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  • Effect of the thermoforming process variables on the sheet friction coefficient

     Morales, Rosa Amalia; Candal Pazos, Maria Virginia; Santana Pérez, Orlando Onofre; Gordillo Aubert, Antonio; Salazar, Rubén
    Materials and design
    Date of publication: 2014-01
    Journal article

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    The objective of this work was to obtain, through a simple experimental assembly, the real influence of the friction and process conditions in the assisted thermoforming process. The use of simulation tools to optimize this process requires the knowledge of the sheet-plug system friction coefficient [µ], the used temperature and velocity conditions, and due to that, the software does not have a wide database. For this, the users suppose µ with the previous known difference between the simulated and the experimental data. For this reason, the obtaining of µ may allow to achieve more accurate simulations. In this work, a modified pendulous impact in Izod geometry was used to the measurements. The µ increased with the sheet temperature. On the other hand, it was not possible to detect a significant µ variations regarded with the plug material. © 2013 Elsevier Ltd.

  • Enhanced general analytical equation for the kinetics of the thermal degradation of poly(lactic acid) driven by random scission

     Carrasco, Félix; Perez Maqueda, L.A.; Sanchez Jimenez, P.E.; Perejón, A.; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Polymer testing
    Date of publication: 2013-08
    Journal article

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    An enhanced general analytical equation has been developed in order to evaluate the kinetic parameters of the thermal degradation of poly(lactic acid) (PLA) at various linear heating rates and at constant rate conditions. This improvement consisted of replacing the n-order conversion function by a modified form of the Sestak-Berggren equation f(a) = c(1-a)nam, which led to better adjustment of experimental data, and also adequately represented the conventional mechanisms for solid-state processes. The kinetic parameters so obtained have been compared to those determined by conventional differential and isoconversional methods. Given that the thermal degradation of PLA has been argued to be caused by random chain scission reactions of ester groups, the conversion function (a) = 2(a1/2-a), corresponding to a random scission mechanism, has been tested.

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    Caracterización mecánica, térmica y a fuego de aerogeles arcilla/polímero modificados con partículas  Open access

     Sanchez Soto, Miguel Angel; Wang, Liang; Martinez Benasat, Antonio; Velasco Perero, Jose Ignacio; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Congreso Nacional de Materiales Compuestos
    Presentation's date: 2013-07-03
    Presentation of work at congresses

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    Los aerogeles son una clase de materiales que se caracteriza por su extrema ligereza y alto contenido de aire. En este trabajo se han preparado diferentes aerogeles polímero/arcilla (PVOH/Na+-MMT) mediante un proceso simple de congelación y liofilización. Mediante esta técnica se han preparado aerogeles modificados conteniendo diferentes agentes ignifugantes en forma de partículas. La adición de dichos agentes causó un ligero incremento de la densidad aparente. Las propiedades mecánicas en compresión tanto a baja como a alta velocidad en general se vieron ligeramente reducidas debido a una menor unión entre el polímero y la arcilla. La excepción fue la muestra modificada con Al(OH)3 que incrementó la rigidez de los compuestos y la tensión a máxima deformación. En cuanto a las propiedades térmicas, la presencia de polifosfato de amonio (APP) o de silica gel (SG) redujo notablemente la velocidad de descomposición de los aerogeles en el rango de temperaturas entre 250ºC y 650ºC, sin embargo, la temperatura de inicio de descomposición no se vio sensiblemente alterada. El comportamiento a fuego se analizó mediante calorimetría de cono y los resultados han indicado que tanto la presencia de Al(OH)3 como de APP retardan la combustión del sistema y reducen la tasa de liberación de calor.

