Mechanical Behavior of Aramid Nanofibers and Nanocomposites
Abstract
It is well known that density of defects drives failure and that a reduction of fiber diameter can lead to significant gain in material strength. The proposed research would seek to perform a fundamental investigation of recently identified aramid nanofibers (ANFs) as a reinforcing material to elucidate the strength and stiffness of the individual fibers as a function of dimension and to correlate the measurements to bulk aramid fibers (Kevlar). While electrospinning has been widely used to study nanoscale polymeric fibers, this processing approach provides little control over drawing and the structure of the final material, ultimately producing mechanical properties inferior to their microscale counterparts. It can be expected that the disassembly into nanometer scale Kevlar fibers without the complete dissolution of the polymer into individual chains should yield equally high or better strength, stiffness and toughness as the micro-scale fiber therefore offering an ideal material to elucidate the mechanical properties of pristine nanoscale crystals of high strength polymers. ANFs have great potential to be used as reinforcement, however cannot be effectively applied since their mechanical properties are not understood. This effort will perform mechanical testing of the individual ANFs as a function of dimension and will correlate the measured properties of the individual ANFs to the bulk properties observed in nanocomposites. Furthermore, the use of commercially manufactured materials as the feedstock to nanofiber production will ensure that our measurements are from the highest grade polymers and will reduce potential risk in the processing of high quality nanostructures, thus maximizing fundamental information impact. The ultimate goal is to provide a better understanding of nanoscale polymeric reinforcements such that optimal material behavior can be achieved and to provide a foundation for the further development of this class of materials, which may alleviate many of the challenges posed by current nanoscale reinforcements.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 22, 2019
- Source ID
- W911NF1810061
Entities
People
- Henry A Sodano
Organizations
- Army Contracting Command
- United States Army
- University of Michigan