This technology is a biologically inspired 3D microvascular networks within composite materials provide damage management and active temperature regulation.
Details
A novel fabrication of microvascular structural material.
Imagine a responsive material that has the ability to react to physical changes by delivering a functional fluid to vital, often inaccessible areas. In nature, this is accomplished through complex vasculature that transports vital fluids to tissues throughout an organism in order to regulate temperature, deliver nutrients, or begin the healing process. Scientists at the University of Illinois have taken their cue from such biological systems in fabricating a 3-dimensional vascular network within a polymer or polymer composite material that can be filled with virtually any fluid. The process is rapid, scalable and easily integrated into existing manufacturing processes with commercially available precursors. In the materials world, this system has the potential to help create longer lasting, safer and fault tolerant products. Through chemical decomposition of the sacrificial fiber relative to the matrix, the original fiber is removed from the matrix leaving behind a pervasive 3D interconnected network of microchannels that can be filled with a fluid either by using capillary action or by pumping. The choice of fluid can impart functionality to the matrix material such as self-healing, temperature regulation, or imparting visibility to areas where damage occurred through the use of a conspicuous dye. These microvascular composite materials can distribute these active fluids for reactions within the matrix in areas that are normally problematic to reach within components.
The sacrificial fibers can be handled simultaneously with reinforcing fibers and decompose upon exposure to an external trigger such as processing temperature. This novel material system has the potential to restore structural integrity and extend the safety, reliability and operating life of countless components that are used everyday in numerous industry applications. For example, composite materials play an integral role in everything from aerospace and automotive applications to building materials and must maintain their integrity after repeated thermo-mechanical loading. Under such conditions, micro-cracks can develop over time within the structure significantly weakening its strength. Incorporation of a self-healing capability within the composite can instantly and permanently repair the damage, allowing the composite to retain its structural and mechanical integrity and prolonging its operational life. Figure 1: Creation of 3-D microvascular network. (A) 3-D woven preform, (B) integration of sacrifical fibers, (C) Resin infusion, (D) 3D woven composite and (E) formation of 3-D microvascular network.
Applications
This novel material system has the potential to restore structural integrity and extend the safety, reliability and operating life of countless components that are used everyday in numerous industry applications. Composite materials play an integral role in everything from aerospace and automotive applications to building materials and must maintain their integrity after repeated thermo-mechanical loading. Under such conditions, micro-cracks can develop over time within the structure significantly weakening its strength. Incorporation of a self-healing capability within the composite can instantly and permanently repair the damage, allowing the composite to retain its structural and mechanical integrity and prolonging its operational life. Rubber and latex industries could use this material to make improvements to existing products making them safer and longer-lasting. A self-healing tire would significantly increase safety on the road as well as reduce replacement costs. A self healing hose in air brakes for trains and trucks would significantly diminish the catastrophic risk of a failure to the brake system. Latex gloves are the primary barrier between a caregiver and possible infectious agents and tears and puncture can happen without the wearers knowledge.
Using this microvascular material filled with a conspicuous dye would alert the wearer of a tear sooner. Alternatively, an anti-infective agent could be used and in the event of a tear or puncture, this agent would be released and help prevent infection. Although lithium ion batteries are gaining attention for use in automotive applications, their performance suffers at high temperatures, which are associated with quicker discharge and safety hazards. They must come with sophisticated battery management systems to maintain the proper temperatures in cars. Battery pack housing would benefit from the incorporation of a 3D microvascular material containing a temperature regulating fluid within the capillaries dissipating heat from hot spots and helping to maintain the proper thermal conditions for optimal battery life. Similarly, as computer technology moves to high-density storage and ultra-fast processing, thermal management becomes an issue. By integrating a microvascular material with a liquid capable of absorbing heat, one could create an effective and compact thermal management system for high density computational applications.
Benefits
Provides 3-D microvascular network for self-healing or active temperature regulation
Process is scalable and can be woven into large mats
All components of process are commercially available