    Los aerogeles son una clase de materiales que se caracteriza por su extrema ligereza y alto contenido de aire. En este trabajo se han preparado diferentes aerogeles polímero/arcilla (PVOH/Na+-MMT) mediante un proceso simple de congelación y liofilización. Mediante esta técnica se han preparado aerogeles modificados conteniendo diferentes agentes ignifugantes en forma de partículas. La adición de dichos agentes causó un ligero incremento de la densidad aparente. Las propiedades mecánicas en compresión tanto a baja como a alta velocidad en general se vieron ligeramente reducidas debido a una menor unión entre el polímero y la arcilla. La excepción fue la muestra modificada con Al(OH)3 que incrementó la rigidez de los compuestos y la tensión a máxima deformación. En cuanto a las propiedades térmicas, la presencia de polifosfato de amonio (APP) o de silica gel (SG) redujo notablemente la velocidad de descomposición de los aerogeles en el rango de temperaturas entre 250ºC y 650ºC, sin embargo, la temperatura de inicio de descomposición no se vio sensiblemente alterada. El comportamiento a fuego se analizó mediante calorimetría de cono y los resultados han indicado que tanto la presencia de Al(OH)3 como de APP retardan la combustión del sistema y reducen la tasa de liberación de calor.

  • Effect of the unidirectional drawing on the thermal and mechanical properties of PLA films with different L -isomer content

     Velázquez Infante, Julio César; Gámez Pérez, José; Franco Urquiza, Edgar Adrian; Santana Pérez, Orlando Onofre; Carrasco, F; Maspoch Ruldua, Maria Lluïsa
    Journal of applied polymer science
    Date of publication: 2013-02-15
    Journal article

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    This work simulates the thermoforming process of two different L-isomer content PLA grades (95.6 and 98%), studying the influence on the induced morphology and the variation in the thermal and tensile properties. The thermoforming process was simulated with uniaxial tensile tests performed at different temperatures and strain rates, reporting the tensile behavior before, during, and after the test. The resulting structural changes were analyzed by wide-angle X-ray scattering and Fourier transformed infrared spectroscopy. Thermal characterization was carried out with differential scanning calorimetry and dynamomechanical thermal analysis. The results showed that, regardless the L-isomer content, drawing at 70°C produced a stable mesomorphic phase that showed greater tensile properties than the original films. This mesomorphic phase, indeed, could be reordered into a crystalline structure under mild annealing conditions (5 min/75°C), if compared with those needed for similar amorphous PLA specimens (60 min/120°C), thus providing a processing opportunity for obtaining thermally stable PLA products at temperatures above 100°C.

  • Halogen-free flame retardant polyolefin foams

     de Redondo Realinho, Vera Cristina; de Sousa Pais Antunes, Marcelo; Santana Pérez, Orlando Onofre; Velasco Perero, Jose Ignacio
    International Conference on Foam Materials & Technology
    Presentation's date: 2012-09-12
    Presentation of work at congresses

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  • Sheets of branched poly(lactic acid) obtained by one step reactive extrusion calendering process: Melt rheology analysis

     Cailloux, J.; Santana Pérez, Orlando Onofre; Franco Urquiza, Edgar Adrian; Bou Serra, Jorge; Carrasco, F; Gámez Pérez, José; Maspoch Ruldua, Maria Lluïsa
    Express polymer letters
    Date of publication: 2012-03
    Journal article

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  • Effect of the strain rate and drawing temperature on the mechanical behavior of EVOH and EVOH composites

     Franco Urquiza, Edgar; Gámez Pérez, José; Velázquez Infante, Julio César; Santana Pérez, Orlando Onofre; Martinez Benasat, Antonio; Maspoch Ruldua, Maria Lluïsa
    Advances in polymer technology
    Date of publication: 2012-02-27
    Journal article

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    The effect of the strain rate and draw temperature on the mechanical behavior of ethylene vinyl alcohol (EVOH) and EVOH composites was analyzed. When EVOH is stretched at moderate strain rates, evidence of strain-induced crystallization and recrystallization was observed. Higher strain rates produced less structural variation because the homogeneous flow of the chains and the crystalline perfection are restricted due to the rapid drawing. In reference to the drawing temperature, EVOH showed a diffusive yielding, and the mechanical parameters were reduced due to the softening of the crystalline region. For EVOH composites, the filler hinders the molecular mobility, causing an increase in the strength and restricting the plastic flow. However, the higher temperature, higher molecular mobility, and ductility are not so affected by the filler content

