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Copolymers from ethylene oxide (EO) and propylene oxide (PO) functionalized with glycidyl propargyl ether (GPE) are synthesized. The GPE allows further attachment of drugs but its influence on the polymeric micelle formation is unknown. In this work, the influence of the structure of these copolymers on their critical micellar concentration (CMC) in water and in the size and stability of obtained micelles is studied. For this purpose, the presence of GPE, the copolymer type (gradient or block), the EO:PO ratio and the initiator (water or ethanol) are modified. Gradient copolymers can be synthesized in a single step thanks to the different monomers reactivity, simplifying the process and obtaining similar CMC values to the block copolymers. The use of ethanol as initiator decreases the block copolymer CMC and increases the polydispersity. Besides, the presence of the GPE does not impede the micelle formation and has low effect on the copolymer CMCs. Finally, the higher the EO:PO ratio, the higher the CMC and the smaller the size of micelles. Moreover, Z-potential, DLS and HRSEM analyses show that the micelles are stable, spherical, capable to incorporate coumarin (a hydrophobic drug) and with apparent hydrodynamic sizes suitable to be absorbed by target cells., Se sintetizan copolímeros de óxido de etileno (EO) y óxido de propileno (PO) funcionalizados con glicidil propargil éter (GPE). El GPE permite una mayor unión de fármacos pero se desconoce su influencia en la formación de micelas poliméricas. En este trabajo se estudia la influencia de la estructura de estos copolímeros en su concentración micelar crítica (CMC) en agua y en el tamaño y estabilidad de las micelas obtenidas. Para ello se modifica la presencia de GPE, el tipo de copolímero (gradiente o bloque), la relación EO:PO y el iniciador (agua o etanol). Los copolímeros de gradiente se pueden sintetizar en un solo paso gracias a la reactividad de los diferentes monómeros, simplificando el proceso y obteniendo valores de CMC similares a los copolímeros de bloque. El uso de etanol como iniciador disminuye la CMC del copolímero en bloque y aumenta la polidispersidad. Además, la presencia del GPE no impide la formación de micelas y tiene un efecto bajo sobre las CMC del copolímero. Finalmente, cuanto mayor sea la relación EO:PO, mayor será la CMC y menor el tamaño de las micelas. Además,Los análisis de potencial Z , DLS y HRSEM muestran que las micelas son estables, esféricas, capaces de incorporar cumarina (un fármaco hidrofóbico) y con tamaños hidrodinámicos aparentes adecuados para ser absorbidos por las células diana.

Three different approaches to estimate the vapor pressure by thermogravimetric analyses (TGA) of commercial paraffins-based phase change materials (PCMs) have been compared. The known Langmuir vaporization relation and two additional models based on the mass transfer by molecular diffusion at isothermal and non-isothermal conditions, using the Fuller equation for estimating binary diffusion coefficients in the gas phase, were developed. The Antoine equation was used to express vapor pressure as function of temperature and the unknown constants were obtained by non-linear regression. n-Hexadecane and n-decane were used as reference compounds to estimate the deviation between experimental and predicted values. The non-isothermal model exhibited the highest accuracy for obtaining the vapor pressure and allowed to obtain boiling points and heat of vaporizations very close to those reported for the reference compounds.

Hydrophobic release agents were developed from SiO2-CH3 submicron-sized particles containing hydrophilic and hydrophobic functional groups dispersed into a vegetable oil as support. The SiO2-CH3 submicron-sized particles were synthesized by changing the molar ratio between the precursors Tetraethyl orthosilicate (TEOS) and Methyltriethoxysilane (MTES) from 0.66 to 5 (MTEOS-0.66 to MTEOS-5), being the relative amount of SiO2-CH3 quantified by FTIR technique. Mortar specimens having hydrophobic properties were manufactured using 3 wt% of the above SiO2-CH3 submicron-sized particles. Additionally, the concentration effect was studied by using MTEOS-0.66 within 3–10 wt%. The hydrophobic properties of the mortar specimens were checked by measuring the contact angle within water droplets and surface. The particle size increased with the MTES/TEOS molar ratio and according to the hydrophobic properties, the proper release agent must be synthesized by using MTEOS-2.5 dispersed into the vegetable oil and having a concentration of 3 wt%. This hydrophobic release agent led mortar surfaces with contact angles higher than 145°. Waterproofing and mechanical studies on concrete specimens allowed to conclude that this demoulding agent does not have a high penetration depth but improved the concrete waterproofing properties, without depletion in the compressive strength.

Introduction Dissociative symptoms are a type of phenomenon which is present in a wide variety of psychopathological disorders. It is therefore necessary to develop scales that measure this type of experience for therapy and research. Starting out from the bipartite model of dissociation, this study intended to adapt and validate the Detachment and Compartmentalization Inventory (DCI) in Spanish. Material and methods For this, 308 participants (268 from the community population and 40 with psychiatric pathology) completed the DCI, the Dissociative Experiences Scale (DES-II), the Somatoform Dissociation Questionnaire (SDQ20) and the Mindfulness Attention Awareness Scale (MAAS). Results The results showed that the Spanish version has a two-factor structure similar to the original version and was invariant across participants. The reliability of DCI scores was adequate and acquired evidence of validity related to other instruments. Conclusions It is concluded that the DCI is a valid scale for detecting detachment and compartmentalization dissociative experiences, both in the clinic and research.

This paper shows the elimination of arsenic (As) and hydrated silica from natural groundwater (48.63 µg L−1 arsenic, 77.5 mg L−1 hydrated silica, 0.33 mg L−1 phosphate, 5 mg L−1 sulfate, 240 mg L−1 alkalinity, 89.5 mg L−1 hardness, pH 8.44 and 450 µS cm−1 conductivity) by electrocoagulation (EC). The flow plant employed a parallel plates EC reactor in series with a flocculator-settler. Aluminum was used as the sacrificial electrode. Before the electrolysis in the flow plant, a systematic study of the aluminum dose was carried using the EC reactor adapted to a jar test. The influence of the mean linear flow velocity (1.2–4.8 cm s−1) and current density (6–9 mA cm−2) on the removal of As and hydrated silica was addressed. The residual concentration of As and hydrated silica in the flow plant was CAs = 4.2 µg L−1 and Chs = 4.5 mg L−1, respectively, at 9 mA cm−2 and 1.2 cm s−1, which agree well with that obtained in the jar test array. The residual As concentration fulfills the World Health Organization (WHO) recommendation (

