Covestro develops elastic fibers through CO2

Polymer materials manufacturer Covestro has developed a method of yielding elastic textile fibres through the partial use of carbon dioxide as a replacement to crude oils.

Produced in partnership with the Institute of Textile Technology at RWTH Aachen University, along with other collaborators, the fibres – made from CO2-based thermoplastic polyurethane (TPU) – were created through the utilisation of a melt spinning technique that, unlike conventional dry spinning, is not reliant on harmful solvents.

As such: “The CO2-based material could be a sustainable alternative to conventional elastic fibres in the near future,” Professor Thomas Gries, director of the Institute of Textile Technology at RWTH Aachen University has said. “[With Covestro] we can jointly drive the establishment of a new raw materials base for the textiles industry.”

The fibre innovation is subject to scaling as its creators see a gap in the market for brands and manufacturers keen to integrate materials that comply with circular business practices. The CO2-based elastic’s sustainability credentials are rooted in the fact it replaces crude oil with carbon dioxide as a raw material, and as such mitigates the effects of harmful solvents in product manufacture to provide an alternative that retains a high performance, with reportedly impressive stretch and tear-proof properties, but with a smaller CO2 footprint comparative to traditional elastic fibres.

The material is manufactured using a melt spinning technique in which the TPU is melted and pressed into fine threads before being processed into yarn. This, unlike dry spinning, does not require the use of solvents during processing, instead enabling carbon dioxide – with a cardyon precursor that’s already used in mattress and flooring manufacture – to be adopted.

“That’s a further, highly promising approach to enable ever broader use of carbon dioxide as an alternative raw material in the chemical industry and expand the raw materials base,” said Dr. Markus Steilemann, CEO of Covestro. “Our goal is to use CO2 in more and more applications in a circular economy process and save crude oil.”

Given its progress, further efforts to scale Covestro’s elastic fibre via the CO2Tex project will be funded by the German Federal Ministry of Education and Research (BMBF) which is keen to see the fibre enter the market. CO2Tex is part of BioTex Future, a project initiative of RWTH Aachen University which aspires to develop production and processing technologies that accelerate the launch of textile systems from bio-based polymeric materials.

Companies from the textile and medical engineering sectors are said to have tested the CO2-based fibres in socks, compression tubes and tapes. While the results of this testing have not been shared, perhaps Germany’s collective drive to get this sustainable solution to market is indicative of its performance and commercial feasibility.

Courtesy: EcoTextile News