The highly breathable membranes have pores made of a few nanometer-wide vertically aligned carbon nanotubes that are surface modified with a chemical warfare agent-responsive functional layer.Jacqueline McBride/LLNL
From left, Kuang Jen Wu and Francesco Fornasiero look on as Sangil Kim holds a piece of the nanotube fabric that repels chemical and biological agents.Jacqueline McBride/LLNL
Soldiers may ‘asp’ for it by name.
Lawrence Livermore National Laboratory has created a new material for military uniforms that can automatically repel chemical and biological agents -- and shed contaminated layers like a snakeskin.
The new cutting-edge fabric, which is made from tiny carbon nanotubes, has pores just a few nanometers wide. When a warfighter encounters a chemical or biological attack, the fabric switches from resting into a protective state, closing those pores to block the attack.
As an added defense mechanism, this second skin will peel off or shed the contaminated surface layer, like a snake shedding its skin. Just as human skin responds to threats, so too will the fabric exfoliate in reaction to chemical agents.
"The uniform will be like a smart second skin that responds to the environment," said Francesco Fornasiero, LLNL's principal investigator for the project.
The new material’s pores are made from vertically aligned carbon nanotubes. The surface of the nanotubes is modified with a “functional layer” that is responsive to chemical warfare agents.
Since the pores are already incredibly tiny, just a few nanometers across, they will successfully block biological agents like viruses or bacteria that are approximately 10 nanometers.
Blocking smaller chemical agents is tougher, however, meaning the membrane pores need to be smart and react.
The team is therefore modifying the original prototype to include “functional groups” with the ability to sense and then block these threat. Lawrence Livermore Laboratory describes these groups as gatekeepers at an entrance.
The fabric will stop attacks from blister agent sulfur mustard and VX nerve agents through to toxins and even biological spores like anthrax. Yet it can breathe, important to reduce the risk of heat fatigue and stress.
Conventional protective military uniforms take a passive approach: heavyweight full-barrier protection or absorptive over-garments work but they’re cumbersome and hot.
The team says they have successfully demonstrated breathability in their prototype membranes, in spite of the tiny pore size. The carbon nanotube pores are two orders of magnitude faster at transporting gas than ordinary pores, boosting breathability in the ground-breaking composite material.
The five-year, $13 million Defense Threat Reduction Agency project is led by Lawrence Livermore in collaboration with the Massachusetts Institute of Technology, Rutgers University, University of Massachusetts-Amherst, Natick Soldier Research Development and Engineering Center and Chasm Technologies Inc.
Ballet dancer turned defense specialist Allison Barrie has traveled around the world covering the military, terrorism, weapons advancements and life on the front line. You can reach her at firstname.lastname@example.org or follow her on Twitter @Allison_Barrie.