According to a new study by the US Army, the materials used for personal protective equipment for soldiers may also be strong enough for vehicles. The research published in the "Polymer" magazine "Findings" on April 10 showed that filling carbon nanotubes in polymers could potentially improve the energy dissipation of driverless cars.
A team led by the Army Research Laboratory of the US Army Combat Capability Development Command is conducting theoretical research through computer modeling. Researchers say that polyurethane is a material for many purposes, including coatings, foams and solid elastomers. For example, as film adhesives, they are commonly used as adhesives between glass layers, as well as polymer backing in transparent glass or plastic composites, such as visual blocks on side windows of tactical vehicles. In particular, high-performance segmented PUU polymers have various physical and mechanical properties.
In this study, the research team used computer modeling to study the properties of the material. Sliozberg said that for military vehicles, layered composite materials are a promising field of research, because they are not easy to corrode, which leads to premature failure of components.
"Compared with traditional thermosetting composite materials, polyurethane urea elastomers are much less brittle and can provide unparalleled control of the material structure." Sliozberg said carbon nanotube / polymer composite materials have ideal electrical Thermal properties show better performance than traditional fiber materials. "
Sliozberg said they need to have a deeper understanding of the nature of the molecular-level interactions in these materials to enhance the maximum stress level it can withstand and adjust the energy dissipation mechanism. The chemical modification of nanofillers is very important, usually by changing its structure and chemical properties to reduce its performance. For example, Young's modulus may be lower.
The team's research results strongly indicate that the microstructure of the multiphase polyurethane polymer can be optimized by adding oriented carbon nanotubes to the matrix and interface without any filler surface modification.
"This shows that the high affinity of polyurethane-urea for carbon nanotubes will lead to a new green synthetic route without the need for any surface functionalization of nanotubes to prepare carbon nanotube-reinforced polyurethane- Urea nanocomposites. ”The co-authors of Sliozberg ’s paper“ Dynamic Simulation of Dissipative Particles in Microphase Separation of Polyurethane-Urea Nanocomposites ”are Dr. Jeffrey L. Gair Jr., Cinematics, Inc. and Dr. Alex J. Hsieh, who From the Lab Soldier Nanotechnology Institute of MIT.
The structural materials of military vehicles may be improved in the future, because they are less corrosive, lighter, and more conductive than traditional elastomers. These materials also show great potential to protect vehicles from static electricity accumulation, discharge and lightning strikes. The collaborators of Drexel University are conducting further research. They have studied the potential application of PUU polymer with carbon nanotubes as a filament material for 3D printing. The laboratory is currently not conducting these studies on any vehicles. The researchers plan to collaborate with other Army teams in the near future for testing.