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  • A new epoxy based layered silicate nanocomposite using a hyperbranched polymer: study of the curing reaction and nanostructure development

     Cortes Izquierdo, M. Pilar; Fraga Rivas, Iria; Calventus Sole, Yolanda; Hutchinson, John M.
    International Conference on Modification, Degradation and Stabilization of Polymers
    Presentation's date: 2013-09-09
    Presentation of work at congresses

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    Polymer layered silicate (PLS) nanocomposites based on epoxy resins have been widely studied previously [1], but the anticipated dramatic enhancement of their properties has not yet been realised. One approach to overcoming this problem that has recently been investigated is to incorporate hyperbranched polymers into these systems [2]. The supposed advantages of this approach are both to improve the dispersion of the clay in the epoxy resin matrix and also to increase the degree of exfoliation that takes place when the system is cured. In the present work, we further investigate this idea by fabricating PLS nanocomposites based upon a bifunctional epoxy resin and an ¿NH terminated poly(ethyleneimine) hyperbranched polymer, which acts as the curing agent. The effect of the clay content is studied and the results are compared also with previous work in which the curing agent was a diamine [3].

  • Influence of the isothermal cure temperature on the nanostructure and thermal properties of an epoxy layered silicate nanocomposite

     Shiravand, Fatemeh; Hutchinson, John M.; Calventus Sole, Yolanda
    Polymer engineering and science
    Date of publication: 2013-03-08
    Journal article

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    The cure kinetics of triglycidyl p-amino phenol (TGAP) epoxy resin with a diamine (4,4-diamino diphenyl sulphone [DDS]), reinforced with montmorillonite (MMT), has been studied by differential scanning calorimetry. The isothermal cure reaction consists of two parts: a rapid intra-gallery reaction, attributed to homopolymerization of the TGAP catalyzed by the MMT and the extra-gallery cross-linking reaction of the TGAP with the DDS. Increasing cure temperature promotes the intra-gallery reaction, which should promote an exfoliated nanostructure; this is confirmed by transmission electron microscopy. These results indicate that this system (TGAP/DDS/MMT) is an excellent candidate for achieving exfoliated polymer-layered silicate nanocomposites and identifies a protocol for optimizing the degree of exfoliation. POLYM. ENG. SCI., 2013. © 2013 Society of Plastics Engineers

    The cure kinetics of triglycidyl p-amino phenol (TGAP) epoxy resin with a diamine (4,4-diamino diphenyl sulphone [DDS]), reinforced with montmorillonite (MMT), has been studied by differential scanning calorimetry. The isothermal cure reaction consists of two parts: a rapid intra-gallery reaction, attributed to homopolymerization of the TGAP catalyzed by the MMT and the extra-gallery cross-linking reaction of the TGAP with the DDS. Increasing cure temperature promotes the intra-gallery reaction, which should promote an exfoliated nanostructure; this is confirmed by transmission electron microscopy. These results indicate that this system (TGAP/DDS/MMT) is an excellent candidate for achieving exfoliated polymer-layered silicate nanocomposites and identifies a protocol for optimizing the degree of exfoliation.

  • Isothermal curing of polymer layered silicate nanocomposites based upon epoxy resin by means of anionic homopolymerisation

     Roman Concha, Frida Rosario; Calventus Sole, Yolanda; Colomer Vilanova, Pere; Hutchinson, John M.
    Thermochimica acta
    Date of publication: 2013-12-20
    Journal article

