Dielectric properties of an epoxy-amine system at a high microwave frequency
Autor: | Leo C. Kempel, Liming Zong, Nikki Sgriccia, Rensheng Sun, Shuangjie Zhou, Martin C. Hawley |
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Rok vydání: | 2005 |
Předmět: |
Arrhenius equation
Diglycidyl ether Materials science Polymers and Plastics Thermodynamics General Chemistry Rate equation Epoxy Dielectric Atmospheric temperature range chemistry.chemical_compound symbols.namesake chemistry visual_art Polymer chemistry Materials Chemistry visual_art.visual_art_medium symbols Dielectric loss Curing (chemistry) |
Zdroj: | Polymer Engineering & Science. 45:1576-1580 |
ISSN: | 1548-2634 0032-3888 |
Popis: | The dielectric properties of a curing diglycidyl ether of bisphenol A (DGEBA)/Jeffamine D-230 system have been studied over the temperature range of 20–90°C at 2.45 GHz. It was found that, generally, both the dielectric constant and the dielectric loss factor of the system increased with temperature and decreased as the reaction proceeded. The epoxy resins at different extents of cure exhibited the γ relaxation, which can be described by the Arrhenius Rate Law. The relaxation is attributed to the motions of the dipolar groups associated with the reactants. The Davidson-Cole model can represent the temperature dependencies of the dielectric properties. The nature of the information yielded by dielectrometry on the dynamics of the system is discussed. The evolution of the parameters of the models during the polymerization was mainly affected by the decreasing number of the dipolar groups involved in the reaction and increasing medium viscosity. POLYM. ENG. SCI. 45:1576–1580, 2005. © 2005 Society of Plastics Engineers |
Databáze: | OpenAIRE |
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