Curing Kinetics of T300 Carbon Fiber/Epoxy Resin Prepregs Investigated by Differential Scanning Calorimetry

Understanding and quantifying the curing kinetics of carbon fiber/epoxy prepregs is critical for optimizing manufacturing processes and ensuring structural integrity in high-performance composites. In this work, the non-isothermal and isothermal curing behaviors of T300 carbon fiber/epoxy resin prepregs were systematically studied via differential scanning calorimetry (DSC). Activation energies and kinetic parameters were derived using the Kissinger, Ozawa, and Friedman model-free approaches, revealing both global and conversion-dependent kinetic behavior. The Málek method confirmed that the curing reaction follows an autocatalytic mechanism consistent with the Sestak–Berggren model. Under isothermal conditions, increasing temperature would significantly accelerate the curing rate, and the curing behavior was well captured by a diffusion-modified Kamal model. The combined kinetic modeling provides a comprehensive understanding of the reaction mechanism, enabling more accurate simulation of curing behavior and guiding the design of optimized curing cycles for aerospace-grade thermoset composites.