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    The use of an initiator, 4-(dimethylamino) pyridine (DMAP), to promote an anionic homopolymerisation reaction for the isothermal cure of polymer layered silicate (PLS) nanocomposites based on an epoxy resin, as well as the effect of the nanoclay content, have been studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dielectric relaxation spectroscopy (DRS) and transmission electron microscopy (TEM). The vitrification phenomenon was observed during the isothermal cure process, and it was found that the nanocomposite with a low clay content (2 wt%), denoted EDM2, shows improved thermal properties with respect to the unreinforced resin (denoted ED), while the nanocomposite with a higher clay content (5 wt%), denoted EDM5, displayed inferior properties. The cure kinetics were analysed by different methods, and it was observed that the activation energy and kinetic parameters of EDM2 were lower compared to the other two systems. Examination of the nanostructure of the cured EDM2 nanocomposite showed partial exfoliation, while the EDM5 system retains an intercalated nanostructure. In the DRS studies of the curing process of the EDM2 system, two dielectric relaxations were detected, which are associated with the molecular mobility in the curing reaction which takes place both outside and inside the clay galleries.

  • Elastomeric epoxy nanocomposites: Nanostructure and properties

     Lipinska, Magdalena; Hutchinson, John M.
    Composites science and technology
    Date of publication: 2012-03-08
    Journal article

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    In polymer layered silicate nanocomposites, significant differences have been reported between the effects of the nano-reinforcement on rigid and elastomeric nanocomposites. In this paper, we have studied elastomeric nanocomposites based upon DGEBA epoxy resin filled with montmorillonite (MMT) and cured with a long-chain polyoxypropylene diamine, for comparison with analogous rigid nanocomposites. Ultrasonic mixing was used to disperse the MMT in the matrix to improve homogeneity and decrease the agglomerate size. Two different methods of nanocomposite preparation were used in which the MMT was first swollen with either the curing agent or the epoxy before the addition of, respectively, DGEBA or diamine. A better dispersion of the nanoclay in the matrix and a greater amount of intercalation occurred when the MMT was first swollen with the diamine. The effect of MMT concentrations up to 8 wt.% on the mechanical behaviour of the epoxy/MMT nanocomposites was investigated. It was found that the addition of MMT increased the tensile strength and modulus, although SAXS and TEM indicated that a significant fraction of the clay layers were not exfoliated. Nevertheless, the addition of the clay resulted in changes in the fracture surfaces, as indicated by SEM, consistent with the tensile results and indicative of toughening.

  • Intra- and extra-gallery reactions in tri-functional epoxy polymer layered silicate nanocomposites

     Hutchinson, John M.; Shiravand, Fatemeh; Calventus Sole, Yolanda
    Journal of applied polymer science
    Date of publication: 2012-09-05
    Journal article

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    Achieving a high degree of exfoliation in epoxy-based polymer layered silicate (PLS) nanocomposites is crucial to their successful industrial application, but has hitherto proved elusive. In this work, a system is presented which shows significant promise in this respect. The isothermal cure of PLS nanocomposites based upon a tri-functional epoxy resin (TGAP) has been studied by DSC, and displays two exothermic peaks. The first peak, very rapid, relates to a homopolymerization reaction within the intra-gallery regions, while the second peak reflects the bulk crosslinking reaction. The occurrence of the intra-gallery reaction before the bulk reaction enhances the degree of exfoliation in the cured nanocomposite. Furthermore, pre-conditioning the resin/clay mixture before adding the curing agent and effecting the isothermal cure also allows a greater extent of intra-gallery reaction to occur before the extra-gallery epoxy-amine reaction. Consequently, this system results in a high degree of exfoliation, as revealed by transmission electron microscopy.

  • NUEVOS TERMOESTABLES MEJORADOS BASADOS EN RESINAS EPOXI Y POLIMEROS DENDRITICO

     Cortes Izquierdo, M. Pilar; Fraga Rivas, Iria; Roman Concha, Frida Rosario; Colomer Vilanova, Pere; Calventus Sole, Yolanda; Hutchinson, John M.
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    Identification of nanostructural development in epoxy polymer layered silicate nanocomposites from the interpretation of differential scanning calorimetry and dielectric spectroscopy  Open access

     Roman Concha, Frida Rosario; Calventus Sole, Yolanda; Colomer Vilanova, Pere; Hutchinson, John M.
    Thermochimica acta
    Date of publication: 2012-05-08
    Journal article