    The effect of the strain rate and draw temperature on the mechanical behavior of ethylene vinyl alcohol (EVOH) and EVOH composites was analyzed. When EVOH is stretched at moderate strain rates, evidence of strain-induced crystallization and recrystallization was observed. Higher strain rates produced less structural variation because the homogeneous flow of the chains and the crystalline perfection are restricted due to the rapid drawing. In reference to the drawing temperature, EVOH showed a diffusive yielding, and the mechanical parameters were reduced due to the softening of the crystalline region. For EVOH composites, the filler hinders the molecular mobility, causing an increase in the strength and restricting the plastic flow. However, the higher temperature, higher molecular mobility, and ductility are not so affected by the filler content.

  • Chain architecture modifications of Poly(Lactic Acid) by reactive extrusion

     Santana Pérez, Orlando Onofre; Callioux, Jonathan; Franco Urquiza, Edgar Adrian; Bou Serra, Jorge; CARRASCO, FELIX; Gámez Pérez, José; Maspoch Ruldua, Maria Lluïsa
    European Polymer Congress
    Presentation's date: 2011-06-26
    Presentation of work at congresses

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    Fractura postcedencia de polímeros  Open access

     Maspoch Ruldua, Maria Lluïsa; Franco Urquiza, Edgar Adrián; Santana Pérez, Orlando Onofre; Gamez Pérez, Jose; Sanchez Soto, Miguel Angel; Velasco Perero, Jose Ignacio; Martinez Benasat, Antonio
    Encuentro del Grupo Español de Fractura
    Presentation's date: 2011-04-08
    Presentation of work at congresses

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  • Biodegradation in compost of recycled low density polyethylene/polycaprolactone blends

     Bou Serra, Jorge; Marroyo Molina, Luis Miguel; Alla Bedahnane, Abdelilah; Olle Otero, Luis; Bacardit Dalmases, Anna; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    European Polymer Congress
    Presentation's date: 2011-06-26
    Presentation of work at congresses

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  • Compuestos de PLA/o-MMT: caracterización morfológica y mecánica

     Velázquez-Infante, Julio; Franco Urquiza, Edgar Adrian; Santana Pérez, Orlando Onofre; Martinez Benasat, Antonio; Maspoch Ruldua, Maria Lluïsa; Gamez Pérez, Jose; Carrasco, F
    Congreso Nacional de Materiales Compuestos
    Presentation's date: 2011-07-06
    Presentation of work at congresses

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  • Reactive extrusion of poly(lactic acid) with styrene-acrylic-glycidil methacrylate

     Santana Pérez, Orlando Onofre; Cailloux, Jonathan; Franco Urquiza, Edgar Adrian; Bou Serra, Jorge; Carrasco, Félix; Gámez Pérez, José; Maspoch Ruldua, Maria Lluïsa
    EUROTEC
    Presentation's date: 2011-11-14
    Presentation of work at congresses

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  • Fracture behavior of quenched poly(lactic acid)

     Gamez Pérez, Jose; Velázquez Infante, Julio César; Franco Urquiza, Edgar Adrian; Pages Figueras, Pedro; Carrasco, F; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Express polymer letters
    Date of publication: 2011-01
    Journal article

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    The effect of a quenching treatment applied on heated cast sheet extruded films of two poly(lactic acid) (PLA) commercial grades, with different optical purities, was studied. The thermal and mechanical properties of the films, as well as their fracture behavior, were assessed by differential scanning calorimetry (DSC), tensile tests, and the essential work of fracture (EWF) approach. The heating-quenching treatment causes a de-aging effect with an increase in the free volume of polymer chains evidenced by a decrease in the glass transition temperature (Tg) and a decrease in the tensile stiffness and yield stress. As a result, there is an abrupt increase in ductility, finding a dramatic change in the fracture behavior, from brittle to ductile. The use of digital image correlation (DIC) of the strain field analysis during fracture testing has allowed relating the decrease on the yield stress promoted by quenching with the crack propagation kinetics. The use of the EWF method to characterize the fracture toughness of PLA has allowed to measure this enhancement on toughness, finding that the specific essential work of fracture (we) and the plastic term (!wp) parameters increased 120% and 1200%, respectively, after the quenching process.

