Researchers have discovered that composites made of two or more materials whose stiffness and flexibility are structured in very specific ways, could lead to better protection against impacts from bullets and other high-speed projectiles than lightweight material such as Kevlar.
The team of researchers from MIT and Rice University developed a self-assembling polymer with a layer-cake structure: rubbery layers, which provide resilience, alternating with glassy layers, which provide strength.
They then developed a method for shooting glass beads at the material at high speed by using a laser pulse to rapidly evaporate a layer of material just below its surface. Though the beads were tiny — just millionths of a metre in diameter — they were still hundreds of times larger than the layers of the polymer they impacted: big enough to simulate impacts by larger objects, such as bullets, but small enough so the effects of the impacts could be studied in detail using an electron microscope.
Their work could accelerate progress on materials for applications in body and vehicle armour; shielding to protect satellites from micrometeorite impacts; and coatings for jet engine turbine blades to protect from high-speed impacts by sand or ice particles.
The results of the research are reported in the journal Nature Communications.