Comparative study of continuous‐power and pulsed‐power microwave curing of epoxy resins

Three epoxy reaction systems, diglycidyl ether of bisphenol A (DGEBA) with curing agents meta phenylene diamine (mPDA), diaminodiphenyl methane (DDM), and diaminodiphenyl sulfone (DDS), were cured with both pulsed‐power and continuous‐power microwave curing systems. Isothermal curing was conducted at three different temperatures for each reaction system with both pulsed‐power and continuous‐power microwave curing systems. Extent of cure was measured with Fourier Transform Infrared Spectroscopy (FTIR). The temperature characteristics, incident and reflected power patterns, and the reaction rates were compared between the two curing approaches. The incident power and reflected power of both curing processes were observed to reveal reaction status. Continuous‐power microwave curing produced noticeably higher reaction rates than pulsed‐power microwave curing.