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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.
B. Pascual-Jose; J.D. Badia; A. Múgica; Frédéric Addiego; Alejandro J. Müller; A. Ribes-Greus. Analysis of plasticization and reprocessing effects on the segmental cooperativity of polylactide by dielectric thermal spectroscopy. Polymer 2021, 223, 123701 .
AMA StyleB. Pascual-Jose, J.D. Badia, A. Múgica, Frédéric Addiego, Alejandro J. Müller, A. Ribes-Greus. Analysis of plasticization and reprocessing effects on the segmental cooperativity of polylactide by dielectric thermal spectroscopy. Polymer. 2021; 223 ():123701.
Chicago/Turabian StyleB. Pascual-Jose; J.D. Badia; A. Múgica; Frédéric Addiego; Alejandro J. Müller; A. Ribes-Greus. 2021. "Analysis of plasticization and reprocessing effects on the segmental cooperativity of polylactide by dielectric thermal spectroscopy." Polymer 223, no. : 123701.
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.
Roberto Teruel-Juanes; Krzysztof Bogdanowicz; Jose Badia; Victor Sáenz de Juano-Arbona; Robert Graf; Jose Reina; Marta Giamberini; Amparo Ribes-Greus. Molecular Mobility in Oriented and Unoriented Membranes Based on Poly[2-(Aziridin-1-yl)ethanol]. Polymers 2021, 13, 1060 .
AMA StyleRoberto Teruel-Juanes, Krzysztof Bogdanowicz, Jose Badia, Victor Sáenz de Juano-Arbona, Robert Graf, Jose Reina, Marta Giamberini, Amparo Ribes-Greus. Molecular Mobility in Oriented and Unoriented Membranes Based on Poly[2-(Aziridin-1-yl)ethanol]. Polymers. 2021; 13 (7):1060.
Chicago/Turabian StyleRoberto Teruel-Juanes; Krzysztof Bogdanowicz; Jose Badia; Victor Sáenz de Juano-Arbona; Robert Graf; Jose Reina; Marta Giamberini; Amparo Ribes-Greus. 2021. "Molecular Mobility in Oriented and Unoriented Membranes Based on Poly[2-(Aziridin-1-yl)ethanol]." Polymers 13, no. 7: 1060.
This paper describes the planning of a computer-aided design (CAD) laboratory for training chemical engineers in graphic expression. The CAD laboratory was organised into four projects following a project-based learning method. Flipped classroom and contextualised learning were used to motivate the students and promote meaningful learning. The laboratory mainly focused on engaging the students by replicating 2D and 3D plans of common industrial engineering equipment and piping and instrumentation diagrams of industrial facilities. Two surveys carried out before and after the course showed that the student’s perception of their graphic expression skills significantly increased. Gender differences were observed in self-perceived graphic expression skills, particularly in spatial vision. The results showed considerable overall satisfaction with the method, scoring a value of 4.1 ± 0.9 in the Likert scale (maximum 5). Most of the students obtained a score higher than 8 in the CAD laboratory, showing their acquisition of specific competences. The results encouraged us to apply this method to subsequent courses and to extend training in graphic expression to other subjects in the chemical engineering degree. The method followed here can easily be extrapolated to other engineering disciplines.
María Hernáiz-Pérez; Javier Álvarez-Hornos; José David Badia; Juan Bautista Giménez; Ángel Robles; Victoria Ruano; Pau San-Valero. Contextualized project-based learning for training chemical engineers in graphic expression. Education for Chemical Engineers 2020, 34, 57 -67.
AMA StyleMaría Hernáiz-Pérez, Javier Álvarez-Hornos, José David Badia, Juan Bautista Giménez, Ángel Robles, Victoria Ruano, Pau San-Valero. Contextualized project-based learning for training chemical engineers in graphic expression. Education for Chemical Engineers. 2020; 34 ():57-67.
Chicago/Turabian StyleMaría Hernáiz-Pérez; Javier Álvarez-Hornos; José David Badia; Juan Bautista Giménez; Ángel Robles; Victoria Ruano; Pau San-Valero. 2020. "Contextualized project-based learning for training chemical engineers in graphic expression." Education for Chemical Engineers 34, no. : 57-67.