  • Processing of poly(lactic acid)/organomontmorillonite nanocomposites: Microstructure, thermal stability and kinetics of the thermal decomposition

     Carrasco, F; Gámez Pérez, José; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Chemical engineering journal
    Date of publication: 2011-12-15
    Journal article

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  • Sobreinyección de PP-TPV. Estudio experimental de la adhesión en la interfase

     Candal Pazos, Maria Virginia
    Defense's date: 2011-07-18
    Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya
    Theses

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  • Influence of crystallinity on the fracture toughness of poly(lactic acid)/montmorillonite nanocomposites prepared by twin-screw extrusion

     Gamez Pérez, Jose; Nascimento, L.; Bou Serra, Jorge; Franco Urquiza, Edgar Adrian; Santana Pérez, Orlando Onofre; Carrasco, F.; Maspoch Ruldua, Maria Lluïsa
    Journal of applied polymer science
    Date of publication: 2011-04-15
    Journal article

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  • Determinación de la tenacidad a la fractura por diferentes metodologías de un pla con comportamiento dúctil

     Oropeza, J; Rodríguez González, Cristina; Belzunce Varela, F. Javier; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Encuentro del Grupo Español de Fractura
    Presentation's date: 2010-03-17
    Presentation of work at congresses

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    Se ha evaluado la aplicabilidad de la técnica del Trabajo Esencial de Fractura (EWF) en geometría SENB como método alternativo al concepto y metodología de Integral J. Para ello fue empleado un Poli(Ácido Láctico) amorfo sometido a un tratamiento térmico de rejuvenecimiento para favorecer su comportamiento dúctil. Los resultados demuestran que la técnica de EWF puede ser empleada como una metodología alternativa y sencilla con la que se puede determinar el valor, en condiciones de deformación plana, de Jo según lo establecido en el protocolo ESIS 2000 y norma ASTM E813-87. Para la validación del rango de longitudes de ligamento a emplear se considera como válida la solución para geometría SENB del Slip-line field con una tolerancia de alrededor un 10% .

  • Preparación y caracterización de espumas microcelulares nanoreforzadas

     de Redondo Realinho, Vera Cristina; de Sousa Pais Antunes, Marcelo; Santana Pérez, Orlando Onofre; Sanchez Soto, Miguel Angel; Velasco Perero, Jose Ignacio
    Congreso Nacional de Materiales
    Presentation's date: 2010-06-24
    Presentation of work at congresses

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  • Essential work of fracture testing of PC-rich PET/PC blends with and without transesterification catalysts

     Al-Jabareen, Ahmad; Illescas Fernandez, Silvia; Maspoch Ruldua, Maria Lluïsa; Santana Pérez, Orlando Onofre
    Journal of materials science
    Date of publication: 2010-06
    Journal article

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  • Effect of the recycling and annealing on the mechanical and fracture properties of poly(lactic acid)

     Nascimento, L.; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Velasco Perero, Jose Ignacio; Maspoch Ruldua, Maria Lluïsa; Franco Urquiza, Edgar Adrian
    Journal of polymers and the environment
    Date of publication: 2010-12
    Journal article

