Military.com reports on a new “liquid body armor” additive for Kevlar vests. The research centers on polyethylene glycol, a “shear thickening” fluid (STF) with unique properties:
[Polyethylene glycol is] non-toxic, and can withstand a wide range of temperatures. Hard, nano-particles of silica are the other components of STF. This combination of flowable and hard components results in a material with unusual properties.
“During normal handling, the STF is very deformable and flows like a liquid. However, once a bullet or frag hits the vest, it transitions to a rigid material, which prevents the projectile from penetrating the soldier’s body,” said Dr. Eric Wetzel, a mechanical engineer from the Weapons and Materials Research Directorate who heads the project team.
Pretty amazing stuff…