(Rice.edu) — In the macro world, it’s easy to see what happens when a bullet hits an object. But what happens at the nanoscale with very tiny bullets?
A Rice University lab, in collaboration with researchers at the Massachusetts Institute of Technology and its Institute for Soldier Nanotechnologies, decided to find out by creating the nanoscale target materials, the microscale ammo and even the method for firing them.
In the process, they gathered a surprising amount of information about how materials called block copolymers dissipate the strain of sudden impact.
The goal of the researchers is to find novel ways to make materials more impervious to deformation or failure for stronger and lighter body armor, jet engine turbine blades for aircraft, and for cladding to protect spacecraft and satellites from micrometeorites and space junk. Their work was detailed in the online journal Nature Communications.
The group was led by Rice materials scientist Ned Thomas, the William and Stephanie Sick Dean of Rice’s George R. Brown School of Engineering, and Rice research scientist and lead author Jae-Hwang Lee.
The researchers were inspired by their observations in macroscopic ballistic tests in which a complex multiblock copolymer polyurethane material showed the ability to not only stop a 9 mm bullet but also seal the entryway behind it.
“The polymer has actually arrested the bullet and sealed it,” Thomas said, holding a hockey puck-sized piece of clear plastic with three bullets firmly embedded. “There’s no macroscopic damage; the material hasn’t failed; it hasn’t cracked. You can still see through it. This would be a great ballistic windshield material.
“We want to find out why this polyurethane works the way it does. Theoretically, no one understood why this particular kind of material – which has nanoscale features of glassy and rubbery domains – would be so good at dissipating energy,” he said.