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    The aim of this work is to evaluate the use of Poly(lactic acid)(PLA) industrial waste as a source of raw material for certain applications, as well to understand the effects of the annealing on the fracture behaviour of PLA. PLA waste has been simulate by an initial step of extrusion in a single screw extruder and pelletizing. Specimens of virgin and reprocessed PLA were obtained by injection molding. An anneling treatment capable of increasing the percentage of cristallinity (determined by differential scanning calorimetry) was also analyzed in reprocessed and non reprocessed specimens. The fracture behaviour was studied at slow and high testing speed, applying the linear elastic fracture mechanics (LEFM) on single edge notched bend (SENB) specimens. This study revealed that the fracture toughness of the reprocessed PLA was basically the same that the virgin PLA and also that the increase in the crystalline fraction produced an improvement on the fracture toughness, at slow loagind rate.

  • Processing of poly(lactic acid): Characterization of chemical structure, thermal stability and mechanical properties

     Carrasco Alonso, Felix Angel; Pages Figueras, Pedro; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Polymer degradation and stability
    Date of publication: 2010-02
    Journal article

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    The processing of poly(lactic acid) (injection and extrusion/injection) as well as annealing of processed materials were studied in order to analyze the variation of its chemical structure, thermal degradation and mechanical properties. Processing of PLA was responsible for a decrease in molecular weight, as determined by GPC, due to chain scission. The degree of crystallinity was evaluated by means of differential scanning calorimetry and X-ray diffraction. It was found that mechanical processing led to the quasi disappearance of crystal structure whereas it was recovered after annealing. These findings were qualitatively corroborated by means of FTIR. By analyzing 1H NMR and 13C NMR chemical shifts and peak areas, it was possible to affirm that the chemical composition of PLA did not change after processing, but the proportion of methyl groups increased, thus indicating the presence of a different molecular environment. The thermal stability of the various materials was established by calculating various characteristic temperatures from thermograms as well as conversion and conversion derivative curves. Finally, the mechanical behaviour was determined by means of tensile testing (Young modulus, yield strength and elongation at break).

  • Influence of processing on the ethylene-vinyl alcohol (EVOH) properties: Application of the successive self-nucleation and annealing (SSA) technique

     Franco Urquiza, Edgar Adrian; Santana Pérez, Orlando Onofre; Gamez Pérez, Jose; Martinez Benasat, Antonio; Maspoch Ruldua, Maria Lluïsa
    Express polymer letters
    Date of publication: 2010-03
    Journal article

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    Films of EVOH copolymers, processed three times by twin-screw extrusion were prepared using a cast-film line. The variation on the melt flow rate (MFR) and rheological behaviour of the films were determined, as well as the thermal properties assessed by differential scanning calorimetry (DSC) and dynamic-mechanical thermal analysis (DMTA). As the results showed that the reprocessing induced an increase in the viscosity and orientation of the films, it was suggested that structural modifications from chain-extension or cross-linking reactions promoted by hydroxyl and residual acetoxyl groups, could be occurring. The successive self-nucleation and annealing (SSA) technique was applied, evidencing the structural modifications on the EVOH copolymer.

  • The effect of organo-modifier on the structure and properties of poly[ethylene¿(vinyl alcohol)]/organo-modified montmorillonite composites

     Franco Urquiza, Edgar Adrian; Gamez Pérez, Jose; Sanchez Soto, Miguel Angel; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Polymer international
    Date of publication: 2010-02-02
    Journal article

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  • Fracture behaviour of de-aged poly(lactic acid) assessed by essential work of fracture and J-Integral methods

     Santana Pérez, Orlando Onofre; Rodríguez, C.; Belzunce Varela, F. Javier; Gamez Pérez, Jose; Carrasco, F.; Maspoch Ruldua, Maria Lluïsa
    Polymer testing
    Date of publication: 2010-12
    Journal article

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    The applicability of the essential work of fracture (EWF) in SENB geometry as an alternative to the J-integral methodology has been assessed. An amorphous poly(lactic acid) (PLA) with ductile behaviour promoted by a de-ageing heat treatment has been used. The results demonstrate that the EWF technique can be used as a simple alternative methodology to determine the J0.2 value in plane strain conditions, using the ESIS-2000 protocol and ASTME813-87 standard. As a validation of the range of ligament length to be used in the EWF analysis, the SENB solution of the Slip Line Field theory could be employed.