Rigid PU foams are properly recycled by a single-phase glycolysis process employing crude glycerol as transesterification agent. A high pure recovered polyol (71% of purity) was obtained using a mass ratio of PU scraps to crude glycerol of 1 to 1, a reaction temperature of 190 °C and stannous octoate as catalyst in a 1.3 wt% concentration. PU foam composites containing thermoregulating microcapsules constituted by a paraffin core (Rubitherm®RT27) and a polymer shell material (LDPE and EVA) were glycolyzed, allowing to recover the microcapsules components and the polyol separately. This way, both components of the composite are recovered and can be reused in the manufacturing of new products; demonstrating for first time the viability of the chemical recycling of this kind of composites. Besides, the developed process was successfully applied for foams containing different proportions between the hard and soft segments, demonstrating its robustness. Finally, the recovered polyols were successfully employed to replace a raw rigid polyether polyol in the synthesis of new rigid PU foams. The most important physical and mechanical properties (density, maximum compressive strength and Young modulus) were maintained constant for the incorporation up to a 25 wt% of recovered polyol coming from conventional rigid PU foam scraps and up to a 37.5 wt% with the recovered polyol from rigid PU foam containing thermoregulating microcapsules. Regarding the effective thermal conductivity, it remained constant, even with 100 wt% of recovered polyol from PU scraps with thermoregulating microcapsules., Las espumas rígidas de PU se reciclan adecuadamente mediante un proceso de glucólisis de una sola fase que emplea glicerol crudo como agente de transesterificación. Se obtuvo un poliol recuperado de alta pureza (71 % de pureza) usando una relación de masa de desechos de PU a glicerol crudo de 1 a 1, una temperatura de reacción de 190 °C y octoato estannoso como catalizador en una concentración de 1,3 % en peso. Compuestos de espuma de PU que contenían microcápsulas termorreguladoras constituidas por un núcleo de parafina (Rubitherm®RT27) y un material de cubierta de polímero (LDPE y EVA) fueron glicolizados, lo que permitió recuperar los componentes de las microcápsulas y el poliol por separado. De esta forma, ambos componentes del composite se recuperan y pueden reutilizarse en la fabricación de nuevos productos; demostrando por primera vez la viabilidad del reciclaje químico de este tipo de composites. Además, el proceso desarrollado se aplicó con éxito para espumas que contenían diferentes proporciones entre los segmentos duros y blandos, demostrando su robustez. Finalmente, los polioles recuperados se emplearon con éxito para reemplazar un poliol de poliéter rígido crudo en la síntesis de nuevas espumas rígidas de PU. Las propiedades físicas y mecánicas más importantes (densidad, resistencia máxima a la compresión y módulo de Young) se mantuvieron constantes para la incorporación de hasta un 25 % en peso de poliol recuperado procedente de desechos de espuma de PU rígida convencional y hasta un 37,5 % en peso con el poliol recuperado. de espuma rígida de PU que contiene microcápsulas termorreguladoras. En cuanto a la conductividad térmica efectiva, se mantuvo constante, incluso con 100% en peso de poliol recuperado de desechos de PU con microcápsulas termorreguladoras.

The morphology and encapsulation efficiency of thermoregulating microcapsules based on a spreading coefficient theory and polar surface energy component were evaluated. For this purpose the microencapsulation of phase change materials (PCMs) with different copolymer shells and using different suspending agents by the suspension-like polymerization technique has been carried out. Contact angles and interfacial tensions were measured, and results were discussed with respect to the internal structure as well as encapsulation efficiency of the microcapsules. A core/shell structure was expected as the equilibrium morphology, whereas the experimental structure exhibited a matrix morphology. A core-shell structure was favored by increasing the polarity of the polymer and decreasing the solubility between the core and shell. The type and amount of suspending agent do not have a significant influence on the final characteristic of the microcapsules. Shells with various polarities were synthesized from styrene (S), divinylbenzene (DVB) and hexa(methacryloylethylenedioxy)cyclotriphosphazene (PNC-HEMA), and it was found that a core-shell structure was only obtained for microcapsules with a high polar surface energy component.

The recycling of any kind of plastic to convert it in valuable products is one of the main challenges of today’s society. Besides, if the recycling process is itself green, then it would be a great achievement. This paper reviews the way covered from the first attempts of reusing the polyurethane (PU) scraps as a filler for cushions to the last chemical routes employing green recycling agents. Polyurethane is the 6th most used polymer all over the world with a production of 18 millions tons per year, which means a daily production of PU specialties greater than 1 million of cubic meters, equivalent to the volume of the Empire State Building. The thermostable nature of the majority of the polyurethanes specialties has made that the preferred solution for their recycling are the chemical recycling processes. Among them, glycolysis is the one that receives a greater attention from an industrial point of view, so this review puts the spotlight on it. However, the existing reviews in literature do not paid a special attention on glycolysis and only give a superficial description of the process. Nevertheless, in the present review, the scientific literature relative to glycolysis is completely reviewed, updated and ordered according the type of PU specialty recycled. Additionally, the other main chemical recycling processes are also revisited in a more extended and deeper way than in the previous approaches to this topic. Moreover, it is crucial to take into account that some of these technologies, which were described in the literature as promising technologies at laboratory scale are now commercial processes running at industrial scale. For that reason, it is essential to remark that the present review comprises not only a detailed state of art of the scientific literature on the subject, also includes a detailed revision of the past and running on pilot plants and industrial facilities, including several patents, which has never been covered in the current literature. Moreover, this review also describes the most recent studies employing crude glycerol (biodiesel subproduct) as an economic, sustainable and environmental friendly cleavage agent, which should lead the way to the industrial implantation of split-phase glycolysis in a near future, providing high quality recovered products, susceptible of replacing raw ones in the synthesis of new PU specialties. What is more, this review intends that any reader could know and understand the reactions involved in the polyurethane chemistry and recycling, the main polyurethanes types and the fundamentals of the recycling strategies in order to comprehend what are the advantages and drawbacks of each recycling process as starting point for looking for new advantageous alternatives from an environmental, technical and economic point of view. Broader context. This paper reviews the main advances in the polyurethane (PU) recycling field, from laboratory and academia processes to pilot plant and industrial scale ones, including the most relevant patents in the subject. Opposite to other common used plastics, PUs are not polymerization but condensation polymers, synthesized from polyols and isocyanates. The wide diversity of polyols and isocyanates allows the synthesis of numerous different compounds covering a huge range of applications. As a direct consequence of their commercial success, an increasing quantity of PU waste is being disposed by landfilling in the last decades. Such waste comprises not only post-consumer products but also scrap from slabstock manufacturing, which can reach the 10% of the total foam production. However, the massive enforcement of the environmental laws is pointing out a new route in the polymer waste removal sector based in the polymer recycling, and this fact has placed the research in waste treatment as one of the most prolific topics nowadays. In fact, polymer recycling processes have experienced a growing attention from the research and industrial worlds as a direct result of the enforcement of the environmental legislations. Hence, it is essential to develop new environmental sustainable recycling processes with the aim of conserving the natural resources, reducing the amount of waste disposed in landfills and enhancing the sustainability for forthcoming generation.

A new three step process has been developed and optimized in order to demonstrate that is possible to get complete conversion of free fatty acids (FFA) into estolide esters (biolubricant), biodiesel and choline carboxylates (biosurfactants). This new approach consists in the utilization of HClO4, a cheap and industrially available strong acid, to generate the estolides followed by an esterification process with methanol in presence of a cheap ionic liquid to transform them into estolide esters and the unreacted FFA into biodiesel. A final neutralization step with choline hydroxide allowed to obtain biosurfactants. Finally, estolide esters and biodiesel were optimally split by means of molecular distillation. Both products were found to have excellent properties, fulfilling the requirements of international standards SAE J306 and EN 14214 for lubricants and biodiesel, respectively and demonstrating the industrial application of FFA as raw material to produce higher added value products.

Flexible polyurethane foams (FPUs) having polystyrene (PS) stabilized by silica gel or polystyrene-acrylonitrile (SAN) particles were synthesized employing polymer polyether polyols (PPPs). The filler and its content effect on physical, mechanical and thermal properties of FPUs were studied. The FPU thermal stability increased with PS content into PPP and no interaction filler-polymeric network was observed. Meanwhile, FPUs containing PS as filler were more thermally stable and mechanically resistant -except the elongation-than those from the commercial PPP containing SAN. Contrary to porosity and cell size, the density and hardness are function of the filler type and increase with the filler content although the hardness is practically constant from 10 wt%. Closed cell foams instead of tight foams were produced from filler contents higher than 15 wt%. Synthesized FPUs presented better hardness and density properties but worse mechanical properties than the commercial one. Finally, mechanical properties were similar than FPUs containing inorganic fillers.

