Preparation and characterization of self-healing furan-terminated polybutadiene (FTPB) based on Diels–Alder reaction

Cracks generated in energetic composites will affect their mechanical properties and increase the risk of explosion when they are exposed to external stimuli. Therefore, self-healing properties of energetic composites have always been at the forefront of research in the field of high-performance energetic composites. Hydroxyl-terminated polybutadiene (HTPB) is a kind of binder widely used in propellants. A novel furan-terminated polybutadiene (FTPB) was synthesized by the reaction of NCO-terminated polybutadiene (IPDI-HTPB-IPDI) with furfuryl amine, and then self-healing binder films were obtained based on the DA adduct (FTPB-DA) through the reaction of furan with bismaleimide. The results show that FTPB-DA will transform into FTPB and BMI at 120 °C and recrosslinked at 60 °C to form FTPB-DA again, which gives it self-healing properties and the healing efficiency can reach 92.3%. Then, by adjusting the ratio of –NCO/–OH during the preparation process, we prepared self-healing binders with different DA adduct contents, and further studied the influence of DA adduct content on the mechanical properties and self-healing performance.