Cure kinetics characterization and monitoring of an epoxy resin for thick composite structures
The use of fiber-reinforced polymers (FRPs) is increasing for numerous industrial applications. In-situ cure monitoring is very important to directly observe the cure process of FRPs during the manufacturing process. In this work, the possible use for in-situ cure monitoring of an epoxy resin was investigated by means of Raman spectroscopy and dielectric analysis (DEA). The cure behavior was first characterized using differential scanning calorimetry (DSC) as a baseline comparison, and the best-fit phenomenological reaction model was determined to describe the cure behavior of the epoxy resin as well as the kinetic parameters. The relationship between Tg and degree of cure was also established. The degree of cure obtained from the Raman spectroscopy and DEA under isothermal conditions was compared to the one obtained from the DSC. A good agreement was observed among the three methods, supporting in-situ cure monitoring during manufacturing. An implementation plan for in-plant monitoring was also discussed.