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    The effect of nanoclay on the non-isothermal cure kinetics of polymer layered silicate nanocomposites based upon epoxy resin is studied by calorimetric techniques (DSC and TGA) and by dielectric relaxation spectroscopy (DRS) in non-isothermal cure at constant heating rate. The cure process takes place by homopolymerisation, initiated anionically using 3 wt% dimethylaminopyridine (DMAP), and the influence of the nanoclay content has been analysed. Interesting differences are observed between the nanocomposites with 2 wt% and 5 wt% clay content. At low heating rates, these samples vitrify and then devitrify during the cure. For the sample with 2 wt% clay, the devitrification is accompanied by a thermally initiated homopolymerisation, which can be identified by DRS but not by DSC. The effect of this is to improve the exfoliation of the nanocomposite with 2 wt% clay, as verified by transmission electron microscopy, with a corresponding increase in the glass transition temperature. These observations are interpreted in respect of the nanocomposite preparation method and the cure kinetics.

  • Isothermal and non-isothermal cure of a tri-functional epoxy resin (TGAP): a stochastic TMDSC study

     Hutchinson, John M.; Calventus Sole, Yolanda; Shiravand, Fatemeh; Fraga Rivas, Iria
    Thermochimica acta
    Date of publication: 2012-02-10
    Journal article

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    The isothermal cure of a highly reactive tri-functional epoxy resin, tri-glycidyl para-amino phenol (TGAP), with diamino diphenyl sulphone (DDS), at two different cure temperatures Tc has been studied by both conventional differential scanning calorimetry (DSC) and by a stochastic temperature modulated DSC technique, TOPEM. From a series of isothermal cure experiments for increasing cure times, the glass transition temperature Tg as a function of isothermal cure time is determined by conventional DSC from a second (non-isothermal) scan, and the vitrification time tv is obtained as the time at which Tg = Tc. In parallel, TOPEM experiments at the same Tc lead directly to the determination of tv from the sigmoidal change in the quasi-static heat capacity. It is not possible to identify the glass transition temperature of the fully cured system, Tg∞, in a third scan by conventional DSC. In contrast, with TOPEM a second (non-isothermal) scan at 2 K/min after the isothermal cure gives rise to three separate transitions: devitrification of the partially cured and vitrified material; almost immediate vitrification as the Tg of the system again rises; finally another devitrification, at a temperature approximating closely to Tg∞. Thus with TOPEM it is possible to obtain a calorimetric measure of the glass transition temperature of this fully cured system.

  • The Use of Matlab in the study of the glass transition and vitrification in polymers

     Hutchinson, John M.; Fraga Rivas, Iria
    Date of publication: 2011-09-01
    Book chapter

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  • Vitrification and devitrification during the non-isothermal cure of a thermoset. A TOPEM Study

     Fraga Rivas, Iria; Hutchinson, John M.; Montserrat Ribas, Salvador
    Journal of thermal analysis and calorimetry
    Date of publication: 2010-03
    Journal article

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    The processes of vitrification and devitrification that occur in an epoxy resin when it cures nonisothermally with a hardener are studied in terms of their frequency dependence and as a function of the heating rate. A novel modulated DSC technique, TOPEM, has been used which permits the evaluation of the frequency dependence for a single sample in a scan at constant underlying heating rate, thus avoiding errors arising from the composition of the sample. The effects of both frequency and heating rate on vitrification and devitrification are investigated. Some advantages of this technique are observed and discussed.