The influence of the addition of graphene nanoplatelets (GNPs) on the intra/inter – molecular segmental motions of poly(ethylene-co-vinyl alcohol) (EVOH) was assessed by means of dielectric thermal analysis (DETA). The relaxation spectra were studied in terms of the dielectric permittivity (ε′) and the dielectric loss tangent (tan δ) at wide ranges of frequency (from 10−2 to 107 Hz) and temperature (from -150 to 140 °C). Two relaxation zones were disthinguished. Below the glass transition temperature (Tg), two β-relaxations were observed, which are characteristic local modes of mobility of the EVOH side groups, and related to the influence of the different surroundings of ethylene or vinyl alcohol units. At higher temperatures, the dielectric α-relaxation in the vicinities of the glass transition of EVOH was determined. The thermal activation of the β-relaxations was explained by an Arrhenius model, and showed activation energies (Ea) around 55 and 80 kJ·mol−1. The α-relaxation was explained by the Vogel-Fulcher-Tammann-Hesse (VFTH) model. The study of the segmental dynamics showed an increase in the dynamic fragility parameters with the addition of GNPs. The permittivity was increased at preferential concentrations of GNPs. In particular, the addition of GNPs up to 0.5 wt% increased the dielectric permittivity of the electrospun EVOH/GNPs nanocomposite fibers, specially at low frequencies.
J.D. Badia; R. Teruel-Juanes; Y. Echegoyen; S. Torres-Giner; J.M. Lagarón; A. Ribes-Greus. Effect of graphene nanoplatelets on the dielectric permittivity and segmental motions of electrospun poly(ethylene-co-vinyl alcohol) nanofibers. Polymer Degradation and Stability 2020, 183, 109404 .
AMA StyleJ.D. Badia, R. Teruel-Juanes, Y. Echegoyen, S. Torres-Giner, J.M. Lagarón, A. Ribes-Greus. Effect of graphene nanoplatelets on the dielectric permittivity and segmental motions of electrospun poly(ethylene-co-vinyl alcohol) nanofibers. Polymer Degradation and Stability. 2020; 183 ():109404.
Chicago/Turabian StyleJ.D. Badia; R. Teruel-Juanes; Y. Echegoyen; S. Torres-Giner; J.M. Lagarón; A. Ribes-Greus. 2020. "Effect of graphene nanoplatelets on the dielectric permittivity and segmental motions of electrospun poly(ethylene-co-vinyl alcohol) nanofibers." Polymer Degradation and Stability 183, no. : 109404.
Ramón Jiménez Robles; José David Badia Valiente; Carmen Gabaldón García; Vicente Martínez Soria; Marta Izquierdo Sanchis. Surface modification of membranes for methane degassing from water: preliminary study on hydrophobicity and performance. 14th Mediterranean Congress of Chemical Engineering (MeCCE14) Abstracts Publication 2020, 1 .
AMA StyleRamón Jiménez Robles, José David Badia Valiente, Carmen Gabaldón García, Vicente Martínez Soria, Marta Izquierdo Sanchis. Surface modification of membranes for methane degassing from water: preliminary study on hydrophobicity and performance. 14th Mediterranean Congress of Chemical Engineering (MeCCE14) Abstracts Publication. 2020; ():1.
Chicago/Turabian StyleRamón Jiménez Robles; José David Badia Valiente; Carmen Gabaldón García; Vicente Martínez Soria; Marta Izquierdo Sanchis. 2020. "Surface modification of membranes for methane degassing from water: preliminary study on hydrophobicity and performance." 14th Mediterranean Congress of Chemical Engineering (MeCCE14) Abstracts Publication , no. : 1.
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.
O. Gil-Castell; J.D. Badia; I. Ontoria-Oviedo; D. Castellano; P. Sepúlveda; A. Ribes-Greus. Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation. Materials Science and Engineering: C 2019, 107, 110296 .
AMA StyleO. Gil-Castell, J.D. Badia, I. Ontoria-Oviedo, D. Castellano, P. Sepúlveda, A. Ribes-Greus. Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation. Materials Science and Engineering: C. 2019; 107 ():110296.
