Direct current resistivity based in-situ cure monitoring technique for amine cured epoxy resins

Abstract

The Epoxy resins and epoxy resins-based system usage in industrial applications such as composites and electronic materials keep growing. Thus, research focused on enhancing the properties of these resin-based systems is of importance for manufacturing quality controls. Especially monitoring of cure progression and chemo-rheological behavior of epoxy resins are essential for many industries. Commonly practiced cure monitoring methods such as DSC and DMA for the purpose are conducted in laboratories under specified conditions and are not practiced for real-time cure monitoring. However, in-situ cure monitoring techniques are essential for many industries as they provide more insight and thus more control over processing parameters. This study introduces a direct current resistivity-based cure monitoring method as it is simple, cost-effective, reliable, and more importantly, industry-friendly. The fast response of direct current measurements combined with the simplicity of the analysis makes this method suitable for real-time sensing applications. The strong correlation between the degree of cure and the viscosity allows us to take simultaneous measurements of both. The method's feasibility was analyzed using two amine cured epoxy resin systems.