This research presents a single-walled carbon nanotube (SWCNT)-enabled real-time monitoring system to optimize postcuring conditions (temperature and duration) for epoxy resin. This method can serve as an alternative to traditional methods like Differential Scanning Calorimetry (DSC), which is effective in measuring the degree of cure in polymers during industrial curing (manufacturer-recommended cure cycle). Two different programs using SWCNTs were employed to design the cure cycles for investigating the development of mechanical properties: Program A as the comparison of effects of varied duration of high-temperature curing and Program B as high-temperature curing followed by the varied duration of low-temperature post-curing. By correlating variation in the electrical resistance of SWCNT with curing stages, we illustrate that extending post-curing at 100 °C for 24 h after an initial 3-h cure at 130 °C increases (i) tensile strength by 60% and ultimate tensile elongation by 101% and (ii) shear strength by 14% and ultimate shear elongation by 16% compared to industry standards. This approach not only improves mechanical performance but also enables precise, non-destructive cure-state detection, offering a scalable solution for high-performance composites in the aerospace and automotive sectors.

Real-time cure monitoring via carbon nanotube networks enables mechanical property optimization in post-cured epoxy resins
    Abstract
    1 Introduction
    2 Mechanism of electrical conductivity in CNTpolymer nanocomposites
    3 Materials and methods
        3.1 Materials
        3.2 Sample’s fabrication
            3.2.1 Cure monitoring samples
            3.2.2 Tensile and shear test’s samples
        3.3 Mechanical tests
    4 Results and discussion
        4.1 Program A and B: tensile test
        4.2 Program B: shear test
    5 Discussion
        5.1 DSC vs SWCNTs’ sensor
        5.2 Microstructural evolution of the composite under different curing conditions
    6 Conclusion
    References

• M. Jafarypouria(Skolkovo Institute of Science and Technology, Moscow, Russia) Corresponding author
• B. Mahato(Skolkovo Institute of Science and Technology, Moscow, Russia)
• S. G. Abaimov(Skolkovo Institute of Science and Technology, Moscow, Russia)