Thermoplastic-modified epoxy resins cured with different functionalities amine mixtures. Kinetics and miscibility study
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The kinetics of a poly(methyl methacrylate) (PMMA)-modified epoxy resin cured with different functionalities amine mixtures was analyzed using differential scanning calorimetry (DSC) in both isothermal and dynamic conditions. A delay in the reaction rate was observed which increased with PMMA content. An approach of kinetic features involved in curing was carried out. A linear dependence of preexponential factors of neat systems with modifier content was considered. The approach shows the contribution of other factors including the dilution effect of the functional groups to the observed delay. Fourier transform infrared spectroscopy (FTIR) indicated a noticeable change in the interactions present in neat systems due to the presence of PMMA. On the other hand, a significant influence of the ratio between each amine in the epoxy/amine mixtures on the final physical appearance was observed. At constant curing conditions, materials from completely opaque (phase separated) to transparent (miscible) were obtained with the increase in monoamine content.
KeywordsDifferential scanning calorimetry Functionality Kinetics Reaction-induced phase separation Thermosets
M. Blanco wishes to thank University of the Basque Country (UPV/EHU) for her Ph. D. grant. C. C. Riccardi thanks Gobierno Vasco/Eusko Jaularitza for its financial support. The authors also wish to express their gratitude to Ministerio de Educación y Ciencia/Feder (MAT2006-06331 project) and Eusko Jaularitza/Gobierno Vasco (IT-365-07 Grupos Consolidados).
- 1.Williams RJJ, Rozenberg BA, Pascault JP. Reaction-induced phase separation in modified thermosetting polymers. Adv Polym Sci. 1997;128:95–156.Google Scholar
- 13.Wisanrakkit G, Gillham JK, Enns JB. Modeling reaction kinetics of an aminecured epoxy system at constant heating rates from isothermal kinetic data. Polym Mat Sci Eng. 1987;57:87–91.Google Scholar
- 23.Fox TG. Influence of diluent and of copolymer composition on the glass temperature of a polymer system. Bull Am Phys Soc. 1956;1:123.Google Scholar
- 38.Blanco M, López M, Álvarez de Arcaya P, Ramos JA, Kortaberria G, Riccardi CC, et al. Thermoplastic-modified epoxy resins cured with different functionalities amine mixtures. Morphology, thermal behaviour and mechanical properties. J Appl Polym Sci. (in press).Google Scholar