Glass fiber and other reinforced composite fiber materials are lightweight and sturdy and are widely used in aerospace, automotive, marine, urban construction and sports equipment. However, since they are layered structures, interlayer separation may occur, and once internal damage occurs, it is difficult to detect and cannot be repaired by conventional methods. This is one of the important reasons for limiting the wider use of composite materials.
Recently, the Beckman Institute Autonomous Materials System (AMS) research team at the University of Illinois at Urbana-Champaign developed a new self-healing system, like the vascular network in biological tissues, filled with chemical healing. Liquid, which helps strengthen the fiber material for repeated automatic healing. This self-healing system is promising in addressing long-term risk issues, extending material life and improving reliability. Related papers were published in the recently published Advanced Materials magazine.
The self-healing system is a three-dimensional vascular network. The researchers used environmentally friendly polymers to make "wires", "sewing" the reinforced fiber materials, and sewed a three-dimensional pattern of special textures, just like the vasculature in biological tissues. This sewing thread is temporary and is evaporated by heating after processing to leave only a hollow network of vessels. The vessel consists of two isolated vasculatures, each filled with a different healing agent, one epoxy resin and the other a hardener.
"When a fracture occurs, the originally isolated micro-pipe system breaks, and the healing agent inside flows out into the fiber material. Like the rupture of the blood vessel, the two healing agents contact each other at the fracture site, forming a polymer, like a structure. Sexual glue, connecting the damaged areas together. We conducted multiple cycles of testing, and basically all the fractures were 100% successfully healed.” The first author of the paper, Jensen Padrik, said, “This self-healing method The advantage is that we don't have to probe the material structure, find out where the damage is, and manually fix it."
“This is the first time to demonstrate the automatic healing of repeated cycles in reinforced composite fibers.” Scott White, one of the authors of the paper and aeronautical engineering professor, said, “In the past, automatic healing was also demonstrated in high-polymer materials, but that’s Different technologies cannot be used in reinforced fiber composites. The vascular technology we developed makes up for the missing part of the middle."
Nancy Sotos, a professor of materials science and engineering, also pointed out: "The seamless integration of this vascular system with the process of manufacturing polymeric materials is also very useful in commercial applications. prospect."