Summary Polymers have a great interest for the study and design of new materials. Among these materials are epoxy resins, that have good properties, such as low shrinkage during cure, good adhesion, high water and chemical resistance, etc. They have also fast and easy cure in a broad range of temperatures. TTT diagrams are very helpful to design new epoxy materials as they allow the search for very important final properties, such as thermal stability, conversion or glass transition temperature of a material cured through a selected curing cycle. In this work the dependence of the thermal stability on the selected curing cycle for a DGEBA/1,2 DCH system was studied.
Authors:Maria Villanueva, I. Fraga, J. Rodríguez-Añón, J. Proupín-Castiñeiras, and J. Martín
The diffusive, calorimetric and thermal degradation behavior of different
epoxy-amine systems was investigated during water sorption at different temperatures
(23, 40 and 70°C). Experimental results showed that the water absorption
at these temperatures fitted well to Fick’s law. Influence of water
immersion during different periods of time on the glass transition temperatures
was studied by differential scanning calorimetry. Thermal degradation of saturated
samples was studied by thermogravimetric analysis. Dependence on the selected
curing cycle was also checked.
Authors:M. Villanueva, J. Martín-Iglesias, J. Rodríguez-Añón, and J. Proupín-Castiñeiras
The thermal degradation of the epoxy system diglycidyl ether of bisphenol A (DGEBA n=0) and m-xylylenediamine (mXDA) containing different concentrations of polyhedral oligomeric silsesquioxanes (POSS) nanoparticles was studied by thermogravimetric
analysis in order to determine the influence of both, the POSS concentration and the curing cycle on the degradation process
and to compare it with the results for the non modified system.
Glass transition temperatures for the same systems were also determined by differential scanning calorimetry. Different behaviors
have been observed, depending on the POSS concentration and on the curing selection.
Authors:L. Núñez-Regueira, M. Villanueva, and I. Fraga-Rivas
study of the degradation of a polymer is important because it can determine
the upper temperature limit, the mechanism of a solid-state process, and the
life-time for this system. Since the behavior of thermosets is affected by
the selection of the curing cycle, it is important to investigate the changes
which take place during the thermal degradation of these materials when a
change on the sequence of time and temperature is introduced during the curing
this work, the thermal degradation of two epoxy systems diglycidyl ether of
bisphenol A (BADGE n=0)/1, 2 diamine cyclohexane
(DCH) cured through different sequences of time and temperature was studied
by thermogravimetric analysis in order to determine the reaction mechanism
of the degradation processes, and also to check the influence of the curing
cycle on this mechanism. Values obtained using different kinetic methods were
compared to the value obtained by Kissinger’s method (differential method
which do not require a knowledge of the n-order
reaction mechanism), and to that obtained through Flynn–Wall–Ozawa
method in a previous work.
section. During a partial curecycle, the resist collapses under the surface tension of the flowing material and forms a curved shape which can be used as a template for advanced shapes (e.g., curved metal contacts for compliant interconnects) ( Fig. 13
Authors:Omid Zabihi, Abdollah Omrani, and Abbas Ali Rostami
in analytical grad.
Sample preparation and curingcycle selection
To prepare the composites a specific level of nanoalumina was added into epoxy matrix before adding the curing agent at stoichiometric ratio. In a
Authors:S. M. Sabzevari, S. Alavi-Soltani, and B. Minaie
) tape, manufactured by Cytec Engineered Materials (USA) was used in this study. This thermoplastic toughened epoxy resin prepreg is formulated for autoclave or press molding. The manufacturer recommended curecycle for 977-2 UD is isothermal cure at 177
Authors:Zhuofeng Liu, Jiayu Xiao, Shuxin Bai, and Weijun Zhang
, Cottu JP , Marinez JJ , et al. Optimisation of curecycle parameters for a carbon epoxy laminate . 2nd international conference on deformation and fracture composites, Manchester; 1993. p. 29 – 31 .
Authors:María González González, Juan Carlos Cabanelas, Javier Pozuelo, and Juan Baselga
fragile solid. This result indicates that the reactivity of the secondary amine towards the oxirane group of ECC is very low below 120 °C, and remains low even at 190 °C, leading to a long curingcycle. Since it is not possible to cure at higher