Chicago/Turabian StyleO. Gil-Castell; J.D. Badia; I. Ontoria-Oviedo; D. Castellano; P. Sepúlveda; A. Ribes-Greus. 2019. "Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation." Materials Science and Engineering: C 107, no. : 110296.
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.
O. Gil-Castell; R. Teruel-Juanes; F. Arenga; A.M. Salaberria; M.G. Baschetti; J. Labidi; J.D. Badia; A. Ribes-Greus. Crosslinked chitosan/poly(vinyl alcohol)-based polyelectrolytes for proton exchange membranes. Reactive and Functional Polymers 2019, 142, 213 -222.
AMA StyleO. Gil-Castell, R. Teruel-Juanes, F. Arenga, A.M. Salaberria, M.G. Baschetti, J. Labidi, J.D. Badia, A. Ribes-Greus. Crosslinked chitosan/poly(vinyl alcohol)-based polyelectrolytes for proton exchange membranes. Reactive and Functional Polymers. 2019; 142 ():213-222.
Chicago/Turabian StyleO. Gil-Castell; R. Teruel-Juanes; F. Arenga; A.M. Salaberria; M.G. Baschetti; J. Labidi; J.D. Badia; A. Ribes-Greus. 2019. "Crosslinked chitosan/poly(vinyl alcohol)-based polyelectrolytes for proton exchange membranes." Reactive and Functional Polymers 142, no. : 213-222.
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 °C. The scaffolds for short-time applications were PLGA and PDO, in which the molar mass diminished down to 20% in a 20-30 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.
Oscar Gil-Castell; José David Badia; Jordi Bou; Amparo Ribes-Greus. Performance of Polyester-Based Electrospun Scaffolds under In Vitro Hydrolytic Conditions: From Short-Term to Long-Term Applications. Nanomaterials 2019, 9, 786 .
AMA StyleOscar Gil-Castell, José David Badia, Jordi Bou, Amparo Ribes-Greus. Performance of Polyester-Based Electrospun Scaffolds under In Vitro Hydrolytic Conditions: From Short-Term to Long-Term Applications. Nanomaterials. 2019; 9 (5):786.
Chicago/Turabian StyleOscar Gil-Castell; José David Badia; Jordi Bou; Amparo Ribes-Greus. 2019. "Performance of Polyester-Based Electrospun Scaffolds under In Vitro Hydrolytic Conditions: From Short-Term to Long-Term Applications." Nanomaterials 9, no. 5: 786.
Taking advantage of the high functionalization capacity of poly(vinyl alcohol) (PVA), bead-free homogeneous nanofibrous mats were produced. The addition of functional groups by means of grafting strategies such as the sulfonation and the addition of nanoparticles such as graphene oxide (GO) were considered to bring new features to PVA. Two series of sulfonated and nonsulfonated composite nanofibers, with different compositions of GO, were prepared by electrospinning. The use of sulfosuccinic acid (SSA) allowed crosslinked and functionalized mats with controlled size and morphology to be obtained. The functionalization of the main chain of the PVA and the determination of the optimum composition of GO were analyzed in terms of the nanofibrous morphology, the chemical structure, the thermal properties, and conductivity. The crosslinking and the sulfonation treatment decreased the average fiber diameter of the nanofibers, which were electrical insulators regardless of the composition. The addition of small amounts of GO contributed to the retention of humidity, which significantly increased the proton conductivity. Although the single sulfonation of the polymer matrix produced a decrease in the proton conductivity, the combination of the sulfonation, the crosslinking, and the addition of GO enhanced the proton conductivity. The proposed nanofibers can be considered as good candidates for being exploited as valuable components for ionic polyelectrolyte membranes.
Oscar Gil-Castell; Diana Galindo-Alfaro; Soraya Sánchez-Ballester; Roberto Teruel-Juanes; José David Badia; Amparo Ribes-Greus. Crosslinked Sulfonated Poly(vinyl alcohol)/Graphene Oxide Electrospun Nanofibers as Polyelectrolytes. Nanomaterials 2019, 9, 397 .
