Nano-textiles is an emerging and interesting application of nanotechnology. It involves dealing with nano fibers at the atomic and molecular levels in order to tweak their properties. This novel technology can give rise to incredible clothing such as water-resistant and dirt-free clothes, odor-less socks and intelligent clothes that can perform climate control. As per AZoNano.com, the ever-increasing demand for sophisticated fabrics with special features and exceptional comfort drives the need for the use of nanotechnology in this industry. More and more companies are utilizing nanoadditives to enhance the surface characteristics of clothes such as water/stain-resistance, UV-protection, wrinkle resistance, color durability, flame retardancy, and better thermal performance. Although these nanofabrics are antimicrobial, strong and intelligent, they also pose some risks to the user and the environment. In the following sections, we will discuss some of their innovative applications and also environmental risks.
Nanotechnology seems to be closing in on a finding a reliable way to neutralize some chemical weapons. By weaving carbon nanotubes into clothing, a team from the National Institute of Standards and Technology (NIST) may have figured out a simple way to deconstruct nerve gases, like sarin, in moments. On a molecular level, it’s the physical shape and charge pattern of a molecule that allows it to interact with other molecules. In the case of sarin gas, its shape gives it devastatingly toxic properties. Exposure to sarin, either by inhalation or contact with the skin, causes the neurotransmitter acetylcholine to build up in the nervous system, which makes muscles seize up. When this effect reaches the diaphragm and other muscles responsible for breathing, asphyxiation is not far behind. The key to deconstructing sarin and similar organophosphate compounds is breaking the P-F bond, and this is what the NIST team has figured out how to do with specially treated carbon nanotubes. Catalyzing the breakdown of sarin is not difficult in a laboratory setting, but doing so passively in a real world situation is the challenge, thus carbon nanotubes are the perfect solution. They are lightweight, durable, and have high surface area relative to volume. This allowed the researchers to coat nanotubes with a catalytic polymer compound known as a copper-chelating bipyridine. When sarin comes in contact with these compounds, the P-F bond is hydrolyzed (broken) and its deadly effects are neutralized. Working with real sarin gas was not only dangerous, but also unnecessary. The researchers instead performed their experiments on a safe molecule that contained the same P-F bond that is the weak point of sarin. They used UV-vis spectroscopy to monitor the breakdown rate of the molecule when exposed to the treated carbon nanotubes, finding that it was breaking bonds approximately 63 times faster than sarin’s natural decay rate. If clothing and other materials had these nanotubes woven in, it could easily be the difference between lethal exposure and a survivable incident for the victims of poison gas attacks. The researchers see this as a perfect approach to creating self-decontaminating materials, which would be a boon to those tasked with cleaning up after an organophosphate accident or attack. These gasses often become embedded in fabrics, allowing them to be re-dispersed later. Now it is a matter of determining whether the nanotubes are more effective when coated with the reactive polymer before or after being incorporated into fabrics. It may also be possible to tweak the formulation and coating process to make the polymer even more reactive, which may break down organophosphates more quickly. It will be some time before such a material can be made safe, comfortable for the wearer, and somewhat affordable.
Carrying enough juice to power your MP3 player, smart phone and electric car in the fabric of your jacket may become a reality thanks to breakthrough technology developed at a University of Central Florida research lab. Nanotechnology scientist and professor Jayan Thomas and his Ph.D. student Zenan Yu have developed a way to both transmit and store electricity in a single lightweight copper wire. Copper wire is the starting point but eventually, Thomas said, as the technology improves, special fibers could also be developed with nanostructures to conduct and store energy.
More immediate applications could be seen in the design and development of electrical vehicles, space-launch vehicles and portable electronic devices. By being able to store and conduct energy on the same wire, heavy, space-consuming batteries could become a thing of the past. It is possible to further miniaturize the electronic devices or the space that has been previously used for batteries could be used for other purposes. The team began with a single copper wire. Then he placed a sheath over the wire made up of nanowhiskers the team grew on the outer surface of the copper wire. These whiskers were then treated with a special alloy, which created an electrode. Two electrodes are needed for the powerful energy storage. So they had to figure out a way to create a second electrode. They did it by adding a thin plastic sheet around the whiskers and wrapping it around using a metal sheath after generating nanowhiskers on (the second electrode and outer covering). The layers were then glued together with a special gel. Because of the insulation, the inner copper wire retains its ability to channel energy, but the layers around the wire independently store powerful energy. In other words, Thomas and his team created a supercapacitor on the outside of the copper wire. Supercapcitors store powerful energy, like that needed to start a vehicle or heavy-construction equipment.
Although more work needs to be done, Thomas said the technique should be transferable to other types of materials. That could lead to specially treated clothing fibers being able to hold enough power for big tasks.