Composite materials bring numerous advantages, particularly in the automotive and aerospace sectors. They are much lighter than metals, but also stiffer, leading to lower energy consumption in vehicles and higher performance. Thus, composites are an important cog in reducing the carbon footprint. Unfortunately, apart from the high cost associated with composites, they are also notoriously difficult to recycle. So, once they reach the end of their lifetime, materials like carbon fiber end up in landfills.
However, that could change soon, as researchers at the University of South Carolina claim they developed a method to upcycle carbon fiber. This is huge news, as it would not only solve the apparent waste issue but could also lead to cheaper composite materials in the future. USC’s method can be used to upcycle panels from cars and light rail vehicles, where carbon fiber reinforced polymers (CFRPs) are increasingly used for efficiency and performance gains.
CFRPs contain thin fibers made from carbon atoms, which provide incredible tensile strength and stiffness, bound by a plastic-like material, usually epoxy, polyester, or vinyl resins. Currently, only 1% of these materials are partially recycled, with a method that includes burning the polymer to extract the fibers. This method won’t fully restore the material, but also isn’t sustainable.
USC’s solution to this problem is using fungi. Yup, fungi might be the solution to many of our problems – in 2011, researchers at Yale University found that the Pestalotiopsis fungus eats plastic, and can thrive in oxygen-starver environments.
For recycling carbon fiber, though, USC’s researchers utilized an engineered strain of Aspergillus nidulans that was first engineered in the Berl Oakley lab at the University of Kansas. The fungus feeds on benzoic acid, which is produced from a chemical fiber recycling reaction, and secrets a chemical called OTA ((2Z,4Z,6E)-octa-2,4,6-trienoic acid). This chemical can be used to make antibiotics and anti-inflammatory drugs, while the carbon fibers can be reused again in new composite materials. Two birds with one stone, right?
“This breakthrough comes at a crucial time, as the demand for CFRPs continues to grow,” said Travis Williams, professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences. “With projections indicating significant increases in CFRP waste in the coming decades, this concept offers a promising solution for sustainable materials management.”
Article Source: USC
Image Source: 222fjb at English Wikipedia, CC BY-SA 3.0, Link
