Air Force Research Lab to use silk in synthetic fibres
September 01, 2018 - United States Of America
Scientists at the Air Force Research Laboratory and Purdue University are trying to apply natural silk to synthetic fibres like artificial spider silk, which is stronger than the polymer Kevlar and more flexible than nylon. The aim is to develop a functional fibre that can be woven into sizeable, flexible fabrics using existing textile manufacturing methods.
For this, the team is studying the cooling and temperature regulation properties of natural silk.
Silk exhibits passive radiative cooling, meaning that it radiates more heat than it absorbs when in direct sunlight. On hot summer days, silk drops 10-15 degrees Fahrenheit when compared to reflective materials.
The cooling fabric is of tremendous potential benefit to the warfighter wearing body armour. Bulletproof vests and parachutes are two articles in line to be constructed with artificial spider silk. Current vests are burdensome due to the heavy weight and non-breathing material they are fabricated with. Parachutes constructed of the new material are stronger and able to carry larger payloads.
Estimates indicate that while artificial spider silk may initially cost twice as much as Kevlar, the product’s minimal weight, incredible strength and elasticity and potential adaptability for other needs are characteristics that enhance its salability.
“Making the warfighter more comfortable by enhancing body armour is just one of the many improvements my team hopes to make by studying natural silk,” said Dr. Augustine Urbas, researcher in the Functional Materials Division of the Materials and Manufacturing Directorate.
“Understanding natural silk will enable us to engineer multifunctional fibres with exponential possibilities. The ultra-strong fibres outperform the mechanical characteristics of many synthetic materials as well as steel. These materials could be the future in comfort and strength in body armour and parachute material for the warfighter.”
Tents for Forward Operating Bases could be composed of the natural material. This would enable the warfighter to work in a cooler environment.
Fibroin, a silk protein secreted by the silkworm, can be processed into a lightweight material for fabricating artificially engineered synthetic and optical materials.
The structured optical materials can reflect, absorb, concentrate or split light enabling a material to perform differently in a specific situation.
Understanding light transport and heat transfer will lead to various innovations. According to the AFRL researchers, learning from silk to assist with developing material synthesis and design processes in the future is a great opportunity. (SV)