactide was preserved after blending. The viscoelastic properties showed an increment of the mechanical blend effectiveness, which suggested the feasibility of PLA-V/R blends to be used under similar mechanical conditions to those of virgin PLA goods. Finally, it was shown that the energetic valorisation of PLA-V/R blends would result in a more feasible process, due to the lower required activation energy, thus highlighting the advantages of the energetic demand for the process. In conclusion, PLA-V/R blends showed similar processability, service performance and valorisation routes than virgin PLA and therefore could be relevant in the sustainable circular industry of bioplastics., The authors would like to thank the support of the European Regional Development Fund and the Spanish Ministry of Economy and Competitiveness, through the Research Projects ENE2014-53734-C2-1-R and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is also thanked for the FPU grant for O. Gil-Castell (FPU13/01916). Generalitat Valenciana is recognized for the APOSTD14/041 program for J.D. Badia.

[EN] We have prepared a series of new ionically conducting polymer electrolytes consisting of side-chain liquid crystal terpolymers with mesogenic azobenzenes, sulfonic acid groups and methyl methacrylate. The poly[10-(4-methoxyazobenzene -4'-oxy)decyl methacrylate] -co-poly[2-acrylamido-2-methyl-1-propanesulfonic acid]-copoly [methyl methacrylate]s, 10-MeOAzB/AMPS/MMA terpolymers, were synthesised by a one-pot conventional radical polymerisation. All samples were characterised by NMR, GPC/SEC, FT-IR, POM, XRD, DSC, UV-visible spectrophotometry and EIS. The terpolymers have light responsive properties, and exhibit liquid crystallinity over a wide range of compositions. Above a certain threshold of AMPS content, the 10-MeOAzB/AMPS/MMA terpolymers exhibit ionic conductivities in the 10(-8)-10(-4)S.cm(-1) range, with signs of decoupling of ionic mobility from segmental motions of the polymer., ARG and AMF thank the financial support of the Generalitat Valenciana, through the Grisolia and Forteza programs, and the Spanish Ministry of Science and Innovation, through the Research Projects ENE2007-67584-C03 and UPOVCE-3E-013 and the awarding of two FPI and FPU pre-doctoral grants. AMF and NFKA would like to thank the Royal Academy of Engineering for the award of the Newton Research Collaboration Programme grant NRCP1516/4/61. AMF acknowledges the School of Engineering of the University of Aberdeen for financial support.

[EN] Self-reinforced polymer composites (SRCs) are proposed as a suitable alternative for composite development, based in the combination of a polymeric matrix and a polymeric fibre made of the same polymer. SRCs based in polylactide (PLA) could be fully biodegradable and their valorisation routes could presumably be assimilated to those for neat PEA. In this sense, the aim of this study was to develop new self-reinforced PLA-based composites and ascertain their biodegradability. For this purpose, PLA-based SRCs were obtained through a thermo-compression procedure and their biodegradability corroborated under standard conditions (ISO 20200). Moreover, a deep study of the effect of the different factors involved in the biodegradation of the composites such as the temperature, the water and the compost medium was considered relevant to delimitate the long-term properties and valorisation routes for these materials. The macroscopic and microscopic appearance as well as the thermo-oxidative stability, the thermal properties and the molar mass were evaluated. Although degradation was perceived due to the effect of temperature, the synergistic combination of water and temperature and compost was found to play a key role in the biodegradation of these materials. Overall, these SRCs can be considered as promising candidates, since their end-of-life management options can be guaranteed under standardised composting conditions. (C) 2018 Elsevier Ltd. All rights reserved., The authors would like to thank the support of the European Regional Development Fund and the Spanish Ministry of Economy and Competitiveness, through the Research Projects ENE2014-53734-C2-1-R and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is also thanked for the FPU grant for O. Gil-Castell (FPU13/01916). Generalitat Valenciana is recognised for the APOSTD14/041 program for J.D. Badia.