  • Kinetics of the thermal decomposition of processed poly(lactic acid)

     Carrasco, F.; Pages Figueras, Pedro; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Polymer degradation and stability
    Date of publication: 2010-12
    Journal article

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  • Processing of poly (lactic acid) (PLA) and PLA / montmotillonite nanocomposites in a pilot plant: a study of structural changes and thermal stability

     Pages Figueras, Pedro; Carrasco, F.; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Maspoch Ruldua, Maria Lluïsa
    Afinidad: revista de química teórica y aplicada
    Date of publication: 2010-03
    Journal article

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    Se aplican procesos de transformación y tratamiento de termoplásticos (inyección, extrusión-inyección y recocido) al àcido poliláctico (PLA) y a determinados nanocompuestos PLA/montmorillonita, con objeto de estudiar las variaciones de la estructura físico-química del PLA durante su procesado en planta piloto. El grado de cristalinidad de los materiales se estudió mediante calorimetría de barrido diferencial (DSC), difracción de rayos X (XRD) y espectroscopía FTIR, constatándoses que el procesado mecánico provoca la pràctica desaparición de la estructura cristalina del PLA, que se recupera mediante el recocido. Además, la técnica FTIR ha permitido el estudio de interacciones químicas entre los componentes de los nanocompuestos. Por otro lado, se ha estudiado la estabilidad térmica de muestras de PLA y de sus nanocompuestos, a partir de temperaturas de descomposición características, que se obtienen de los termogramas TGA.

  • Aplicación de la mecánica de la fractura post-cedencia a polímeros

     Maspoch Ruldua, Maria Lluïsa; Franco Urquiza, Edgar Adrian; Gamez Pérez, Jose; Sanchez Soto, Miguel Angel; Velasco Perero, Jose Ignacio; Santana Pérez, Orlando Onofre; Martinez Benasat, Antonio
    Revista latinoamericana de metalurgia y materiales
    Date of publication: 2010-07-30
    Journal article

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    La técnica del trabajo esencial de fractura (EWF) se ha utilizado en la caracterización a fractura de materiales que desarrollan una amplia ductilidad y donde ocurre una completa cedencia antes del inicio de la propagación de la grieta. De esta manera, la técnica EWF caracteriza la fractura post-cedencia determinando dos parámetros: el trabajo esencial específico de fractura (we), relacionado con la superficie donde ocurre el proceso real de fractura, y el trabajo no esencial específico de fractura (wp), relacionado con el trabajo plástico realizado en la zona exterior de la zona de fractura. La técnica EWF ha sido utilizada satisfactoriamente, especialmente en polímeros, permitiendo el estudio de la influencia de distintas variables sobre el comportamiento a fractura. Su elevada sensibilidad así como su fácil aplicabilidad le confieren amplias ventajas sobre otras técnicas tales como la integral J. En este trabajo se describen los fundamentos de la técnica EWF y se recopilan algunos ejemplos de su aplicación, presentando un breve resumen de las aportaciones más relevantes realizadas por nuestro grupo de investigación sobre la técnica del EWF.

  • Effects of composition and transesterification catalysts on the physico-chemical and dynamic properties of PC/PET blends rich in PC

     Al-Jabareen, Ahmad; Illescas Fernandez, Silvia; Maspoch Ruldua, Maria Lluïsa; Santana Pérez, Orlando Onofre
    Journal of materials science
    Date of publication: 2010-12
    Journal article

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  • The Essential Work of Fracture (EWF) method. Analyzing the Post-Yielding Fracture Mechanics of polymers

     Martinez Benasat, Antonio; Gamez Pérez, Jose; Sanchez Soto, Miguel Angel; Velasco Perero, Jose Ignacio; Maspoch Ruldua, Maria Lluïsa; Santana Pérez, Orlando Onofre
    Engineering failure analysis
    Date of publication: 2009-12
    Journal article