  • Vitrification and devitrification during the non-isothermal cure of a thermoset. Theoretical model and comparison with calorimetric experiments

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Macromolecular chemistry and physics
    Date of publication: 2010-01-05
    Journal article

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  • Study of thermal transitions in polymers by a multifrequency modulated DSC technique  Open access  awarded activity

     Fraga Rivas, Iria
    Defense's date: 2010-02-26
    Department of Physics and Nuclear Engineering, Universitat Politècnica de Catalunya
    Theses

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    Differential Scanning Calorimetry (DSC) is one of the most widely used thermal analysis techniques for the study of transitions and relaxation processes in polymers and also in other materials. It measures the heat flow as a function of time and/or temperature, and determines the energy released or absorbed by a sample when it is heated (cooled) or maintained at a constant temperature. Its advantages are that it is fast and sensitive, the amount of sample needed is small (~mg), it could be in the liquid or solid state and the sample preparation is easier than for some other techniques. Nevertheless, it present some drawbacks, such as not being able to separate different overlapping transitions that happen in the same temperature range, the difficulty of detecting very weak transitions, or the requirement for multiple experiments to determine heat capacities that increases the experimental time needed. Temperature modulated DSC techniques (TMDSC) were introduced in the market more than 16 years ago. In these techniques a periodic temperature modulation of small amplitude is superimposed on the underlying rate of conventional DSC. This superposition gives two different heating rates: the underlying and the instantaneous due to the sinusoidal signal, thus permitting a better resolution and sensitivity (in DSC a better resolution gives a worse sensitivity and vice versa) and the evaluation of the heat capacity in real time. TMDSC is able to determine not only the total heat flow but also its two individual components usually referred to as “reversing” and “non-reversing”, thus it is possible to separate overlapped transitions. Although TMDSC offers more information than that available by DSC it also shows some drawbacks as the use of lower underlying heating rates than in conventional DSC which leads to longer experiments, or the requirement of making a separate scan for each frequency if one wishes to study, for example, the frequency dependence of a certain phenomenon. More recently, in 2005, TOPEM, a new technique of TMDSC from Mettler-Toledo, was commercialised. Instead of being based upon a periodic modulation of the heating rate, as is the situation with other TMDSC techniques, TOPEM uses a stochastic modulation of the heating or cooling rate by means of random pulses of temperature. This stochastic perturbation introduces a broad frequency spectrum in the response, which implies that TOPEM is apparently able to determine the complex heat capacity over a range of frequencies in a single scan. In the present thesis, a detailed description of the bases and operation of TOPEM is presented, showing the differences between the other calorimetric techniques, DSC and TMDSC. All the parameters which define an experiment and the parameters needed to make an evaluation of the experimental response are explained. The glass transition of polycarbonate is selected to make an initial study of the influence of all the different parameters (experimental and calculation) on the results of an experiment. Different samples are employed and different experiments by TOPEM and ADSC (TMDSC technique specific of Mettler- Toledo) are performed and compared. The limits and advantages offered by TOPEM are observed and presented here, and with a more profound understanding of the technique as a result, additional materials and transitions are studied. In the next part, an epoxy resin with a diamine is selected to be studied. The vitrification during the isothermal cure is studied by TOPEM. The results are again compared with those obtained by TMDSC and the additional information obtained is analyzed and compared with additional results obtained from the literature. With the aim to confirm some experimental data observed, a simulation is made with MATLAB to confirm the experimental results. It is found that the theoretical results not only predict the calorimetric data, but also those obtained from dielectric analysis at higher frequencies which were extracted from the literature. In the next part, the same epoxy resin with a diamine is selected. The vitrification and devitrification during the non-isothermal cure is analyzed by TOPEM. The results obtained permit to construct a CHT diagram (conversion-time-temperature) which characterized the system. As in the previous case a simulation is made with MATLAB and the theoretical results obtained compare well with the experimental data. Finally, some preliminary experiments related to other transitions are presented and are planned to be studied in the future.