[EN] Blended nanofibrous scaffolds based on polycaprolactone (PCL) and gelatin (Ge) were successfully prepared. A formic/acetic acid (1:1) mixture was used to dissolve PCL/Ge blends from 100/0 to 20/80 %wt in steps of 10 %wt. The hydrolysis of the PCL diluted in the formic/acetic acid mixture was considered as a method for tailoring the surface morphology and physicochemical features of the nanofibrous PCL/Ge scaffolds as a function of the dissolution time. The fibre diameter remained in the nanoscale range for all the studied scaffolds, which is crucial to mimic the extra-cellular matrix size. The reduction of the intrinsic viscosity, molar mass and hydrodynamic radius found for the PCL molecules as a function of the dissolution time, consequently diminished the entanglement capability of the polymeric chains. Subsequently, the fibre diameter decreased as dissolution time increased, for all the studied compositions. While the crystallinity of the scaffolds with high PCL content increased as a function of the dissolution time, the scaffolds with high percentage of Ge showed the lowest crystallinity degree, which was ascribed to the hindering effect of the Ge diffused among the PCL segments. The wettability increased as a function of the Ge content due to the high hydrophilic behaviour of these molecules. It also increased as a function of the dissolution time, due to the more hydroxyl groups available in PCL segments to interact with water molecules. As a whole, the physicochemical assessment of the electrospun scaffolds revealed an effective tailoring procedure to obtain functionalised PCL/Ge scaffolds with specific properties as a function of the dissolution time before electrospinning., The Spanish Ministry of Economy and Competitiveness is acknowledged for the projects POLYCELL (ENE2014-53734-C2-1-R), POLYDECARBOCELL (ENE2017-86711-C3-1-R) and UPOV13-3E-1947. The Spanish Ministry of Education, Culture and Sports is thanked for the pre-doctoral FPU grant of O. Gil-Castell (FPU13/01916). Generalitat Valenciana is thanked for the APOSTD/2014/041 for J.D. Badia.

Oxidation of polyolefins by ultraviolet/visible irradiation is a significant limitation for their use in several technological applications. The use of high-tech additives such as silicon microparticles becomes a compositing strategy that can improve the performance of these materials at long-term service conditions. Silicon particles were added to non-additivated raw polypropylene (PP) prepared by hot melt extrusion and subjected to accelerated sunlight irradiation tests. The stability of thermal properties, mechanical performance and thermal decomposition behaviour of composites was evaluated by differential scanning calorimetry, dynamic mechanical thermal analysis and thermogravimetry. This paper shows the potential of silicon microparticles to protect PP from degradation during both processing and accelerated sunlight irradiation. The addition of polydisperse silicon microparticles to the raw polypropylene preserved the appearance and improved the thermal behaviour, mechanical properties and thermal stability. It was found that silicon particles at 5 wt% provided a suitable protection of raw non-additivated PP against sunlight irradiation., B.Sc. A. Montesinos is acknowledged for his dedication in the lab and his outstanding attitude towards learning. Ph.D. L. Santonja-Blasco is thanked for revision of the work and endless and enjoyable discussions. The authors would like to acknowledge the Spanish Ministry of Economy and Competitiveness, through the Research Project MAT2012-3504. The Spanish Ministry of Education, Culture and Sports is also thanked for the predoctoral FPU grant of O. Gil-Castell (FPU13/01916). Generalitat Valenciana is thanked for the PROMETEOII/2014/026, the APOSTD 2014/041 of J.D. Badia and the GRISOLIA/2012/003 for R. Teruel-Juanes. Universitat Politecnica de Valencia is thanked for the support through the PAID-06-SP20120581 project and for the FPI grant of O. Gil-Castell. Repsol (Tarragona, Spain) is acknowledged for providing the raw polypropylene (PP) homopolymer.

Una de las competencias transversales que entraña mayor grado de dificultad en su implementación, adquisición a todos los niveles, y evaluación es la de “Innovación, creatividad y emprendimiento”. La innovación se entiende como la capacidad de dar respuesta satisfactoria a las necesidades personales, organizativas y sociales, modificando procesos y/o resultados para generar nuevo valor. La innovación necesita ir acompañada de la creatividad para generar ideas y del emprendimiento para transformar las ideas en un producto de valor. En este trabajo se describe el diseño de estrategias docentes integradas en el marco de la corriente de educación emprendedora, centradas en el aprendizaje basado en problemas y colaborativo, para desarrollar dicha competencia. La acción se lleva a cabo en diferentes asignaturas de primer curso en distintos títulos de Grado en la Universitat Politècnica de València. Se describen las acciones realizadas, se analizan los resultados obtenidos y se valora la transferibilidad a otros contextos, tras la implementación del plan de trabajo para cada asignatura. Se concluye que las acciones llevadas a cabo han contribuido a desarrollar la competencia indicada y a que los estudiantes experimenten el valor del aprendizaje activo y del trabajo colaborativo. [One of the most difficult transversal competences to implement, acquire at all levels and evaluate, is that of "Innovation, creativity and entrepreneurship". Innovation is understood as the ability to satisfy personal, organizational and social needs, modifying processes and/or results to generate new value. Innovation needs to be accompanied by creativity to generate ideas and by entrepreneurship to transform ideas into a valuable product. This paper describes the design of teaching strategies integrated within the framework of entrepreneurship education, focused on problem-based and collaborative learning, to develop this competence. The experiences are carried out in different first year subjects from different degrees offered by the Universitat Politècncia de València. After the implementation of the work plan for each subject, actions performed are described and results obtained are analysed in order to assess the transferability to other contexts. It is concluded that the actions carried out contributed to develop the indicated skill and allowed students to experience the value of active learning and collaborative work.]