This review addresses the removal of fluoride contained in different natural groundwater samples from various parts of the world using the electrocoagulation (EC) process. A detailed analysis of different metals (Fe, Al) and Al alloys used as sacrificial electrodes is carried out. The best performance in removing high concentrations of fluoride from natural groundwater (2–10 mg L−1), until fulfilling the World Health Organization (WHO) recommendation (

For the first time the functionalization via click chemistry of polylactic acid (PLA) with coumarin in supercritical conditions CO 2 has been achieved. Click reaction was performed at atmospheric pressure and supercritical carbon dioxide (scCO 2 ) for comparison being observed that is possible to obtain similar yields, higher than 95% in both cases. Once click functionalization of PLA in scCO 2 was achieved the influence of operational conditions on the polymer characteristics and in the yield was studied to get an optimized functionalization process.

Rigid polyurethane foams with up to 50 wt% of microcapsules from LDPE-EVA containing Rubitherm®RT27 were synthesized. The influence of microcapsules on the foams density, microstructure and mechanical resistance was studied. Cell size and strut and wall thicknesses were analyzed by SEM. The relationships between densities and foam microstructures with their Young's moduli and collapse stress were found by the Gibson and Ashby formulations and the Kerner equation for mechanical properties of composites. It was found a cell structure change from polyhedral closed-cells to spherical or amorphous open-cells. A good agreement between the experimental and theoretical data was observed but requiring a cell form factor. Thus, Fitting parameters confirmed the high trend of these microcapsules to be incorporated into the foam cell walls and the form factors depicted the abrupt change of cell morphology. Thus, these equations are suitable for predicting the mechanical properties of foams containing fillers of low mechanical resistance.

The synthesis of polyols from renewable resources, primarily unsaturated vegetable oils, is increasing in importance in the polyurethane market. In this work, previously epoxidized grape seed oil was transformed into an azide-functionalized bio-polyol through a ring–opening reaction with sodium azide. The effectiveness of the ring–opening reaction was confirmed by analysing the depletion of the oxirane group content in the bulk mixture and by Fourier transform infrared spectroscopy (FT-IR). A pseudo-first-order model was proposed for predicting the evolution of epoxide groups, and a good fit was obtained. The dependence of the kinetic rate constant on temperature was evaluated using the Arrhenius equation, and an activation energy value of 0.341 J/mol was obtained. A rigid polyurethane foam was synthesized from an azidified bio-polyol. No structural differences were observed between this foam and a commercial one, but a considerable improvement in thermal stability was observed.

More than 20 wt.% of grape production typically becomes waste during wine production. Grape seed oil can be extracted from this winery by-product through pressing or solvent extraction. This oil constitutes an economic alternative for valuation of by-products obtained from wine manufacturing in the Spanish region of Castilla-La Mancha. Furthermore, epoxidised vegetable oils have become one of the main intermediates for synthesizing different biomaterials. The most extended method for epoxidation is using peracids generated in situ , and many studies have investigated the influence of different variables such us reaction temperature and time, type and amount of catalyst, etc. However, a complete kinetic model able to predict reaction by-products has not yet been developed. In this work, the in situ epoxidation of grape seed oil (iodine value of 141.52 g I 2 /100 g) with aqueous hydrogen peroxide and acetic acid in presence of an acid catalyst was performed, with optimal reaction conditions of 90 °C and 60 min. Also, a general epoxidation reaction mechanism has been proposed. We propose a kinetic model able to predict the formation or depletion of different species in the process. The dependence of kinetic rate constants on temperature was evaluated through the Arrhenius equation. The activation energy for the epoxidation reaction of grape seed oil was 7.30 kcal/mol. The obtained results, particularly the proposed kinetic model, will play an important role in developing a safer and more sustainable epoxidation process, minimizing energy consumption and facilitating scale-up.

n the last years, high resilience polyurethane foams (HR foams) production has experienced an intensive growth as a consequence of their wide application field, causing an important increment of the generated waste. HR foams containing PU dispersions polyols are the last tendency in the HR foam industry, due to the improvement of the flame retardant properties and the emissions reduction of volatile compounds in comparison to the traditional graft polymeric HR polyols. In this work the extension of the glycolysis process to the recycling of this kind of foams has been carried out. Diethylene glycol (DEG), glycerol 99% PS and crude glycerol, coming from the biodiesel production, have been assayed as glycolysis agents. All of these glycolysis agents provided a split phase product with an upper phase mainly constituted by a traditional HR polyol and a bottom phase consisting of the excess of glycolysis agent and several reaction byproducts. However, the polyol content in the final product has been greater with the employment of glycerol. Moreover, flexible and rigid foams have been synthesized by using the recycled polyols or the glycolysis bottom phase, respectively. This way, it is achieved a global and sustainable recycling process for the valorization of two waste substances: the HR PU foam and the crude glycerol., En los últimos años, la producción de espumas de poliuretano de alta resiliencia (espumas HR) ha experimentado un intenso crecimiento como consecuencia de su amplio campo de aplicación, provocando un importante incremento de los residuos generados. Las espumas HR que contienen polioles de dispersión de PU son la última tendencia en la industria de las espumas HR, debido a la mejora de las propiedades ignífugas y la reducción de las emisiones de compuestos volátiles en comparación con los tradicionales polioles HR de injerto. En este trabajo se ha llevado a cabo la extensión del proceso de glicólisis al reciclado de este tipo de espumas. Se han ensayado como agentes de glicólisis el dietilenglicol (DEG), el glicerol 99% PS y el glicerol crudo, procedente de la producción de biodiesel. Todos estos agentes de glicólisis proporcionaron un producto de fase dividida con una fase superior constituida principalmente por un poliol HR tradicional y una fase inferior formada por el exceso de agente de glicólisis y varios subproductos de la reacción. Sin embargo, el contenido de poliol en el producto final ha sido mayor con el empleo de glicerol. Además, se han sintetizado espumas flexibles y rígidas utilizando los polioles reciclados o la fase de fondo de glicólisis, respectivamente. De esta forma, se consigue un proceso de reciclaje global y sostenible para la valorización de dos sustancias residuales: la espuma de PU HR y el glicerol crudo.

The reduction of the heat loss by incorporating microcapsules into rigid polyurethane (RPU) foams was studied. This way, composite foams containing between 0% and 50% by weight of microcapsules were synthesized. Microcapsules named as mSD-(LDPE·EVA-RT27) from low density polyethylene (LDPE) and ethylvinylacetate (EVA) copolymer containing Rubitherm®RT27 paraffin wax manufactured in a semi-industrial plant of spray drying were used. TES capacities of these composites were quantified by micro and macro scale, observing that phase change materials (PCMs) inside the foam were not entirely melted. Microcapsules addition promoted an increase of the incoming heat flux but lower heat losses respect to the foam without microcapsules in the transient state. Besides, the thermal conductivity of the composites increased with the content of microcapsules but this increase was also related to the non entirely melted PCM. A mathematical model was proposed in order to quantify the total amount of PCM melted during the test and it was possible to confirm that a higher temperature of 36 °C is required to reach the total melting of the PCM. It was also found that an amount of 40 wt% of microcapsules is the proper quantity to produce thermoregulating foams which combine the two advantages: energy accumulation and insulation during the transient state. Besides, the latent heat of this composite was higher than those reported in literature for thermoregulating RPU foams using MicroPCMs from melamine–formaldehyde or styrene–divinylbenzene (DVB) copolymer containing n-tetradecane or n-octadecane, respectively. Finally, if these materials are implemented in building envelopes the amount of CO 2 emitted to the atmosphere could be reduced as well as saving energy.

