Researchers have created an alleged copolymer polyurethane “super material” that could potentially be the future of bulletproof technology, particularly in vehicles. Results have so far been positive, with lab tests showing the material capable of stopping 9-millimeter bullets in their path without any macroscopic damage whatsoever. Of particular interest, besides its incredible ability to dissipate energy, is the polyurethane’s ability to seal the point of entry.
The particular polyurethane, according to Ned Thomas, dean of the George R. Brown School of Engineering at Rice University, actually contains nanoscale features of both glassy and rubbery domains, giving it a structure that’s more impervious to deformation. Experimentally it works — though no field tests have been performed — but you can imagine the possibilities for soldiers and police. (Or what about as a smartphone screen?)
Amazingly, the material is said to “self-assemble” into alternating 20 nanometer layers of polymer when created, and actually melts into a homogeneous liquid upon impact by high velocity projectiles. This is why, when shot with a 9-millimeter bullet, the material essentially sealed the entryway behind it, and showed no visible failure or cracking.
The team tested their materials in two ways: horizontally, with the impact perpendicular to the micro grain, and vertically, straight into the layered edges. They found the horizontal material best at stopping projectiles, perhaps because the layers reflect part of the incident shock wave. Beyond the melt zone in front of the projectile, the layers showed the ability to deform without breaking, which led to improved energy absorption.
Thomas and his team eventually hope their findings, along with studies of other nanostructured materials, will “accelerate the design of metamaterials with precise control of their nano- and microstructures for a variety of applications.”