[EN] The long-term properties and end-of-life of polymers are not antagonist issues. They actually are inherently linked by the duality between durability and degradation. The control of the service-todisposal pathway at useful performance, along with low-impact disposal represents an added-value. Therefore, the routes of design, production, and discarding of bio-based polymers must be carefully strategized. In this sense, the combination of proper valorisation techniques, i.e. material, energetic and/ or biological at the most appropriate stage should be targeted. Thus, the consideration of the end-of-life of a material for a specific application, instead of the end-of-life of a material should be the fundamental focus. This review covers the key aspects of lab-scale techniques to infer the potential of performance and valorisation of polymers from renewable resources as a key gear for sustainability., The authors acknowledge the European Funds of Regional Development and the Spanish Ministry of Economy and Competitiveness for the projects POLYCELL (ENE2014-53734-C2-1-R) and TETRA-SEC (UPOV13-3E-1947). Generalitat Valenciana is recognized for the BIOARMED project (APOSTD/2014/041) for J.D. Badia. The Spanish Ministry of Education, Culture and Sports is thanked for the FPU grant of O. Gil-Castell (FPU13/01916). J.D. Badia wants to dedicate this article to his wife Mireia, for her peaceful dedication and joyful love.

[EN] The extent of the ultraviolet¿visible (UV¿vis) photoirradiation effect on high-density polyethylene (HDPE) and HDPE¿sili-con (Si) composites is reported in terms of the addition of Si microparticles at contents of 0.1, 1, and 5 wt %. A standard acceleratedUV-vis exposure was applied over 2750 h, corresponding to 22 months in Florida. Thermogravimetry, differential scanning calorimetry,and Fourier transform infrared spectroscopy were used as reliable techniques for monitoring the quality of the HDPE-Si composites. Theincreasing addition of Si microparticles delayed the photodegradation of the HDPE¿Si composites. Because of their strong light-scattering effects, Si microparticles blocked the degradation of ter tiary carbons of the HDPE backbone and reduced the apparition ofvinyl groups; this prevented the structural impoverishment of HDPE-Si composites. Consequently, variations in the crystallization tem-perature (Tc) and melting temperature (Tm), which were indicators of photodegradation, were not modified. In general, the HDPE-Sicomposite formulation with 5 wt % Si microparticles was useful for protecting the material from photodegradation and, thus, should bean environmentally friendly, reliable alternative UV-vis blocker., Funding of this work by the European Regional Development Funds and the Spanish Ministry of Economy and Competitiveness through research projects ENE2014-53734-C2-1-R, MAT2012-35040 and the excellence programme Severo Ochoa (SEV-2016-0683) is acknowledged. One of the authors (S.S.-B.) appreciates a Formacion de Personal Investigador predoctoral grant (contract grant number BES-2012-055316). Generalitat Valenciana is thanked for grants to L. Santonja-Blasco (contract grant numbers APOSTD/2013/036) and J. D. Badia (contract grant number APOSTD/2014/041) and funding through research project PROM-ETEOII/2014/026. Universitat Politecnica de Valencia is also thanked for its support (contract grant number PAID-06-SP20120581). The authors acknowledge Puerto Asensio Bros from Inyeccion de Plasticos (Bocairent, Valencia, Spain) for kindly supplying the polymer and L. Cabedo from Jaume I University (Castello, Spain) for providing technical assistance with the preparation of the samples. Finally, the authors thank the Electron Microscopy Service of Universitat Politecnica de Valencia for its support.

[EN] The eco-design considers the factors to prepare biocomposites under an end-of-life scenario. PLA/sisal biocomposites were obtained from amorphous polylactide and sisal loadings of 10, 20 and 30 wt% with and without coupling agent, and subjected to biodegradation in soil according to standard IS0846. Mass loss, differential scanning calorimetry and size-exclusion chromatography were used for monitoring biodegradation. A statistical factorial analysis based on the molar mass M-n, and crystallinity degree X-c pointed out the relevance and interaction of amount of fibre and use of coupling agent with the time of burial in soil., During the preparation of biocomposites, chain scission provoked a similar reduction of M-n, for coupled and non-coupled biocomposites. The amount of fibre was relevant for the increase of Xc due to the increase of nucleation sites. The coupling agent accelerated the evolution of both factors: reduction of M-n, and the consequent increase of Xc, mainly during biodegradation in soil. Both factors should be balanced to facilitate microbial assimilation of polymer segments, since bacterial digestion is enhanced by chain scission but blocked by the promotion of crystalline fractions. (C) 2017 Elsevier Ltd. All rights reserved., The authors would like to acknowledge the European Regional Development Funds and the Spanish Ministry of Economy and Competitiveness, through the Research Projects ENE2014-53734-C2-1-R and UPOV13-3E-1947. Generalitat Valenciana is thanked for the APOSTDI4/041 program for J.D. Badia. The financial support given by the Prince of Songkla University and KTH Royal Institute of Technology is gratefully acknowledged.