AMA StyleOscar Gil-Castell, Diana Galindo-Alfaro, Soraya Sánchez-Ballester, Roberto Teruel-Juanes, José David Badia, Amparo Ribes-Greus. Crosslinked Sulfonated Poly(vinyl alcohol)/Graphene Oxide Electrospun Nanofibers as Polyelectrolytes. Nanomaterials. 2019; 9 (3):397.
Chicago/Turabian StyleOscar Gil-Castell; Diana Galindo-Alfaro; Soraya Sánchez-Ballester; Roberto Teruel-Juanes; José David Badia; Amparo Ribes-Greus. 2019. "Crosslinked Sulfonated Poly(vinyl alcohol)/Graphene Oxide Electrospun Nanofibers as Polyelectrolytes." Nanomaterials 9, no. 3: 397.
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 γ and β relaxations and an intermolecular cooperative α-relaxation were detected. The γ-relaxation was ascribed to the dipole orientation of the terminal thiol groups. Two γ relaxations γepo and γene 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 γene relaxation at lower temperatures and higher frequencies. The β-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 α-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.
J.D. Badia; R. Teruel-Juanes; C. Acebo; O. Gil-Castell; A. Serra; A. Ribes-Greus. Dielectric spectroscopy of novel thiol-ene/epoxy thermosets obtained from allyl-modified hyperbranched poly(ethyleneimine) and diglycidylether of bisphenol A. European Polymer Journal 2019, 113, 98 -106.
AMA StyleJ.D. Badia, R. Teruel-Juanes, C. Acebo, O. Gil-Castell, A. Serra, A. Ribes-Greus. Dielectric spectroscopy of novel thiol-ene/epoxy thermosets obtained from allyl-modified hyperbranched poly(ethyleneimine) and diglycidylether of bisphenol A. European Polymer Journal. 2019; 113 ():98-106.
Chicago/Turabian StyleJ.D. Badia; R. Teruel-Juanes; C. Acebo; O. Gil-Castell; A. Serra; A. Ribes-Greus. 2019. "Dielectric spectroscopy of novel thiol-ene/epoxy thermosets obtained from allyl-modified hyperbranched poly(ethyleneimine) and diglycidylether of bisphenol A." European Polymer Journal 113, no. : 98-106.
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 °C and 174 kJ·mol-1 in inert environment and 225 °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.
C. Moliner; J.D. Badia; B. Bosio; E. Arato; R. Teruel-Juanes; T. Kittikorn; E. Strömberg; M. Ek; S. Karlsson; A. Ribes-Greus. Thermal kinetics for the energy valorisation of polylactide/sisal biocomposites. Thermochimica Acta 2018, 670, 169 -177.
AMA StyleC. Moliner, J.D. Badia, B. Bosio, E. Arato, R. Teruel-Juanes, T. Kittikorn, E. Strömberg, M. Ek, S. Karlsson, A. Ribes-Greus. Thermal kinetics for the energy valorisation of polylactide/sisal biocomposites. Thermochimica Acta. 2018; 670 ():169-177.
Chicago/Turabian StyleC. Moliner; J.D. Badia; B. Bosio; E. Arato; R. Teruel-Juanes; T. Kittikorn; E. Strömberg; M. Ek; S. Karlsson; A. Ribes-Greus. 2018. "Thermal kinetics for the energy valorisation of polylactide/sisal biocomposites." Thermochimica Acta 670, no. : 169-177.
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 presumably their valorisation routes could be assimilated to those for neat PLA. In this sense, the aim of this study was to develop new self-reinforced PLA-based composites and ascertain their biodegradability. Self-reinforced PLA-based composites were suitably 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 PLA-based self-reinforced composites such as the temperature, water and compost medium was considered relevant to delimitate the long-term properties and valorisation routes for these materials. For this purpose, 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 promising candidates, since their end-of-life management options can be guaranteed under standardised composting conditions.
