Ultrasonics for accelerating the implementation of next-generation self-healing polymers

Next-generation polymers aim to incorporate advanced functionalities such as self-healing and shape memory, along with the use of bio-based matrices. Among them, self-healing polymers are gaining prominence due to their ability to recover structural integrity after damage, enhancing the durability, lifespan, and performance of components. However, optimizing the self-healing process typically requires destructive testing at multiple temperatures, which consumes time, materials, and introduces uncertainty. To address this, a non-destructive ultrasonic method was developed to monitor and characterize self-healing polymers in real time. This technique was applied to thermoset/thermoplastic polymer matrices with different compositions, evaluating how the weight fraction of the thermoplastic influences sound velocity during curing, and thus, mechanical behavior and phase separation—factors directly linked to self-healing performance. Additionally, blends of bio-based epoxy and thermoplastic were studied to assess mechanical properties after multiple healing cycles. The method optimized self-healing temperature, enabling reliable restoration verification in-service, where direct assessment is otherwise challenging. By reducing the need for destructive tests and enabling real-time assessment, this ultrasonic approach offers a powerful tool for accelerating the development of self-healing polymers. Its application is especially relevant in demanding fields such as aerospace, where efficiency and reliability play a critical role.