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  • Fracture behaviour of poly[ethylene¿(vinyl alcohol)]/organo-clay composites

     Maspoch Ruldua, Maria Lluïsa; Franco Urquiza, Edgar Adrian; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Sanchez Soto, Miguel Angel
    Polymer international
    Date of publication: 2009-04-14
    Journal article

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    BACKGROUND: Ethylene–(vinyl alcohol) (EVOH) copolymer/organo-modified montmorillonite (OMMT) composites were investigated. Composites with two different percentages by weight of OMMT were prepared using a melt-extrusion procedure in a twin-screw extruder, using EVOH asmatrix. Filmsmade of EVOH and EVOH/OMMT composites were prepared in a cast-film extrusion line. RESULTS: The mechanical properties were evaluated by tensile tests and the fracture behaviour was analysed using the essential-work-of-fracture (EWF) method. Fracture characterization was carried out for the two main processing directions: melt flow direction and transverse direction. Fractographic observations were made using scanning electron microscopy. CONCLUSION: The tensile test results indicated good compatibility between EVOH and OMMT. In addition, the fracture tests showed the influence of the clay particle arrangement on the fracture behaviour, showing an increase in the specific essential work of fracture, we, which was attributed to the EVOH–OMMT interaction. The plastic term, βwp, showed different trends depending on the test direction, explained by the size of the plastic zone and the restrictions to the EVOH plastic flow promoted by the clay particles. In this sense, the EWF method is shown to be a very useful tool for the analysis of structure–property relationships in polymer–organo-clay composites.

  • Modificación de PC mediante extrusión reactiva: comportamiento a fractura

     Santana Pérez, Orlando Onofre; Al-Jabareen, Ahmad; Illescas Fernandez, Silvia; Abt, Tobias Martin; Sanchez Soto, Miguel Angel
    Reunión del Grupo Especializado de Polímeros
    Presentation's date: 2009-09-20
    Presentation of work at congresses

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  • Influencia de los parámetros estructurales en el comportamiento a fractura de copolímeros en bloque de etileno-propileno

     Salazar López, Alicia; Rodríguez Pérez, Jesús; Santana Pérez, Orlando Onofre; Martinez Benasat, Antonio
    Anales de mecánica de la fractura
    Date of publication: 2009-03-25
    Journal article

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  • Poly(Ethylene Terephthalate)/Polycarbonate Blends Prepared by Reactive Extrusion: Thermal and Mechanical Characterizations

     Aljabareen, Ahmad I A
    Defense's date: 2009-01-27
    Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya
    Theses

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  • Preparación y caracterización de nanocompuestos Evoh/Montmorillonita

     Franco Urquiza, Edgar Adrian
    Defense's date: 2009-12-04
    Department of Materials Science and Metallurgy, Universitat Politècnica de Catalunya
    Theses

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  • Trabajo esencial de fractura de láminas de policarbonato modificado mediante extrusión reactiva con PET

     Al-Jabareen, Ahmad; Illescas Fernandez, Silvia; Sanchez Soto, Miguel Angel; Santana Pérez, Orlando Onofre
    Anales de mecánica de la fractura
    Date of publication: 2008-03
    Journal article

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  • Influencia de un tratamiento termico sobre el comportamiento a fractura del poli(ácido Láctico)

     Maspoch Ruldua, Maria Lluïsa; Nascimento, L; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre
    Anales de mecánica de la fractura
    Date of publication: 2008-03
    Journal article

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  • Aplicación de la técnica de autonucleación-recocido sucesivos (SSA) en un copolímero evoh: efecto del procesamiento

     Santana Pérez, Orlando Onofre; Al-Jabareen, Ahmad; Maspoch Ruldua, Maria Lluïsa; Franco Urquiza, Edgar Adrian
    Congreso Nacional de Materiales
    Presentation's date: 2008-06-18
    Presentation of work at congresses