Oscar Gil-Castell; J.D. Badia; S. Ingles-Mascaros; R. Teruel-Juanes; A. Serra; A. Ribes-Greus. Polylactide-based self-reinforced composites biodegradation: Individual and combined influence of temperature, water and compost. Polymer Degradation and Stability 2018, 158, 40 -51.
AMA StyleOscar Gil-Castell, J.D. Badia, S. Ingles-Mascaros, R. Teruel-Juanes, A. Serra, A. Ribes-Greus. Polylactide-based self-reinforced composites biodegradation: Individual and combined influence of temperature, water and compost. Polymer Degradation and Stability. 2018; 158 ():40-51.
Chicago/Turabian StyleOscar Gil-Castell; J.D. Badia; S. Ingles-Mascaros; R. Teruel-Juanes; A. Serra; A. Ribes-Greus. 2018. "Polylactide-based self-reinforced composites biodegradation: Individual and combined influence of temperature, water and compost." Polymer Degradation and Stability 158, no. : 40-51.
Graphene nanoplatelets (GNPs) were synthetized from graphite powder and, thereafter, embedded in poly(ethylene-co-vinyl alcohol) (EVOH) fibers by electrospinning in the 0.1–2 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 “smart” labels or tags.
Sergio Torres-Giner; Yolanda Echegoyen; Roberto Teruel-Juanes; Jose D. Badia; Amparo Ribes-Greus; Jose M. Lagaron. Electrospun Poly(ethylene-co-vinyl alcohol)/Graphene Nanoplatelets Composites of Interest in Intelligent Food Packaging Applications. Nanomaterials 2018, 8, 745 .
AMA StyleSergio Torres-Giner, Yolanda Echegoyen, Roberto Teruel-Juanes, Jose D. Badia, Amparo Ribes-Greus, Jose M. Lagaron. Electrospun Poly(ethylene-co-vinyl alcohol)/Graphene Nanoplatelets Composites of Interest in Intelligent Food Packaging Applications. Nanomaterials. 2018; 8 (10):745.
Chicago/Turabian StyleSergio Torres-Giner; Yolanda Echegoyen; Roberto Teruel-Juanes; Jose D. Badia; Amparo Ribes-Greus; Jose M. Lagaron. 2018. "Electrospun Poly(ethylene-co-vinyl alcohol)/Graphene Nanoplatelets Composites of Interest in Intelligent Food Packaging Applications." Nanomaterials 8, no. 10: 745.
An improved and more sustainable waste management system is required for successful development of technologies based on renewable sources. Rice straw is submitted to controlled combustion reactions and the produced ashes are chemically treated to produce silica. After a chemical activation step, the activated silica shows potential as an adsorbent agent and will be used to remove the excess of nitrates in groundwater and wells in the area of Alginet (Valencia, Spain), selected as a vulnerable zone within the Nitrates Directive. The demonstration activity aims to have a local impact on municipalities of 200 inhabitants or fewer, decreasing from current nitrate concentrations close to 50 mg/L, to a target of 25 mg/L. In a successive step, the methodology will be transferred to other municipalities with similar nitrate problems (Piemonte, Italy) and replicated to remove different pollutants such as manure (the Netherlands) and waste waters from the textile industry (Italy).
Cristina Moliner; Roberto Teruel-Juanes; Carmem T. Primaz; Jose David Badia; Barbara Bosio; Pilar Campíns-Falcó; Carmen Molíns-Legua; Francesc Hernandez; Lorenzo Sanjuan-Navarro; Plàcid Madramany; José Morán; José Castro; Francisco Javier Sanchis; José Domingo Martínez; Frank Hiddink; Amparo Ribes-Greus; Elisabetta Arato. Reduction of Nitrates in Waste Water through the Valorization of Rice Straw: LIFE LIBERNITRATE Project. Sustainability 2018, 10, 3007 .
AMA StyleCristina Moliner, Roberto Teruel-Juanes, Carmem T. Primaz, Jose David Badia, Barbara Bosio, Pilar Campíns-Falcó, Carmen Molíns-Legua, Francesc Hernandez, Lorenzo Sanjuan-Navarro, Plàcid Madramany, José Morán, José Castro, Francisco Javier Sanchis, José Domingo Martínez, Frank Hiddink, Amparo Ribes-Greus, Elisabetta Arato. Reduction of Nitrates in Waste Water through the Valorization of Rice Straw: LIFE LIBERNITRATE Project. Sustainability. 2018; 10 (9):3007.
