Thermal profiling of self-healing process simulating flight conditions. A solid-state NMR study

The self-healing polymer composites have gained increasing research interest over the past several decades and the technological interest of the most demanding industries such as aerospace, automotive and ship building industries. This study focused on the development of a thermal scanning of the self-healing progress in order to determine the thermal behavior of the self-healing agent during the thermal fatigue of a flight. The examined structure of this scenario is a protective coating (Aerowave 3003 epoxy primer) with dispersed self-healing microcapsules and catalyst Curing Solution 6007. The enclosure of the self-healing microcapsules is a mixture of an epoxy part, a diluent and a chromophore (DGEBA+ BDE+ Solvent Red 242). Our approach is to mapping the polymerization reactions during the self-healing process in real time the T2 relaxation time simulating the thermal cycles and visualizing the results in polymerization heat maps and observe the activation temperature of the self-healing process, evaluate the end of polymerization after the thermal fatigue and finally simulate the thermal path of a flight and compare the polymerization time of a static temperature scanning versus the thermal cycle. The self-healing system was tested in different temperatures (-50°C to 60°C), those temperatures were chosen due to operation environment of aerospace applications in order to understand the behavior of the self-healing process.