Credit: iStockPhoto
SYDNEY: By incorporating wool into the weave structure of Kevlar, a synthetic textile used in body armour, researchers say they can develop a lighter, more cost-effective bullet-resistant vest.
The tight weave of wool improves the energy absorption efficiency of Kevlar, reducing the number of protective layers required to stop bullets, say inventors. It could provide defence and police forces with a more practical alternative to protect personnel.
"While a typical Kevlar vest is made of about 36 layers, our wool-Kevlar blend only needs to be in the region of 30 layers to achieve the same bullet-resistant effect," said Rajiv Padhye, the co-creator on the vest and a textile technologist at the Royal Melbourne Institute of Technology (RMIT) in Melbourne.
More effective when wet?
Although Kevlar still provides the base strength needed to stop bullets, the reduction in layers derived from adding wool could mean a more comfortable, lighter and more affordable material - and one that could perform better in wet conditions.
“When water is present in Kevlar, it acts as a lubricant, meaning when bullets come through at high speed, there is less friction to stop the blow,” said co-creator Sinnappoo Kanesalingam, also an RMIT textile researcher.
Adding wool increases the frictional forces as well as increasing water absorbption, "helping to maintain the intended function of the original fabric," says Kanesalingam.
The standard of protection
The RMIT researchers said the wool-Kevlar combination passed an internationally recognised standard against handgun force, making it acceptable for adoption by the armed forces.
"Police forces may not encounter the same levels of threat as soldiers and, as such, for police and security forces, the fabric can be scaled down to make it even more cost-effective," said Kanesalingam.
However, the Melbourne-based company responsible for the testing did not support claims that the addition of wool improves existing soft-armour Kevlar.