A synthetic strategy has been developed to create tailor-made poly(ethylene glycol) and poly(propylene glycol) copolymers functionalized with alkynyl groups that are introduced into the co-polymer chains by the addition of glycidyl propargyl ether (GPE) as co-monomer. The alkynyl-decorated copolymer obtained is used as a starter material to synthesize a drug–copolymer conjugate by copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction (click reaction). This way, hydrophobic drugs can be transformed into water-soluble compounds by improving its absorbability and bioavailability by joining them to tailor-made PEG–PPG–GPE copolymers with low polydispersity and precise molecular weight. In this work, zidovudine (AZT) drug with an azide group was chosen to be attached to the polyether chain. The chemical structure of the copolymer was characterized using infrared spectroscopy, nuclear magnetic resonance, matrix-assisted laser desorption/ionization time of flight mass spectrometry and gel permeation chromatography. Finally, 1 H NMR spectrum confirms the successful addition of the zidovudine drug to the synthesized copolymer by the click reaction.

Glycolysis is the most widely used recycling process for PU. It consists of a transesterification reaction, in which the ester group joined to the carbolinic carbon of the urethane is interchanged by the hydroxyl group of a glycol. With a large molar glycol excess condition, the reaction product splits in two phases, where the upper layer is mainly formed by the recovered polyol, with a higher purity than in the case of single phase glycolysis processes, and the bottom layer by the excess of glycolysis agent and reaction by-products. However, this huge molar excess causes an important increasing of the operation costs what makes almost impossible the implantation of industrial glycolysis plants. In this work, for the first time in literature, the feasibility of the glycolysis process of flexible PU foam scraps by means of using crude glycerol, a waste of the biodiesel production, as a novel, sustainable and economical (approximately 0.13 $/kg) transesterification agent has been demonstrated, reducing approximately in ten times the operation costs associated to the transesterification agent. Besides, crude glycerol has provided a glycolysis upper phase with a lower content of byproducts and transesterification agent than in the case of using the best transesterification agent described until this moment (DEG), as a consequence of its higher dielectric constant. Furthermore, as a result of the crude glycerol higher dielectric constant, the net yield in polyol of the glycolysis process increases due to the almost negligible presence of polyol in the bottom phase. Furthermore, once the washing of the glycolysis phases has been done, the glycolysis upper phase can be used to replace up to 25 parts per hundred (pph) of a raw flexible polyether polyol in the synthesis of new flexible PU foams. Besides, the glycolysis bottom phase can be valorized recycling it in the formulation of new PU insulating foam replacing partially the raw rigid polyether polyol. Hence, a global, sustainable and economical viable glycolysis process has been achieved by means of using two waste substances (flexible PU foam scraps and crude glycerol), obtaining valuable products of both glycolysis phases.

A new class of particulate material for the selective removal of mercury from polluted aqueous streams has been developed. The material consists in core–shell microcapsules containing a highly selective extractant agent for mercury. For this purpose, trioctylmethylammonium chloride (TOMAC) has been encapsulated within a poly(styrene-co-divinylbenzene) – P(St-DVB) – shell by suspension-like polymerisation technique. This process gave rise to a high product yield with an encapsulation efficiency of 95%. Microcapsules presented an average particle size lower than 40 μm and a TOMAC content of 37.70 wt.%. Different equilibrium experiments for mercury uptake were conducted at pH = 1 and natural pH, using synthetic solutions and natural waters from the mining district of Almaden (Spain). A mathematical model that takes into account the dissociation of mercuric chloride in solution was proposed and the solid equilibrium parameters were obtained. A good fitting between the experimental data and the model was achieved, obtaining a maximum useful capacity of 1.009 ± 0.018 eq kg−1 with a value of equilibrium constant of the monovalent specie ( HgCl 3 - ) two orders of magnitude smaller than those of the divalent HgCl 4 2 - . The mercury uptake was favoured at acid pH and low chloride concentration. Finally, it was demonstrated that using this material is possible to remove more than 92% and 99% of the metal content from the natural waters containing mercury in ng L−1 levels at natural and acid pH, respectively. The use of this new type of extractive microcapsules allows to get mercury removal levels in surface polluted waters that satisfy the mercury standard for aquatic life proposed by the USEPA (12 ng L−1) without additional pretreatments for the adjustment of the pH value.

The Eupatorieae represent nearly 10% of the Asteraceae by including about 187 genera and 2500 species. With close to 116 genera, South America is one of the richest areas of Eupatorieae diversity. The morphological variation of its genera, together with the partly incongruent circumscription of genera and subtribes yielded by morphological and molecular characters make difficult to understand the taxonomy of the tribe. In addition, clustering analyses based on morphological characters have not been carried out to explore to what extent the grouping of species obtained by these studies agrees with those provided by molecular analyses. In order to contribute to the morphological definition of the clades obtained by molecular ongoing studies, the objectives of this study are 1. To describe, characterize, compare, and assess the variability of reproductive characters in representative genera of South American Eupatorieae and, 2. To carry out a clustering analysis using reproductive morphological characters of these taxa. Additionally, we also aim to provide an even terminology of the features to be used by the specialists and detailed drawings of the reproductive structures to help to disentangle the complex morphology of Eupatorieae.A total of 123 species belonging to 42 South American genera and 14 subtribes of Eupatorieae were studied. Twenty-eight characters of involucre, receptacle, corolla, stamen, style, pappus and cypsela were morphologically and anatomically analyzed and compared. All these characters were included in the clustering analyses. The dendrogram was built using UPGMA method. Our work provides a comparative study of reproductive morphology at species level, involving 14 of the 19 subtribes of Eupatorieae. The South American studied species showed a high variability of reproductive characters. According to our statistical results, the representative genera of each Alomiinae, Ayapaninae Critoniinae, Disynaphiinae, Eupatoriinae, and Gyptidinae did not cluster together in the analysis. These outcomes agree with molecular studies that variously found these subtribes out as polyphyletic or paraphyletic. The genera of other subtribes clustered together in our statistical analysis as well as in molecular studies that found these subtribes monophyletic: Adenostemmatiinae, Fleischmanninae, and Mikaniinae. At genus rank, our results found that the sampled species of many genera clustered together, e.g., Mikania, Stevia, Barrosoa, Campoclinium, Ophryosporus, in agreement with molecular studies that found these genera monophyletic. At the same time, the species of some genera that were found para- and polyphyletic in molecular studies were obtained also in different clusters in our study, e.g., Chromolaena, Heterocondylus. In other cases, however, our results do not agree with previous molecular studies, e.g., Kaunia, Praxelis. Interestedly, our statistical analysis showed genera from different subtribes clustering together similarly to that found by molecular studies: e.g., Austrobrickellia and Stomathantes, Malmeanthus close to members of Disynaphiinae. Our results coincide with the molecular studies which obtained Stevia distantly related to Ageratum thus supporting the exclusion of Stevia from Ageratinae. All these findings should be corroborated by the addition of more species to both statistical and molecular analyses. In the light of our results, and despite some potential bias related to the sampling of species and the election and codification of characters, we can conclude that, as in recent molecular studies, the circumscription of many of the traditionally defined subtribes and many genera should be re-evaluated to describe monophyletic entities. Fil: Grossi, Mariana Andrea. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Viera Barreto, Jessica Noelia. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Plos, Anabela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Rodríguez Cravero, Juan Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Forte, Noelia Beatriz. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Gutierrez, Diego Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Sancho, Gisela. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