Chicago/Turabian StyleCristina Moliner; Roberto Teruel-Juanes; Carmem T. Primaz; Jose David Badia; Barbara Bosio; Pilar Campíns-Falcó; Carmen Molíns-Legua; Francesc Hernandez; Lorenzo Sanjuan-Navarro; Plàcid Madramany; José Morán; José Castro; Francisco Javier Sanchis; José Domingo Martínez; Frank Hiddink; Amparo Ribes-Greus; Elisabetta Arato. 2018. "Reduction of Nitrates in Waste Water through the Valorization of Rice Straw: LIFE LIBERNITRATE Project." Sustainability 10, no. 9: 3007.
A series of bionanocomposite films based on chitosan, reinforced with chitin nanocrystals, were developed, and assessed in terms of dielectric behavior 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 γ and β 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 α-relaxation. In addition, two over-Tg ρI and ρII 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 γ-relaxation. However, it decreased the Ea of the β-relaxation and increased the free volume at temperatures in the vicinities of the α-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.
Asier M. Salaberria; R. Teruel-Juanes; J.D. Badia; S.C.M. Fernandes; V. Sáenz de Juano-Arbona; Jalel Labidi; A. Ribes-Greus. Influence of chitin nanocrystals on the dielectric behaviour and conductivity of chitosan-based bionanocomposites. Composites Science and Technology 2018, 167, 323 -330.
AMA StyleAsier M. Salaberria, R. Teruel-Juanes, J.D. Badia, S.C.M. Fernandes, V. Sáenz de Juano-Arbona, Jalel Labidi, A. Ribes-Greus. Influence of chitin nanocrystals on the dielectric behaviour and conductivity of chitosan-based bionanocomposites. Composites Science and Technology. 2018; 167 ():323-330.
Chicago/Turabian StyleAsier M. Salaberria; R. Teruel-Juanes; J.D. Badia; S.C.M. Fernandes; V. Sáenz de Juano-Arbona; Jalel Labidi; A. Ribes-Greus. 2018. "Influence of chitin nanocrystals on the dielectric behaviour and conductivity of chitosan-based bionanocomposites." Composites Science and Technology 167, no. : 323-330.
This paper shows the application of an innovate pedagogical approach based on the project-based learning technique, focused on the training of communication skills in the framework of a workshop of innovation in chemical engineering. Written, graphical verbal, and non-verbal communication were tackled. For that purpose, a project of technological innovation was developed by the students in teams within the specific area of chemical engineering. A professional-like environment was simulated by a final workshop where the students defenced and supported their project by using oral presentation and production of a poster and a video. Several surveys were performed before and after the project application. The final survey revealed that both students and lecturers perceived an improvement on the communication skills of the students. Moreover, both lecturers and students declared satisfaction with the methodology, recommending its application in other disciplines.
P. San-Valero; A. Robles; M.V. Ruano; N. Martí; A. Cháfer; J.D. Badia. Workshops of innovation in chemical engineering to train communication skills in science and technology. Education for Chemical Engineers 2018, 26, 114 -121.
AMA StyleP. San-Valero, A. Robles, M.V. Ruano, N. Martí, A. Cháfer, J.D. Badia. Workshops of innovation in chemical engineering to train communication skills in science and technology. Education for Chemical Engineers. 2018; 26 ():114-121.
Chicago/Turabian StyleP. San-Valero; A. Robles; M.V. Ruano; N. Martí; A. Cháfer; J.D. Badia. 2018. "Workshops of innovation in chemical engineering to train communication skills in science and technology." Education for Chemical Engineers 26, no. : 114-121.
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 valorization 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 valorization. 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 using PLA-V/R blends under similar mechanical conditions to those of virgin PLA goods. Finally, it was shown that the energetic valorization 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 valorization routes as virgin PLA and therefore could be relevant in the sustainable circular industry of bioplastics.
