Strep

EU-Projekt: STREP – Streamlined Textile Waste Streams For Recycling Optimization

Post-consumer textile waste has posed significant ecological and economic challenges for Europe for many years.
The heterogeneous composition of garments, complex material blends, and a wide variety of finishes significantly limit the feasibility of reliable sorting and high-quality recycling using current technologies. Yet these very steps are crucial to establishing a functioning circular economy.

STREP therefore aims to develop a novel, systemic solution that enables textile waste to be processed through the combined application of advanced sensor technologies, AI-driven sorting systems, and integrated mechanical and chemical recycling processes, ultimately allowing for fully closed material loops. A key ambition is to deliver high-quality recycled fibres and yarns—even from highly complex input materials—that can be reintegrated into new products. These solutions are fully aligned with the objectives of the European Green Deal, the EU Strategy for Sustainable and Circular Textiles, and the 2030 sustainability targets.

Within the project, Reutlingen University assumes two core responsibilities that are essential to ensuring textiles are designed for reusability and recyclability from the earliest stages of product development.

One key focus is the design and implementation of a material database characterised by high usability and a clearly structured, application-oriented logic. The database systematically documents fibres, yarns, fabrics, and finishing processes and evaluates them with regard to durability and recyclability.

The database will ultimately serve as a reference tool for industry stakeholders, enabling designers, product developers, and production managers to select materials at an early stage that meet both functional requirements and circularity principles. This represents a critical step towards making downstream recycling processes technically feasible and economically viable.

A second major focus is the development of a manufacturing guideline that provides manufacturers with concrete recommendations on joining techniques as well as the selection and integration of components. The objective is to design textile products in such a way that they can be easily disassembled and recycled at the end of their life cycle—without compromising durability during use.

To this end, a range of seam constructions in combination with different sewing yarns will be systematically analysed and mechanically tested for various application scenarios. In addition, alternative joining technologies such as ultrasonic welding and adhesive bonding will be evaluated using the same criteria. Based on these results, recommendations will be derived for optimal seam/yarn combinations or alternative joining techniques.

From a recycling perspective, it is also essential that components such as zippers and buttons can be removed prior to processing, as they may cause significant damage to recycling machinery. The project therefore investigates methods for attaching such components in a way that allows them to be easily identified and dismantled before recycling.

The combination of in-depth material expertise and practical, industry-ready manufacturing strategies forms a key foundation for enabling future generations of textile products to be more sustainable, resource-efficient, and at the same time economically competitive.