#Research & Development

2024-06-13

Synthetic leather made from recyclable and bio-based PBS

Pure PBS artificial leather. Photo: DITF 2024

A new type of pure synthetic leather meets the high requirements of the European Ecodesign Regulation. Made from a bio-based plastic, it is biodegradable and meets the requirements for a closed recycling process.

Many synthetic leathers consist of a textile substrate to which a polymer layer is applied. The polymer layer usually consists of an adhesive layer and a top layer, which is usually embossed. The textile backing and the top coat are usually completely different materials. Woven, knitted, or nonwoven fabrics made of PET, PET/cotton, or polyamide are often used as textile substrates. PVC and various polyurethanes are commonly used for coatings. The use of these established composite materials does not meet today's sustainability criteria. Recycling them by type is very costly or even impossible. They are not biodegradable. The search for alternative materials for the production of artificial leather is therefore urgent. In 2022, the EU adopted the Sustainable Products Initiative (SPI) ("Green Deal"). It includes an eco-design regulation that considers a product's life cycle in the conservation of resources. For textile and product design, this means incorporating closing the loop or end-of-life into product development.

In an AiF project carried out in close cooperation between the DITF and the Freiberg Institute gGmbH (FILK), it has now been possible to develop a synthetic leather in which both the fiber material and the coating polymer are identical. The varietal purity is a prerequisite for an industrial recycling concept.

The aliphatic polyester polybutylene succinate (PBS) was recommended as the base material because of its properties. PBS can be produced from biogenic sources and is now available on the market in several grades and in large quantities. Its biodegradability has been demonstrated in tests. The material can be processed thermoplastically. This applies to both the fiber material and the coating. Subsequent product recycling is facilitated by the thermoplastic properties.

In order to realize a successful primary spinning process and to obtain PBS filaments with good textile mechanical properties, process adjustments had to be made in the cooling shaft at the DITF. In the end, it was possible to spin POY yarns at relatively high speeds of up to 3,000 m/min, which had a tenacity of just under 30 cN/tex when stretched. The yarns could be easily processed into pure PBS fabrics. These in turn were used at FILK as a textile base substrate for the subsequent extrusion coating, where PBS was also used as a thermoplastic.

With optimized production steps, PBS composite materials with the typical structure of artificial leather could be produced. Purity and biodegradability fulfill the requirements for a closed recycling process.

Stylish design made from sustainable materials – two DITF research projects receive Techtextil Innovation Awards

Materials made from domestic, renewable raw materials reduce CO₂ emissions, prevent microplastics from entering the environment, and close the material cycle. The German Institutes for Textile and Fiber Research Denkendorf (DITF) are developing nature-based alternatives to synthetically produced and predominantly petroleum-based materials. Two research projects have received a prestigious Techtextil Innovation Award. NUO Flexholz and the lignin-coated material FormLig demonstrate that sustainable concepts can meet high standards of functionality and design. Both projects were carried out in close collaboration with industry.

Fabolose: Fabricating vegan and circular leather alternatives from bio-tech-derived cellulose

Fabulose is an EU funded project coordinated by the German Institutes of Textile and Fiber Research (DITF). Its consortium consists of leading research institutes, biotech innovators, and industry stakeholders who aim to create high-performance, biobased and recyclable leather-like fabrics, using efficient biotech production routes for bacterial cellulose, cyanophycin and bacterial pigments

More safety and comfort for protective clothing thanks to auxetic fabrics

When everyday materials are pulled, they stretch or elongate in the direction of the pull and become narrower in cross-section. We can also observe this property in two-dimensional textiles. Auxetic structures behave differently here. They have the striking property of not changing under tensile stress or even increasing their width or thickness. These properties are advantageous, for example, in protective textiles or textile filter media. The DITF are researching auxetic fabrics for various applications.

Walter Reiners Foundation Prize awarded to three ITA graduates

Sabina Dann, Lukas Balon and Annegret Storm from the Institut für Textiltechnik (ITA) of RWTH Aachen University were awarded the Walter Reiners Foundation Prize by the German Engineering Federation (VDMA) for their master’s and bachelor’s theses. Peter Dornier, Chairman of the Walter Reiners Foundation, presented the awards during Techtextil at the VDMA stand in Frankfurt am Main, Germany.

Young talents honoured – 60 years Walter Reiners Foundation

At the Techtextil trade fair in Frankfurt at the end of April, Peter D. Dornier, chairman of the VDMA’s Walter Reiners Foundation, presented awards to five successful young engineers. Promotion and sustainability awards were presented in the categories of bachelor’s/project theses and diploma/master’s theses. Academic theses are eligible for the sustainability awards if, for example, they develop solutions for resource-efficient products and technologies.

Regional hemp bast for lightweight construction profiles

The cultivation of fibre hemp for the production of ropes and clothing has a long tradition in Saxony. Due to its excellent fibre properties, it is also suitable as a renewable raw material for reinforcement in fibre composites. At the STFI and IWU in Chemnitz, the CannaPul project is cur- rently investigating how a regional value chain for hemp-based lightweight construction profiles can be established. To this end, the technical processing of hemp fibres into continuous fibre strands and their embedding in a suitable bio-based matrix are being investigated.

Barmag and Neumag showcase innovations across all manmade fiber processes

For the first time, Barmag is presenting itself alongside its new parent company, Rieter: At this year’s ITM in Istanbul, both companies will be represented from June 9 to 13 at the Tüyap Fair Convention and Congress Center in Hall 7, Booth 702B. As a technology leader in the field of chemical fiber equipment, Barmag will showcase its entire portfolio of systems for filament yarn, staple fiber, and nonwoven production, as well as solutions for the networked factory.