Oscar Gil-Castell; J. D. Badia; A. Ribes-Greus. Suitability of Blends from Virgin and Reprocessed Polylactide: Performance and Energy Valorization Kinetics. Journal of Renewable Materials 2018, 6, 370 -382.
AMA StyleOscar Gil-Castell, J. D. Badia, A. Ribes-Greus. Suitability of Blends from Virgin and Reprocessed Polylactide: Performance and Energy Valorization Kinetics. Journal of Renewable Materials. 2018; 6 (4):370-382.
Chicago/Turabian StyleOscar Gil-Castell; J. D. Badia; A. Ribes-Greus. 2018. "Suitability of Blends from Virgin and Reprocessed Polylactide: Performance and Energy Valorization Kinetics." Journal of Renewable Materials 6, no. 4: 370-382.
Oscar Gil-Castell; J.D. Badia; A. Ribes-Greus. Tailored electrospun nanofibrous polycaprolactone/gelatin scaffolds into an acid hydrolytic solvent system. European Polymer Journal 2018, 101, 273 -281.
AMA StyleOscar Gil-Castell, J.D. Badia, A. Ribes-Greus. Tailored electrospun nanofibrous polycaprolactone/gelatin scaffolds into an acid hydrolytic solvent system. European Polymer Journal. 2018; 101 ():273-281.
Chicago/Turabian StyleOscar Gil-Castell; J.D. Badia; A. Ribes-Greus. 2018. "Tailored electrospun nanofibrous polycaprolactone/gelatin scaffolds into an acid hydrolytic solvent system." European Polymer Journal 101, no. : 273-281.
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.
O. Gil-Castell; J.D. Badia; I. Ontoria-Oviedo; D. Castellano; B. Marco; A. Rabal; J.J. Bou; A. Serra; L. Monreal; M. Blanes; P. Sepúlveda; A. Ribes-Greus. In vitro validation of biomedical polyester-based scaffolds: Poly(lactide-co-glycolide) as model-case. Polymer Testing 2018, 66, 256 -267.
AMA StyleO. Gil-Castell, J.D. Badia, I. Ontoria-Oviedo, D. Castellano, B. Marco, A. Rabal, J.J. Bou, A. Serra, L. Monreal, M. Blanes, P. Sepúlveda, A. Ribes-Greus. In vitro validation of biomedical polyester-based scaffolds: Poly(lactide-co-glycolide) as model-case. Polymer Testing. 2018; 66 ():256-267.
Chicago/Turabian StyleO. Gil-Castell; J.D. Badia; I. Ontoria-Oviedo; D. Castellano; B. Marco; A. Rabal; J.J. Bou; A. Serra; L. Monreal; M. Blanes; P. Sepúlveda; A. Ribes-Greus. 2018. "In vitro validation of biomedical polyester-based scaffolds: Poly(lactide-co-glycolide) as model-case." Polymer Testing 66, no. : 256-267.
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.
C. Moliner; J. D. Badia; Barbara Bosio; E. Arato; T. Kittikorn; E. Strömberg; Roberto Teruel Juanes; M. Ek; S. Karlsson; A. Ribes-Greus. Thermal and thermo-oxidative stability and kinetics of decomposition of PHBV/sisal composites. Chemical Engineering Communications 2017, 205, 226 -237.
AMA StyleC. Moliner, J. D. Badia, Barbara Bosio, E. Arato, T. Kittikorn, E. Strömberg, Roberto Teruel Juanes, M. Ek, S. Karlsson, A. Ribes-Greus. Thermal and thermo-oxidative stability and kinetics of decomposition of PHBV/sisal composites. Chemical Engineering Communications. 2017; 205 (2):226-237.
Chicago/Turabian StyleC. Moliner; J. D. Badia; Barbara Bosio; E. Arato; T. Kittikorn; E. Strömberg; Roberto Teruel Juanes; M. Ek; S. Karlsson; A. Ribes-Greus. 2017. "Thermal and thermo-oxidative stability and kinetics of decomposition of PHBV/sisal composites." Chemical Engineering Communications 205, no. 2: 226-237.