The use of supercritical fluids technology, in particular the use of CO2, is an important advantage over other production techniques of controlled release systems. The impregnation and foaming process can be carried out in a single step. By adjusting the conditions of pressure, temperature, depressurization time or type of polymer used, microcellular scaffolds can be obtained with desired characteristics and adapted to the patient's requirements. Moreover, it has been demonstrated that the use of polymeric solutions allows carrying out impregnation process at mild conditions. In this work, Gemcitabine impregnation in PLGA foams from polymeric solutions of ethyl lactate has been studied. The effect of polymer lactide to glycolide ratio (50:50 or 75:25), pressure (120 or 200 bar) and temperature (25 or 40 °C) were studied for three initial drug ratios (175, 105 or 35 mg GEM/g PLGA). Cell size of the foams varied between 35 μm and 158 μm, achieving an impregnation efficiency higher than 90 %. Finally, a study of the release profile of Gemcitabine in Phosphate Buffered Saline (PBS) was investigated and a mathematical modelling was carried out. In this model it was considered that the release process was divided into three different steps controlled by the external diffusion in the first place, by the internal transfer of mass in the second and then by the degradation of the polymer., El uso de la tecnología de fluidos supercríticos, en particular el uso de CO2, es una importante ventaja frente a otras técnicas de producción de sistemas de liberación controlada. El proceso de impregnación y espumado se puede realizar en un solo paso. Ajustando las condiciones de presión, temperatura, tiempo de despresurización o tipo de polímero utilizado, se pueden obtener andamios microcelulares con las características deseadas y adaptados a los requerimientos del paciente. Además, se ha demostrado que el uso de soluciones poliméricas permite llevar a cabo el proceso de impregnación en condiciones suaves. En este trabajo se ha estudiado la impregnación de gemcitabina en espumas de PLGA a partir de soluciones poliméricas de lactato de etilo. El efecto de la relación entre la lactida y el glicólido del polímero (50:50 o 75:25), Se estudiaron la presión (120 o 200 bar) y la temperatura (25 o 40 °C) para tres proporciones iniciales de fármaco (175, 105 o 35 mg GEM/g PLGA). El tamaño de celda de las espumas varió entre 35 μm y 158 μm, logrando una eficiencia de impregnación superior al 90 %. Finalmente, se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero. Se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero. Se investigó un estudio del perfil de liberación de gemcitabina en solución salina tamponada con fosfato (PBS) y se llevó a cabo un modelo matemático. En este modelo se consideró que el proceso de liberación se dividía en tres pasos diferentes controlados por la difusión externa en primer lugar, por la transferencia interna de masa en el segundo y luego por la degradación del polímero.

Jumping to conclusions (JTC) has been questioned as sufficient cognitive bias for the onset, maintenance, and severity of delusions compared to the bias of inflexibility of beliefs. The WIT (What is this?) test was designed to evaluate JTC and its capacity for classifying participants into a group of patients with active schizophrenia and a comparison group. It was also attempted to determine whether the presence/absence of answer choices, considered a measure of induced inflexibility of beliefs, influences decision-making and is related to the tendency to repeat the first decision, or spontaneous inflexibility of beliefs. The sample was made up of 160 participants, 80 patients with schizophrenia diagnosed at hospital admission and 80 healthy controls. The Beads Task and the WIT test were administered. The WIT classified the participants reasonably well (82.7%) compared to the Beads Task (86.3%). The presence of answer choices favored JTC (d = 0.33), decreasing the number of lines necessary to make a decision (d = 1.78), and influencing keeping to the original answer (d = 1.36), in interaction with the group (d = 0.42). The WIT test overcame some limitations of the Beads Task. The presence/absence of answer choices influenced decision-making and how thinking was flexibilized, more clearly in the case of controls.

Poly (lactic-co-glycolic acid) (PLGA) is a copolymer used as drug carrier in controlled release systems as microparticles or scaffolds. Foamed structures are industrially obtained by injecting gas at temperatures above the melting point of the polymer that may promote PLGA degradation. High temperatures are avoidable in this foaming process if a polymer dissolution is used. Ethyl acetate and ethyl lactate are suitable solvents for the PLGA since the polymer is easily solubilised, is environmentally friendly and highly recommendable for medical purposes. CO2 is proposed as antisolvent because is environmentally benign, non-flammable and non-toxic. The knowledge of the solubility of these solvents in CO2 is essential to find the most appropriate working conditions for the foaming process. In this work, the solubility of ethyl acetate and ethyl lactate in CO2 in the presence of different initial concentrations of PLGA has been studied at 298.15 K and at pressures up to 150 bar using a high-pressure variable volume view cell., El poli (ácido láctico-co-glicólico) (PLGA) es un copolímero que se utiliza como transportador de fármacos en sistemas de liberación controlada como micropartículas o andamios. Las estructuras espumadas se obtienen industrialmente mediante la inyección de gas a temperaturas superiores al punto de fusión del polímero que pueden promover la degradación del PLGA. Las altas temperaturas se pueden evitar en este proceso de formación de espuma si se utiliza una disolución de polímero. El acetato de etilo y el lactato de etilo son disolventes adecuados para el PLGA ya que el polímero se solubiliza fácilmente, es respetuoso con el medio ambiente y muy recomendable para fines médicos. El CO2 se propone como antidisolvente porque es ambientalmente benigno, no inflamable y no tóxico. El conocimiento de la solubilidad de estos disolventes en CO 2es fundamental encontrar las condiciones de trabajo más adecuadas para el proceso de espumado. En este trabajo se ha estudiado la solubilidad del acetato de etilo y lactato de etilo en CO 2 en presencia de diferentes concentraciones iniciales de PLGA a 298,15 K y presiones de hasta 150 bar utilizando una celda de visión de volumen variable de alta presión.

The objective of this study was to evaluate the feasibility of supercritical oil extraction from Jatropha curcas L (JCL). The influence of the operating conditions on oil yield, free fatty acid content of JCL oil, and oil quality was examined, which included pressure, temperature, particle size, and percentage of hull. The conditions for the fractionation of fatty acid were selected to obtain good-quality oil for biodiesel production. Finally, an experiment was conducted under different conditions in which the greatest amount of free fatty acids (FFA) (26.3 wt.%) was extracted during the first fractions and then the pressure was increased to achieve good oil removal (91 wt.% oil yield) performance with low content of free fatty acids (1 wt.%). This study has a promising role to fill as a more cost-effective processing technology, and it is not necessary to carry out a degumming, esterification and dehydration in the oil of the last fractions. Furthermore, all the phorbol ester was removed from the oil by conducting a supercritical extraction using CO 2 .

A new thermoregulating material containing the commercial paraffin Rubitherm®RT27 stabilized by SiO2 with a polymeric shell from polystyrene–divinylbenzene (Polymeric-SiO2-PCMs) was incorporated into gypsum up to a 15 mass ratio respect to the initial hemihydrate in order to develop building materials with a high thermal energy store (TES) capacity. The effect of this material on the gypsum crystals and the main physical, thermal and mechanical properties were studied and compared to those caused by another three kinds of thermoregulating materials. Polymeric-SiO2-PCMs presented the lowest agglomeration and therefore, the best distribution into the gypsum pores. As expected, the thermoregulating effect of the PCM improved the thermal properties of the gypsum since, the higher the microcapsules content, the higher the equivalent heat capacity (cp) and the accumulated heat power (qacc). Considering a conversion of 100% of the accumulated heat into electricity savings, the addition of a 15% of microcapsules respect to the hemihydrate allowed to save 10.20 kW h/m3 and, consequently, reduced the CO2 emissions in a 1.26 kg of CO2 per operating cycle. Besides, the addition of the Polymeric-SiO2-PCMs reduces the gypsum density, but it is always higher than 600 kg/m3, as required by the European regulation EN 13279-2. The thermal conductivity (k) is also reduced by the microcapsules addition but for the case of a content of 15%. On the other hand, the porosity is barely affected just varying always less than a 3.5%. Finally, despite of the fact that the Polymeric-SiO2-PCMs addition reduces the mechanical properties, all the developed materials satisfied the mechanical European regulation EN 13279-2 which limits the minimum compression and flexural strengths of gypsum composites for building construction to 2 and 1 MPa, respectively. The thermal and mechanical properties of the composite gypsums containing Polymeric-SiO2-PCMs are better than those obtained for the rest of the studied thermoregulating materials.