    La calorimetría diferencial de barrido (DSC) es una técnica ampliamente utilizada desde el año 1963 en la caracterización térmica de polímeros y otros materiales. En DSC se mide el calor absorbido o emitido por una muestra cuando es sometida a un programa de calentamiento (enfriamiento) o bien es mantenida a una temperatura constante. Sus ventajas es que es una técnica rápida, con gran sensibilidad, no requiere una preparación previa de las muestras, el tamaño de las mismas es pequeño (~mg) y pueden analizarse en estado líquido o sólido. Sin embargo, presenta algunas desventajas: no es posible detectar transiciones muy débiles, ni separar aquellas que aparecen superpuestas en el mismo rango de temperaturas y para la determinación de capacidades caloríficas exige la realización de varios experimentos separados lo que se traduce en un tiempo de experimentación en ocasiones muy largo. Hace 15 años comenzó a comercializarse la calorimetría diferencial de barrido con temperatura modulada (TMDSC). Lo que la diferencia de la calorimetría DSC convencional es que al tipo de barrido utilizado en DSC se superpone una señal periódica sinusoidal de modulación de temperatura de pequeña amplitud. Esta superposición da lugar a dos tipos de velocidad: una es la velocidad base de calentamiento (enfriamiento) y la otra de superposición de la señal modulada, algo que proporciona ciertas ventajas. Por ejemplo ofrece al mismo tiempo una buena resolución y una buena sensibilidad (en DSC la mejora de la sensibilidad lleva asociada pérdida de resolución y viceversa) o la evaluación de la capacidad calorífica a tiempo real. La TMDSC permite separar el flujo de calor total en dos componentes, reversing y non-reversing, permitiendo así separar transiciones que aparezcan superpuestas. Aunque si bien la TMDSC ofrece más información que el DSC convencional también presenta algunas desventajas como son el uso de velocidades más lentas que en DSC lo que implica tiempos de experimentación largos, o la necesidad de hacer un barrido para cada frecuencia en el caso de querer estudiar la dependencia en frecuencias de un determinado fenómeno. En el año 2005, se comenzó a comercializar TOPEM, una técnica también de temperatura modulada de Mettler-Toledo, en la que la modulación de la temperatura en lugar de ser periódica es estocástica, lo que introduce un amplio espectro de frecuencias en la respuesta cuya principal ventaja es que permite analizar la capacidad calorífica de una muestra en un rango de frecuencias realizando sólo un único barrido. En la presente tesis se ofrece una descripción de las bases del funcionamiento de TOPEM, mostrando las diferencias que presenta respecto a las mencionadas técnicas calorimétricas DSC y TMDSC. Se da una explicación detallada de todos parámetros que definen un experimento, así como los necesarios para realizar el cálculo de la respuesta experimental obtenida y otros parámetros importantes a tener en cuenta al utilizar TOPEM. En un primer estudio se selecciona la transición vítrea del policarbonato para comenzar a trabajar con la nueva técnica. Con diferentes muestras y realizando experimentos tanto de TOPEM como de ADSC (nombre de la técnica TMDSC específica de la casa comercial Mettler-Toledo) se comparan los resultados obtenidos con ambas técnicas. Se realiza un minucioso análisis de la influencia de los parámetros experimentales y de evaluación en los resultados obtenidos. Se observan y presentan los límites y ventajas ofrecidos por TOPEM y se establece una metodología de experimentación y evaluación con el fin de trabajar con otros materiales y transiciones. En la siguiente parte, se selecciona una resina epoxi con una diamina, y se aplica la técnica a la vitrificación durante el curado isotermo. Los resultados se comparan con los obtenidos por TMDSC y la información adicional obtenida es analizada y comparada con resultados extraídos de la bibliografía. Con el fin de confirmar algunos datos, se realizó una simulación con MATLAB que además de coincidir con los resultados experimentales previos, también coincide con diferentes resultados obtenidos con análisis dieléctrico a más altas frecuencias. En la siguiente parte, la misma resina epoxi con la diamina es sometida a curados no –isotermos para estudiar su vitrificación y posterior devitrificación. Se comprobaron las ventajas ofrecidas por TOPEM y se construyó un diagrama CHT (conversión-tiempo-temperatura) para caracterizar el sistema. Como en el caso anterior, una simulación realizada con MATLAB predice los resultados obtenidos experimentalmente. Por último, se presentan algunos experimentos previos realizados con diversos materiales en los que se obtienen interesantes resultados para ser ampliados y analizados en el futuro.

