Use of Microdielectrometry in Monitoring the Cure of Resins and Composites

摘要

As thermosetting resins and composites made from them begin to be used in critical applications, it becomes necessary to monitor and analyze the cure of the resin within the confines of the processing equipment. Such measurements have been carried out using a dielectric technique called dielectrometry or dielectric analysis. Conventional dielectrometry has certain limitations associated with the use of parallel plate geometry for electrodes. For in situ measurement of cure, intrusiveness, of electrodes is a problem which may require placement of electrodes in non-strategic areas. Since electrode spacing changes during cure, it is difficult to deduce permittivity and loss factor from the data. One approach to overcome the problems described above is the development of microdielectrometry. The electrode geometry does not change, therefore loss factor and permittivity data can be deduced in real-time. Results on an aromatic amine cured epoxy resin and a dicyandiamide cured epoxy resin prepreg are presented in this report.