Nowadays polymer recycling processes are an urgent task due to the huge quantity of wastes that are generated. Polyurethane is the 6th polymer most used all over the world with a production of approximately 12 million tons per year. Flexible foams represent about the half of polyurethane total production and among them conventional polyurethane flexible foams mean the 80%. This type of foams are synthesized or using only a flexible polyether polyol or a mix of a flexible polyether polyol with a polymeric polyol. A series of works about the glycolysis of flexible foams synthesized only with flexible polyether polyol have been carried out by our research group. In this work, for the first time in literature, a detailed study of the glycolysis of flexible polyurethane foams containing polymeric polyol has been accomplished. It has been demonstrated that is possible to carry out the glycolysis of these foams using similar reactions conditions determined for the glycolysis of conventional flexible polyurethane foams synthesized only with flexible polyether polyol. Furthermore, after a proper treatment process of the recovered polyol, flexible polyurethane foams have been synthesized using mixtures of raw polyol with the recovered one.

La publicación de la quinta edición del DSM ha avivado un debate iniciado tiempo atrás, desde el anuncio de los cambios en los criterios de diagnóstico propuestos por la APA. En este artículo se analizan algunas de estas modificaciones. Se plantean aspectos interesantes y acertados, como la inclusión de la dimensionalidad tanto en las clases diagnósticas como en algunos trastornos, la incorporación de un espectro obsesivo-compulsivo o la desaparición de los subtipos de esquizofrenia. También se analizan otros aspectos más controvertidos como la consideración del síndrome de psicosis atenuada, la descripción de un trastorno depresivo persistente, la reordenación en trastornos de síntomas somáticos los clásicos trastornos somatoformes, o el mantenimiento de los tres grandes grupos de trastornos de la personalidad,siempre insatisfactorios, junto con un planteamiento anunciado, pero marginal, de la perspec-tiva dimensional de las alteraciones de la personalidad. La nueva clasificación del DSM-5 abrenumerosos interrogantes acerca de la validez que se pretende mejorar en el diagnóstico, enesta ocasión, asumiendo un planteamiento más cercano a la neurología y la genética que a lapsicopatología clínica., The publication of the fifth edition of the DSM has intensified a debate begun some time agowith the announcement of the changes in diagnostic criteria proposed by the APA. This article analyzes some of these modifications. Some interesting points where it is right, such as the inclusion of dimensionality in both diagnostic classes and in some disorders, the inclusion of an obsessive-compulsive spectrum, and the disappearance of subtypes of schizophrenia. It also analyzes other more controversial points, such as the consideration of the attenuated psychosis syndrome, the description of a persistent depressive disorder, reorganization of the classic somatoform disorders as somatic symptom disorders, or maintenance of three large clusters of personality disorders, always unsatisfactory, along with an announced, but marginal, suggestion of the dimensional perspective of personality impairments. The new DSM-5 classification opens many questions about the diagnostic validity which it attempts to improve, this time taking an approach nearer to neurology and genetics than to clinical psychology.

An environmentally friendly technology to recycle Polystyrene (PS) wastes from a solution of p-Cymene using CO 2 as antisolvent was proposed. In this process, the study of equilibrium of the ternary mixtures CO 2 /p-Cymene/Polystyrene is crucial, and particularly, the solubility of p-Cymene in CO 2 and the sorption of CO 2 in the solution are the key factors since the recovered polymer should be precipitated while the solvent should be fully solubilized in CO 2 . In this work, the effect of pressure (50–100–150 bar), temperature (25–30–40 °C) and polymer concentration (0.05–0.80 g PS/ml p-Cymene) on the solubility of p-Cymene and CO 2 were studied to determine the most suitable conditions to perform the precipitation of Polystyrene. The experimental data were correlated as a function of density and polymer concentration according to modifications of well-known semi-empirical expressions (Chrastil's equation and Dual-Mode model). The optimum conditions to carry out the precipitation process of Polystyrene were calculated from the application of the fitted parameters obtained from the previous proposal. The most suitable conditions to precipitate Polystyrene from its solution in p-Cymene were reached at high values of density, it means, high pressure, low temperature and moderated concentration.

Smart gypsum composites were manufactured by adding different kinds of microcapsules containing phase change materials (PCMs) in order to develop building materials with high thermal energy storage (TES) capacity useful for being applied in high comfort constructive systems. The physical, thermal and mechanical properties of these composites such as density, porosity, thermal stability, thermal conductivity (k), equivalent heat capacity (cp), the accumulated heat power (qacc) and the maximum compressive strength were studied. Results showed that the higher the microcapsules content, the lower the density and k and the higher the cp and qacc, due to the PCM action. Besides, the addition of 15 wt% of microcapsules respect to the hemihydrate would allow to save 4.5 kWh of energy per operating cycle in a standard room covered with 1 m3 of this gypsum. This energy is equivalent to the energy spent by three incandescent light bulbs of 60-W kept on all the day and a reduction of 1.395 kg of CO2 emissions to the atmosphere. The addition of these thermoregulating materials to gypsum decreases their compressive strength but all the developed materials satisfied the Spanish mechanical regulations for gypsum as building material, being possible to increase the total amount of added microcapsules.

The foaming process has been traditionally performed at high temperature because the CO 2 and the polymer should behave as a homogeneous solution. The addition of a solvent could avoid the high working temperature while the homogeneity is ensured. Among the terpene oils, limonene outlines as a good candidate to carry out the dissolution of polystyrene because it respects the green chemistry principle, it is highly soluble in CO 2 and very compatible with the polymer. The sorption of CO 2 is the first step of the foaming process. The presence of the terpene oil enhances the solubility of the gas which is solubilized in the Polystyrene as well as in the limonene. During the foaming process, many parameters can be tuned to customize the foams. In this work, a fractional factorial design of experiment was proposed to determine the effect of pressure, temperature, concentration of the solution, contact time and vent time over the diameter of cells, its standard deviation and the cells density. The proposed foaming process can be simply performed at mild pressure and temperature thanks to the presence of the solvent. The results showed that the most suitable conditions to foam polystyrene from limonene solutions are 90 bar, 30 °C, 0.1 gPS/ml Lim, 240 min contacting and 30 min venting. Finally, the samples were characterized to determine the amount of residual solvent, their glass transition and degradation temperature checking that the foams presented around 5% of solvent traces but did not show any evidence of degradation.

