References of "Thermochimica Acta"
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See detailTemperature modulated optical refractometry: A quasi-isothermal method to determine the dynamic volume expansion coefficient
Müller, Ulrich UL; Philipp, Martine UL; Thomassey, Matthieu UL et al

in Thermochimica Acta (2013), 555

The volume expansion coefficient is a thermodynamic key parameter yielding insight into molecular cohesion and organization of condensed matter. We present here the novel experimental technique ... [more ▼]

The volume expansion coefficient is a thermodynamic key parameter yielding insight into molecular cohesion and organization of condensed matter. We present here the novel experimental technique temperature modulated optical refractometry (TMOR) to determine not only the static but also the dynamic volume expansion coefficient of transparent condensed matter of cubic or isotropic symmetry. A specialty of TMOR is its capability to measure the volume expansion coefficient under quasi-isothermal conditions. In this experimental mode TMOR is able to differentiate between static, dynamic and kinetic contributions to the volume expansion coefficient. Due to these features TMOR especially qualifies for the investigation of structural changes provoked by structural phase transitions, glass transitions and other structure-related transformations in transparent condensed matter. The scientific potential of this novel experimental technique is demonstrated by evidencing anomalies of the complex volume expansion coefficient accompanying the chemically induced glass transition occurring during the formation of a covalently cross-linked epoxy network. [less ▲]

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See detailThe catalytic influence of alumina nanoparticles on epoxy curing
Baller, Jörg UL; Thomassey, Matthieu UL; Ziehmer, Markus UL et al

in Thermochimica Acta (2011), 517

The curing process of diepoxide-triamine systems filled with water and untreated alumina nanoparticles has been investigated. The influence of both types of fillers on the curing process is very similar ... [more ▼]

The curing process of diepoxide-triamine systems filled with water and untreated alumina nanoparticles has been investigated. The influence of both types of fillers on the curing process is very similar. This is reflected by a similar shape of the heat flow (HF) and specific heat capacity curves during curing. A catalytic effect of hydroxyl groups in the water and on the nanoparticles surfaces is made responsible for the observed curing behaviour. It turns out that the strength of the catalytic effect depends on the type of filler. The described influence of alumina nanoparticles on thermoset curing is looked upon as being representative for nanocomposites consisting of epoxy thermosets and metal oxide nanoparticles without surface treatment. [less ▲]

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See detailComplex specific heat capacity of two nanocomposite systems
Sanctuary, Roland UL; Baller, Jörg UL; Krüger, Jan-Kristian UL et al

in Thermochimica Acta (2006), 445(2), 111-115

Thermal investigations on two selected model-nanocomposites have been made. They differ with regard to the type of the anorganic nanoparticles that have been filled into an organic oligomer matrix. The ... [more ▼]

Thermal investigations on two selected model-nanocomposites have been made. They differ with regard to the type of the anorganic nanoparticles that have been filled into an organic oligomer matrix. The properties of nanocomposites may vary between those of a simple mixture of independent components and those of a system, where specific interfacial interactions between the constituting parts lead to ‘new’ properties. Depending on the type of the nanoparticles filled into the matrix, the resulting properties might be closer to one or to the other extreme. We used temperature modulated differential scanning calorimetry (TMDSC) to investigate a matrix of the oligomer diglycidyl ether of bisphenol A (DGEBA) filled either with SiO2- or Al2O3-nanoparticles. The dependence of the complex specific heat capacity () on the concentration of nanoparticles shows a clear difference between the two systems as far as the glass transition of the oligomer is concerned. The SiO2 composite seems to behave more like a simple mixture, whereas the Al2O3 composite shows ‘new’ properties. [less ▲]

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