  • Terephthalate copolyesters and nanocomposites produced by ring opening polymerization

     González Vidal, Nathalie
    Defense's date: 2010-06-04
    Department of Chemical Engineering, Universitat Politècnica de Catalunya
    Theses

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  • Thermal and oxidative degradation of epoxy based layered silicate nanocomposites

     Roman Concha, Frida Rosario; Calventus Sole, Yolanda; Hutchinson, John M.; Montserrat Ribas, Salvador
    Congreso Nacional de Materiales Compuestos
    Presentation's date: 2009-10-07
    Presentation of work at congresses

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    The thermal oxidative degradation of several polymer/clay nanocomposites with a range of clay contents has been determined. It is found that the dispersion of the clay in the resin matrix plays a crucial role in the degradation process, and hence emphasises the importance of this aspect of nanocomposite preparation.

  • Vitrification and devitrification during the non-isothermal cure of a thermoset studied by TOPEM

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Thermal Analysis UserCom
    Date of publication: 2009
    Journal article

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  • Determination of the glass transition temperature: methods correlation and structural heterogeneity

     Hutchinson, John M.
    Journal of thermal analysis and calorimetry
    Date of publication: 2009-12
    Journal article

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    The definition of the glass transition temperature, Tg, is recalled and its experimental determination by various techniques is reviewed. The diversity of values of Tg obtained by the different methods is discussed, with particular attention being paid to Differential Scanning Calorimetry (DSC) and to dynamic techniques such as Dynamic Mechanical Thermal Analysis (DMTA) and Temperature Modulated DSC (TMDSC). This last technique, TMDSC, in particular, is considered in respect of ways in which the heterogeneity of the glass transformation process can be quantified.

  • Vitrification during the isothermal cure of a thermoset studied by TOPEM

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Thermal Analysis UserCom
    Date of publication: 2009
    Journal article

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  • NUEVOS TERMOESTABLES HIBRIDOS NANOESTRUCTURADOS CON PROPIEDADES MEJORADAS A BASE DE RESINS EPOXI Y POLIMEROS HIPERRMIFICADOS

     Calventus Sole, Yolanda; Montserrat Ribas, Salvador; Cortes Izquierdo, M. Pilar; Fraga Rivas, Iria; Hutchinson, John M.; Roman Concha, Frida Rosario; Colomer Vilanova, Pere
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  • POLÍMERS TERMOESTABLES EPOXIDICS

     Salla Tarrago, Jose M.; Cadenato Matia, Ana Maria; Morancho Llena, Jose Maria; Calventus Sole, Yolanda; Hutchinson, John M.; Fernandez Francos, Xavier; Roman Concha, Frida Rosario; Colomer Vilanova, Pere; Fraga Rivas, Iria; Ramis Juan, Xavier
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  • Homopolymerization Effects in Polymer Layered Silicate Nanocomposites Based Upon Epoxy Resin: Implications for Exfoliation

     Pustkova, P; Hutchinson, John M.; Roman Concha, Frida Rosario; Montserrat, S
    Journal of applied polymer science
    Date of publication: 2009-10
    Journal article

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    Vitrification during the Isothermal Cure of Thermosets: Comparison of Theoretical Simulations with Temperature-Modulated DSC and Dielectric Analysis  Open access

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Macromolecular chemistry and physics
    Date of publication: 2008-10
    Journal article

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    Vitrification during the isothermal cure of a thermoset, which is monitored by dynamic techniques such as temperature-modulated differential scanning calorimetry (TMDSC) or dielectric analysis (DEA), is analyzed in terms of its dependence on frequency. A simulation was used to obtain the vitrification time as a function of frequency, considering it as the time when the (frequency-dependent) glass transition temperature, Tg, of the curing system reaches the cure temperature. Simulations were carried out at different cure temperatures. Other parameters, such as the exponents (reaction orders) in the Kamal equation, l in the DiBenedetto equation (controlling the dependence of Tg on the degree of cure), and the activation energy for the frequency dependence of Tg, were also considered. The results are compared with those obtained experimentally by a TMDSC technique at low frequencies and by DEA at high frequencies. From the simulations it is found that the vitrification time decreases nonlinearly with log(frequency) in the low frequency range but approaches a linear dependence at high frequencies, in agreement with experimental data.

