Fabrics are used everywhere in the world. Whether it be your son’s t-shirt with a custom iron on patches or your socks or even the packaging material, all use some sort of fabric. A news from April 29th which was about Boeing 747 cargo jet crashing on to Bagram Airbase. The cause of crash was that the netting fabric did not keep the pallets of denim from moving around. Movement of those pallets caused some instability issues resulting in the crash. Different kinds of fabric have been used for several centuries. Man-made fibers were an invention of the 19th century and since then a lot of new materials have been created with a varied areas of usage in the modern society. Polyester is one such fiber which found its application in nearly all walks of life including the industrial applications where it is used for conveyor belts, strengthening material, seat belts, for securing loads and so much more. Currently, all netting fabric is made from polyester, but the new type of fabric is making an attempt to replace polyester and it is currently used by very few airline companies.
This new fabric we are talking about is made from “ultra-high-molecular-weight polyethylene” (UHMWP). All plastics are long chains of hydrocarbons which give them the property of plasticity. Similarly, UHMWP has heavy and long chains of hydrocarbons having strength to weight ratio several times that of steel. To be precise the steel has a specific strength of 254 kN.m/kg, and the UHMWP has a specific strength of 3810 kN.m/kg!
High strength fibers have always been in demand by the industry. To produce these fibers requires some great material engineering. A Japanese firm, Kuraray has developed the property of some polymers to form into crystals. Polymers which form into crystals are definitely stronger than polymers. We are talking about Liquid crystal polymers which are paving their way in the industry and getting known for several reasons, one of them being strength! By melting these liquid crystal polymers to 300 degrees Celsius and then pumping them through fine holes of size 23 micrometers, we get some fine fibers. Twisting about hundred thousand of those fine fibers would give us something of the size bigger than a pencil and it is capable of holding 8 tons of weight suspended! They are known by the brand name Vectran and are known for strength.
Another kind of fabric known as auxetic yarn is rather unusual. A usual yarn would become thin when stretched, while this yard becomes thicker. Advanced Fiber Technologies based in Houston is working on implementing this yarn into bulletproof vests. Combined with Kevlar and Hytrel the new product aims at bouncing off shrapnel because of the inherent property of the material. The product is still under development and tests. Commercially they have brand named the fabric as Xtegra. Auxetic fiber is paving its way in defense and anti-explosion applications. A European consortium of nine partners have started developing an explosion containment system for aircraft. It aims at containing explosions in aircraft’s luggage area.
New fabric will continue to be developed world over and it would be interesting to see how it makes our world even stronger.