We demonstrate the use of a quartz crystal viscometer to determine the viscosity of solutions of polystyrene in limonene in the presence of high pressure carbon dioxide. These measurements were determined up to 50 bar in the range of temperature from 20 to 40 °C and at 0.025, 0.05, 0.1, 0.2, 0.3 and 0.4 g PS per ml of limonene. The selected variables of study (pressure, temperature and concentration) were statistically significant over the range of viscosity studied. The viscosities of the solutions at all loadings were found to decrease with increasing temperature and pressure while the plastising effect of CO 2 prevailing over the hydrostatic pressure applied by the gas. The flow activation energies of the system were obtained from an Arrhenius fitting of the experimental data reaching a maximum of 40 kJ/mol. An empirical model correlating the viscosity of the mixtures to pressure and temperature was developed in order to interpolate and extrapolate in the study region or in a range close to the working limits. Finally, the viscosity data were used to determine the solvent quality and to quantify the demixing points of the mixtures.

The development of new polyurethane coatings with enhanced flame retardant properties based on the phosphorylated polyols is explored. The incorporation of phosphorus into the polymer molecular structure took place by reacting polymeric MDI with polyether polyols based on an alkoxylated glycerol phosphate initiator. The structure of the coatings was confirmed by FT-IR spectra. The thermal stability and flame retardant properties of the coatings were characterized using TGA, TGA-MS. LOI test, cone calorimetry, SEM microscopy and EDAX analysis. The results have highlighted the importance of the phosphorus chemical environment and its influence on the thermal degradation and oxidation of the polyol under different atmospheres.

Dissolution with terpenic solvents is presented as an alternative and original route to recycle Polystyrene wastes at room temperature. Limonene was the chosen solvent to carry out the dissolution process because it presents high compatibility with Polystyrene besides being natural, non toxic and relatively low cost. The solvent removal is possible thanks to supercritical CO 2 since it provides high solubility of Limonene and complete PS insolubility at moderated pressures and temperature. In order to determine the proper working conditions to conduct the precipitation of the polymer, accurate knowledge of the phase equilibrium for mixtures of carbon dioxide, Limonene and Polystyrene should be known. In this work, the solubility of Limonene in the ternary system CO 2 /Limonene/Polystyrene was determined. The phase equilibrium experiments were conducted in a variable-volume view cell employing the static method. These experiments were carried out in the temperature range of 298.15–313.15 K, at pressures up to 15 MPa and in the concentration range of 0.05–0.80 g PS/ml Limonene. Initially the binary systems were studied by means of equations of state: Peng–Robinson in the case of CO 2 /Limonene and Sanchez–Lacombe in the case of Limonene/PS and CO 2 /PS. Predicted data were collected together with the experimental to check the agreement and to determine the limits of the ternary system formed by CO 2 –Limonene–PS. It is indispensable to determine the behaviour of the ternary system to know completely the fluid phase equilibrium. The results indicate that the solubility of Limonene in the vapour phase is favoured by high pressure and temperature as well as low concentration.

The low thermo-oxidative properties of PU foams somewhat limits their practical application, particularly as heat sensitive materials. The introduction of a covalently linked flame retardant organophosphonate ester into the PU foam was achieved using the CuAAC ‘click’ reaction of an alkyne-polyol and azidoalkylmonophosphonate. These functionalised materials were prepared in four steps: first, a number of azidoalkyl monophosphonate compounds were formed via nucleophilic substitution of bromoalkylphosphonates with NaN3; next, polyols bearing terminal alkyne groups were prepared by anionic ring opening copolymerization between propylene oxide and glycidyl propargyl ether; followed by ‘clicking’ the azidoalkylphosphonate to the polyol and finally, synthesis of the PU foam with 2.4 wt% of “click-polyol”. The functionalised PU foam demonstrated a well-formed polyhedral cell structure and an increase in the fire resistance, according to the SEM and thermogravimetric analysis, respectively. Even after thermal treatment at 400 °C, the new PU foam material displayed enhanced flame resistant properties by forming a char layer on the surface of the polymer, whilst maintaining its polyhedral structure.

Supercritical fluid technology was tested to produce biodegradable porous probes impregnated with an antineoplasic drug that once conformed could be used as scaffolds as an alternative to traditional methods of preparation. The impregnation of 5-fluorouracil, a chemotherapy agent, was carried-out at the same time to the foaming process in a one-shot procedure. The polymer foam probes were based on d , l -lactide and glycolide and prepared varying the operating conditions. The homopolymer poly( d , l -lactide) and the copolymer poly( d , l -lactide-co-glycolide) were used as base materials. The influence of stirring speed and venting rate on the drug loading and the average pore size were evaluated in order to optimize the impregnation process. Venting rate revealed to be the most important factor affecting the probes pore size and their morphology. Slow venting rates should be used to promote small pores in order to retard the drug release from the polymeric matrix. Fast stirring rates improves the impregnation process because favours the contact between supercritical CO 2 and the swelled polymer. The presence of glycolide enhanced the mechanical strength of the foam preventing pore collapse. This fact together with the possibility of regulating the rate of the scaffold degradation and the kinetics of drug release makes the usage of the copolymer more attractive for a further medical application.

The economic feasibility of supercritical processes by a business plan strategy has been investigated using as a model the continuous CO 2 fraction of liquid capsicum oleoresin. First, the SWOT matrix of the process has been determined from internal and external analyses, revealing the interest of the process for industrial application and the necessity of a detailed economic analysis. In a second step, the investment and financial analyses have been determined for two different scenarios related to the location of the plant, i.e. within the facilities of the university on the one hand, or as an enlargement of an existent paprika factory, on the other. In this second scenario the pay-back period for the capital investment is 3.5 years and the margin of safety ratios over the accounting period 2011–2015 varies in the interval 2–3, indicating the healthy situation of the project. Finally, sensitivity analysis extends the robustness of the economic evaluation described in this work by revealing slight differences in payback periods and financial ratios when underestimations of 10% of the fixed capital investment and operating costs and of the 5% interest rate are considered. The presented results conclude the economic feasibility of this supercritical process and extend conventional economic analysis by the use of a business plan strategy.

Interfacial tension (IFT) is a key physicochemical parameter that plays an important role during the foaming process of polymers. The pendant droplet method is a useful technique to determine the IFT, which has been studied at mild working conditions (0–9 MPa, 303.15–313.15 K). In this work, limonene and cymene were used as solvent to prepare polymer dissolutions and observe their influence on the experimental IFT measurements. Also, the effect of CO2 on the glass transition of polystyrene and polystyrene dissolutions was studied in order to select the most suitable temperature to carry out the experiments. The behaviour of the polystyrene dissolution in the presence of CO2 can be considered similar to molten polymer. A controlled foaming of the polystyrene-solvent mixtures can be easily carried out at moderate temperature and pressures by exploiting the advantages that provide the solvent, obtaining completely “dried” PS foams.

Several catalysts based on tin compounds (tin(II) acetate, tin(II) chloride, tin(II) 2-ethylhexanoate and tin(II) stearate) have been tested in transesterification and esterification reaction in order to treat acid vegetable oils. All of them, except tin(II) stearate, showed good catalytic activity in transesterification reaching a methyl ester content higher than 96.5 wt. % in 24 h. When catalysts were tested in the simultaneous trans- and esterification of acid oil, the formation of water deactivated the catalyst tin(II) 2-ethylhexanoate. Best results were obtained with tin(II) acetate (methyl ester content, 96.6 wt. % at 150 °C and 3 h). Finally, the reusability of tin(II) acetate was studied, because it could be recovered from the reaction by filtration.

The general purpose of polyurethane chemical recycling is to recover constituent polyol. Among the suitable processes, glycolysis, and specially glycolysis in two-phases is the one that allows recovering the polyol with the highest quality in comparison to single-phase processes. Recently stannous octoate has been stated as the catalyst that provides the fastest decomposition rate and the one that allows obtaining a recovered polyol with similar characteristics to fresh polyol. In this work a study of the main reaction parameters has been carried out. Optimal catalyst concentration, ratio of glycolysis agent to treated PU foam and optimal reaction temperature have been determined.

