Fiberglass and other fortified composite fibre materials are lightweight and widely used in aviation, automobiles, navigation, urban buildings and sporting equipment. However, because they are layered structures, there may be layers of separation, once the internal damage is difficult to detect, and can not be repaired with traditional methods. This is one of the important reasons restricting the wider application of composites.
Recently, the University of Illinois at Urbana-Champagne, the Baccman Institute of Autonomous Materials System (AMS) research team developed a new self-healing system, like the biological tissue of the vascular network, in which the chemical healing fluid, can help strengthen the fiber material to achieve repeated automatic healing. This self-healing system is promising to address long-term risk problems, prolong material life and improve reliability. The relevant papers are published in the recently published "Advanced Materials" magazine.
The self-healing system is a three-dimensional vascular network. The researchers used environmentally-friendly polymer to make "line", to strengthen fiber material "sewing processing", sewing out special texture three-dimensional pattern, like biological tissue in the vein tube system. And this sewing thread is temporary, after processing is completed by heating it evaporates, leaving only the hollow pulse tube network. The vein tube consists of two isolated vein tube systems, which are charged with different healing agents, one is epoxy resin and the other is hardening agent.
"When the fracture occurs, the isolated micro-piping system breaks, the healing agent inside the flow out into the fiber material, as the blood vessel rupture, two healing agents in the fracture position contact each other, will form a polymer polymer, like a structural glue, the damage area connected together." We conducted a number of cyclic tests, and basically all the fractures were able to heal successfully 100%. "The advantage of this self-healing approach is that we don't have to explore the material structure, find out where it hurts, and manually fix it," said Jason Padrick, the first author of the paper. "
"This is the first time to demonstrate the automatic healing of recurrent cycles in the enhanced composite fibers." "One of the authors of the paper Communications, aviation engineering Professor Scott White said," In the past has demonstrated the high poly material has also been automatic healing, but that is different technology, can not be used in the reinforced fiber composites. " The Pulse-tube technology we developed compensates for the missing link in the middle. "
Nancy Sotos, one of the authors of the paper, the professor of material science and engineering, also pointed out that "seamless integration of the pulse tube system and the process of producing polymeric materials is also promising in commercial applications." "