Back
Scientific Publication: Thermal characterization and diffusivity of two mono-component epoxies for transformer insulation
Our partner UC3M (Universidad Carlos III de Madrid) has published a paper about ESSIAL in the International Journal of Adhesion and Adhesives (vol. 103). The scientific publication, entitled "Thermal characterization and diffusivity of two mono-component epoxies for transformer insulation" is linked to Work Package 7.
Abstract:
The main aim of this study is the thermal characterization of an organic insulation. This insulation is a compound of two mono-component epoxy resins: Epoxylite® primer and Elmotherm® varnish. A mono-component epoxy resin usually needs a high temperature to cure; through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), non-isothermal curves are obtained, allowing the estimation of activation energies of curing and decomposition processes respectively. If Model Free Kinetic (MFK) is used from DSC curves, it is possible to simulate isothermal curves at different temperatures and times, plotting activation energy as a function of the conversion degree. The simulation from TGA curves can be used to estimate lifetime of the resins and compare them following the Toop method. DSC also allows measurement of thermal conductivity, the melting peak of metallic gallium being used for this measurement. Finally, water diffusion in resins is studied. Currently, the Materials Performance research group of UC3M is working on the European project named “Essial”, where this organic insulation is used to protect the windings and the whole transformer from the environment. The results obtained will be used to determinate the optimal operating range for this insulator, demonstrating that both epoxies are required to achieve the insulating performance of the transformer and long curing times are required for full curing of Epoxylite®.
Fig. 1. Diagram of the thermal conductivity measurement by DSC
References:
Thermal characterization and diffusivity of two mono-component epoxies for transformer insulation
Author(s): Juana Abenojar, Belen Enciso, Mariola Pantoja, Francisco Velasco, Miguel-Angel Martínez - Materials Science and Engineering and Chemical Engineering Dept, Universidad Carlos III de Madrid, Av. Universidad, 30, 28911, Leganés, Spain
Published in: International Journal of Adhesion and Adhesives Volume 103, December 2020, 102726
https://doi.org/10.1016/j.ijadhadh.2020.102726