  • Nanostructure development and cure kinetics in epoxy-based PLS nanocomposites

     Hutchinson, John M.; Montserrat Ribas, Salvador; Roman Concha, Frida Rosario
    Journal of nanostructured polymers and nanocomposites
    Date of publication: 2008-09
    Journal article

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  • Vitrification during the isothermal cure of thermosets : Part I. An investigation using TOPEM, a new temperature modulated technique

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Journal of thermal analysis and calorimetry
    Date of publication: 2008-06
    Journal article

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  • Analysis of the cure of epoxy based layered silicate nanocomposites: Reaction kinetics and nanostructure development

     Montserrat Ribas, Salvador; Roman Concha, Frida Rosario; Hutchinson, John M.; Campos Lopez, Josefa de Lourdes
    Journal of applied polymer science
    Date of publication: 2008-04
    Journal article

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  • Referee's report: Andreozzi et al

     Hutchinson, John M.
    Date: 2008-02
    Report

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  • Referee report; EUROPOL-D-08-00765

     Hutchinson, John M.
    Date: 2008-05
    Report

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  • Referee report; EUROPOL-D-08-00765R1

     Hutchinson, John M.
    Date: 2008-06
    Report

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  • Referee report; EUROPOL-D-08-00356

     Hutchinson, John M.
    Date: 2008-03
    Report

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  • Referee report; EUROPOL-D-08-00356R1

     Hutchinson, John M.
    Date: 2008-05
    Report

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  • The effect of pre-conditioning on the nanostructure and properties of polymer layered silicate

     Hutchinson, John M.
    4th International Symposium on Nanostructured and Functional Polymer-Based Materials and Nanocomposites
    Presentation's date: 2008-04-17
    Presentation of work at congresses

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  • New advances in thermal analysis: application of TOPEM to polymers

     Hutchinson, John M.
    Jornadas Internacionales: Nuevos Materiales para Pilas de Combustible
    Presentation's date: 2008-01-24
    Presentation of work at congresses

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  • Elastomeric epoxy-based silicate nanocomposites: nanostructure and properties

     Hutchinson, John M.
    Workshop on "Nanofun Poly Internal Research Projects"
    Presentation's date: 2008-02-04
    Presentation of work at congresses

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  • Unified approach to ion transport and structural relaxation in amorphous polymers and glasses

     Ingram, M D; Imrie, C T; Ledru, J; Hutchinson, John M.
    Journal of physical chemistry B
    Date of publication: 2008-01
    Journal article

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  • TOPEM, a new temperature modulated DSC technique - Application to the glass transition of polymers

     Fraga Rivas, Iria; Montserrat Ribas, Salvador; Hutchinson, John M.
    Journal of thermal analysis and calorimetry
    Date of publication: 2007-01-30
    Journal article

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    TOPEM is a new temperature modulated DSC technique, introduced by Mettler-Toledo in late 2005, in which stochastic temperature modulations are superimposed on the underlying rate of a conventional DSC scan. These modulations consist of temperature pulses, of fixed magnitude and alternating sign, with random durations within limits specified by the user. The resulting heat flow signal is analysed by a parameter estimation method which yields a so-called ‘quasi-static’ specific heat capacity and a ‘dynamic’ specific heat capacity over a range of frequencies. In a single scan it is thus possible to distinguish frequency-dependent phenomena from frequency-independent phenomena. Its application to the glass transition is examined here.