A micellar electrokinetic chromatography (MEKC) method was developed for the determination of paclitaxel, morphine and codeine in human urine from patients under cancer treatment. The background electrolyte consisted of a borate buffer (pH 9.2; 20 mM) with sodium dodecyl sulfate (60 mM) and 5% MeOH. The applied voltage was 25 kV, temperature was 20 °C and the sample injection was performed in the hydrodynamic mode. All analyses were carried out in a fused silica capillary with an internal diameter of 75 μm and a total length of 57 cm. The detection of target compounds was performed at 212 nm. Under these conditions, a complete separation of paclitaxel, morphine and codeine was achieved in less than 15 min. According to the validation study, the developed method was proved to be accurate, precise, sensitive, specific, rugged and robust. This method was applied to the analysis of six urines samples from different cancer patients undergoing treatment with paclitaxel or/and codeine. In all the urine paclitaxel determination were done.

Supercritical fluid technology was studied as an alternative technology for the production of biodegradable polymer foamed scaffolds with applications in tissue engineering. The probes produced were based on d , l -lactide and glycolide and a non-steroidal drug, indomethacin, was impregnated simultaneously in the obtained probes in a one-step process. It was found that the copolymer-based foams were desirable respect to the homopolymer-based ones concerning the subsequent drug release applications. They exhibited enhanced mechanical strength, preventing pore collapse and favoring the subsequent drug release. Fast stirring rates favored the impregnation process and a slow rate of depressurization was also desirable because promoted the formation of small size pores that retard the release of the indomethacin from the polymeric support and the homogeneous drug distribution into the polymer matrix.

In this paper the use of supercritical CO2 technology is studied as a means of streamlining olive husk extraction so as to obtain extracts with a high content of valuable compounds and without any residual solvent. Response surface methodology (RSM) was used to evaluate how pressure (25–35 MPa) and temperature (313–333 K) affected oil yield and the extract quality (expressed in terms of tocopherol, carotenoids and chlorophyll concentration). The effect of using ethanol as a cosolvent was also evaluated. Kinetic parameters were obtained for their use in the design and optimization of the extraction process and for scale-up steps in particular. Optimal extraction conditions were determined taking both maximum yield and recovery criterion into account. In these conditions the valuable compounds were from two to four times more concentrated than in classical hexane extraction.

Polystyrene microcapsules containing Rubitherm® RT31 were prepared by suspension-like polymerization method using different suspension stabilizers. These microcapsules could be applied to the textiles in a variety of processes to improve thermal comfort of end-use products. The effects of polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), arabic gum and gelatin as suspension stabilizers were investigated regarding thermal properties, particle size distributions, morphologies using differential scanning calorimetry, scanning electron microscopy and laser light scattering analyses. The type of suspension stabilizer had a significant effect on the particle size distribution and the morphology of the synthesized microcapsules. Spherical and regular microcapsules with smooth surface were obtained using PVP and gelatin as suspension stabilizers. However, with arabic gum and PVA irregular particles with rough surface were produced due to the interfacial tension between the polymer and the aqueous phase was close to that between PCM and polymer contacted the aqueous phase. On the other hand, the lowest average particle size in number and in volume was obtained for polyvinylpyrrolidone. The highest amount of Rubitherm® RT31 encapsulated was 67.9 wt.% for arabic gum.

A new sulfonated material from styrene–divinylbenzene copolymer, P(St–DVB), containing di(2-ethylhexyl)phosphoric acid (DEHPA) that combines the advantages and capabilities of the ion exchange and the solvent extraction technologies has been developed. Microcapsules with a DEHPA content of 34.86 wt.%, an average particle size of 340.83 μm and an equivalent thickness shell of 22.4 μm were prepared by suspension-like polymerization technique and further sulfonated. The influence of the chemical nature and properties of the suspending agent on the microcapsules characteristics were studied. The polluting potential of the wastewater generated in the encapsulation process with the different suspending agents was also evaluated. Arabic gum:PVA showed to be the best combination of suspending agent for the process. The incorporation of sulfonic groups to the polymeric network turn the hydrophobic nature of the particle into another with hydrophilic character. The increase of the sulfonation time from 10 to 30 min promoted the cracking of the microcapsules (from 24.49 to 75.36 wt.%). A total ion exchange capacity of 3.56 meq g−1 was achieved. The large ion exchange rate and capacity observed confirm that the sulfonation of the shell makes easier the mobility of the metallic ions from the liquid phase to the extractant agent phase through the shell. It was also observed that the presence of DEHPA into the microcapsules makes them more selective than a conventional ion exchange material.

Oleoresin Capsicum is one of the most important sources of natural colorants with a lot of applications in food industry due to its carotenoids concentration. With high content of lipid matter and a noticeable amount of capsaicinoids, Oleoresin Capsicum can also be used in pharmaceutical industry or for self-defense sprays. In this work, the phase equilibrium of Oleoresin Capsicum in supercritical carbon dioxide was measured by a recirculation method at pressures between 90 and 315bar and temperatures of 314.7, 326.4 and 337.8K. The experimental data were correlated using Soave-Redlich-Kwong (SRK) equation of state with Mathias-Klotz-Prausnitz as mixing rule, and binary interaction parameters were obtained. Moreover, the prediction of the pseudo-binary system CO2/Oleoresin Capsicum was carried out with the Group Contribution Equation of State (GC-EoS), using the set of binary group parameters established in a previous work. For all isotherms studied, the solubility of Oleoresin Capsicum in the gaseous phase and that of CO2 in the liquid phase increases with an increase in pressure. Comparison between experimental data and those correlated by SRK or predicted by GC-EoS, shows that SRK correlation produced better fittings of the experimental data. Nevertheless, the importance of data predicted by GC-EoS is based on the possibility to obtain an approximation to the thermodynamic behaviour of the real systems without the necessity of experimental data.

Oleoresin capsicum (ORCap) is the commercial liquid product obtained after the solvent extraction of peppers (Capsicum annuum L.). With high content of lipid matter and a noticeable amount of pigments, such as capsaicinoids and carotenoids, oleoresin capsicum is usually used in food industry. Besides, if an enrichment of carotenoids and capsaicinoids is reached, many applications in pharmaceutical and cosmetic industry can be covered by the products obtained. In this work, the fractionation of oleoresin capsicum using supercritical CO2 countercurrent extraction was studied to obtain an extract enriched in capsaicinoids and a raffinate enriched in carotenoids. Moreover, the separation column was designed. Phase equilibrium of the system CO2-oleoresin capsicum was determined along the interval of temperature (314-338K) and pressures (90-310bar), and samples of both phases were analytically characterized. Due to the inadequacy of the binary approach to study the separation problem, a pseudoternary approach was selected and oleoresin capsicum was described by two pseudocompounds according to its distribution coefficients. At 337.8K and 206bar a maximum selectivity of 5.6 between the pseudocompound enriched in capsaicinoids and the pseudocompound enriched in carotenoids was obtained. This fact showed that countercurrent gas separation could be employed and could be economically interesting. The column design was performed according to two different short-cut methods and different separation parameters, such as the number of theoretical stages (n th), the reflux ratio (ν) and the solvent-to-feed ratio (S/F), were calculated. Janecke method presented the best result according to the change in composition along the separation column. Finally, the minimum diameter of the column to be designed, which is necessary to avoid flooding conditions, was also calculated for different packings.