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  • Desarrollo de una herramienta multimedia interactiva para el estudio del comportamiento mecánico de materiales plásticos

     Maspoch Ruldua, Maria Lluïsa; Santana Pérez, Orlando Onofre
    Taller Iberoamericano de Educación en Ciencia e Ingenieria de Materiales
    Presentation's date: 2008-12-02
    Presentation of work at congresses

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  • Desarrollo de una herramienta para el aprendizaje del comportamento mecanico de polimeros

     Maspoch Ruldua, Maria Lluïsa; Santana Pérez, Orlando Onofre
    Taller Iberoamericano de Educación en Ciencia e Ingeniería de Materiales
    Presentation's date: 2008-12-02
    Presentation of work at congresses

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  • Aplicación de la técnica de autonucleación-recocido sucesivos (SSA) en un copolímero EVOH: Efecto del procesamiento

     Santana Pérez, Orlando Onofre
    Congreso Nacional de Materiales
    Presentation's date: 2008-06-19
    Presentation of work at congresses

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  • Efecto del medio tensoactivo sobre las propiedades mecánicas del Poliestireno cristal

     Santana Pérez, Orlando Onofre
    Simposio Latinoamericano y Congreso Iberoamericano de Polímeros
    Presentation's date: 2008-07-15
    Presentation of work at congresses

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  • PC MODIFICATION BY REACTIVE BLENDING EXTRUSION WITH PET: FRACTURE ANALYSIS USING EWF APPROACH

     Santana Pérez, Orlando Onofre
    5th International conference on fracture of polymers, composites and adhesives - 5th TC4 conference
    Presentation's date: 2008-09-07
    Presentation of work at congresses

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  • Trabajo esencial de fractura de láminas de policarbonato modificado mediante extrusión reactiva

     Al-Jabareen, A; Illescas Fernandez, Silvia; Sanchez Soto, Miguel Angel; Santana Pérez, Orlando Onofre
    Encuentro del Grupo Español de Fractura
    Presentation's date: 2008-03-07
    Presentation of work at congresses

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  • Effect of injection conditions on fracture behaviour of HIPS at low strain rate studied by design of experiments

     Santana Pérez, Orlando Onofre
    66th Annual Technical Conference of the Society of Plastics Engineers
    Presentation's date: 2008-05-04
    Presentation of work at congresses

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  • Influencia de un tratamiento térmico sobre el compostamiento a fractura del poli(ácido láctico)

     Maspoch Ruldua, Maria Lluïsa; Gamez Pérez, Jose; Santana Pérez, Orlando Onofre
    Encuentro del Grupo Español de Fractura
    Presentation of work at congresses

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  • Aplicación de la técnica de autonucleación-recocido sucesivos (SSA) en un copolímero EVOH: Efecto del procesamiento

     Santana Pérez, Orlando Onofre
    Congreso Nacional de Materiales
    Presentation's date: 2008-06-19
    Presentation of work at congresses

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  • Effect of injection conditions on fracture behaviour of HIPS at low strain rate studied by design of experiments

     Sánchez, J J; Santana Pérez, Orlando Onofre; Gordillo Aubert, Antonio
    66th Annual Technical Conference of the Society of Plastics Engineers
    Presentation of work at congresses

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  • Influence of the temperature on the fracture behaviour of Ehtylene-Propylene block copolymer

     Santana Pérez, Orlando Onofre
    5th International conference on fracture of polymers, composites and adhesives - 5th TC4 conference
    Presentation's date: 2008-09-07
    Presentation of work at congresses

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  • Use of extensometers on essential work of fracture (EWF) tests

     Gamez Pérez, Jose; Santana Pérez, Orlando Onofre; Martinez Benasat, Antonio; Maspoch Ruldua, Maria Lluïsa
    Polymer testing
    Date of publication: 2008-06
    Journal article

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