  • On the effect of montmorillonite in the curing reaction of epoxy nanocomposites

     Roman Concha, Frida Rosario; Montserrat Ribas, Salvador; Hutchinson, John M.
    Journal of thermal analysis and calorimetry
    Date of publication: 2007-01
    Journal article

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  • Estudio de la Vitrificación en el Curado Isotérmico de un Sistema Epoxi-Amina mediante "TOPEM", una Nueva Técnica Calorimétrica de Temperatura Modulada

     Hutchinson, John M.
    Reunión del grupo especializado de polímeros (RSEQ y RSEF)
    Presentation's date: 2007-09-17
    Presentation of work at congresses

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  • Aplicaciones del TOPEM en Materiales Poliméricos y Comparación con ADSC

     Hutchinson, John M.
    Jornada informativa: Seminario DSC con Temperatura Modulado y TOPEM
    Presentation's date: 2007-04-26
    Presentation of work at congresses

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  • Nanocompuestos de Epoxi con Silicato Laminar: Reticulación y Nanoestructura

     Hutchinson, John M.
    Reunión del grupo especializado de polímeros (RSEQ y RSEF)
    Presentation's date: 2007-09-17
    Presentation of work at congresses

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  • The Effect of Pre-Conditioning on the Nanostructure and Properties of Polymer Layered Silicate Nanocomposites based upon Epoxy Resin

     Hutchinson, John M.
    Reunión del grupo especializado de polímeros (RSEQ y RSEF)
    Presentation's date: 2007-09-17
    Presentation of work at congresses

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  • A Quantitative Study of the Dispersion of Montmorillonite in Epoxy Resin Following Various Mixing Procedures

     Hutchinson, John M.; Lipinska, M; Montserrat Ribas, Salvador; Roman Concha, Frida Rosario; Pages Figueras, Pedro; Lacorte Avila, M. Teresa
    3rd International Symposium on Nanostructured and Functional Polymer-Based Materials and Nanocomposites
    Presentation of work at congresses

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  • TOPEM. Vitrification during the isothermal curing of thermosets

     Fraga Rivas, Iria; Hutchinson, John M.; Montserrat Ribas, Salvador
    Date: 2007-07
    Report

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  • JTAC; Referee's report 8577

     Hutchinson, John M.
    Date: 2007-07
    Report

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  • Referee report; EUROPOL-D-07-01352

     Hutchinson, John M.
    Date: 2007-10
    Report

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  • Referee report; EUROPOL-D-07-01647

     Hutchinson, John M.
    Date: 2007-11
    Report

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  • Nanostructure Development and Cure Kinetics in Epoxy-Based PLS Nanocomposites

     Hutchinson, John M.
    3rd International Symposium on Nanostructured and Functional Polymer-Based Materials and Nanocomposites
    Presentation's date: 2007-05-13
    Presentation of work at congresses

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  • Elastomeric Layered Silicate Nanocomposites based upon DGEBA Epoxy Resin

     Hutchinson, John M.
    Reunión del grupo especializado de polímeros (RSEQ y RSEF)
    Presentation's date: 2007-09-17
    Presentation of work at congresses

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  • Nanostructure Development and Cure Kinetics in Epoxy-Based PLS Nanocomposites

     Hutchinson, John M.; Montserrat Ribas, Salvador; Roman Concha, Frida Rosario
    3rd International Symposium on Nanostructured and Functional Polymer-Based Materials and Nanocomposites
    Presentation of work at congresses

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  • The Analysis of MMT Dispersion and FTIR Study of Cure for Trifunctional Epoxy Layered Silicate Nanocomposites

     Pages Figueras, Pedro; Lacorte Avila, M. Teresa; Hutchinson, John M.; Lipinska, Magdalena; Carrasco, F; Montserrat Ribas, Salvador; Roman Concha, Frida Rosario
    Forth Meeting of the European School of Materials Science and Engineering
    Presentation of work at congresses

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