Regenerated Cotton for Electronic Textiles

Project Information

RETEX

Grant agreement ID: 101086305

DOI

10.3030/101086305

EC signature date 18 October 2022

Start date 1 January 2023

End date 31 December 2026

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 814 200,00

Coordinated by

ISTANBUL TEKNIK UNIVERSITESI
Türkiye

Periodic Reporting for period 1 - RETEX (Regenerated Cotton for Electronic Textiles)

Reporting period: 2023-01-01 to 2024-12-31

Summary of the context and overall objectives of the project

The RETEX project ("Regenerated Cotton for Electronic Textiles") responds to urgent environmental and industrial challenges at the intersection of textile sustainability, material circularity, and the rapidly expanding e-textile sector. The textile industry is one of the world's most resource-intensive and polluting sectors—generating over 92 million tons of waste and 715 million tons of CO2 emissions annually. Cotton, while being a natural and biodegradable fiber, demands an enormous amount of water and energy, making the need for regenerative and circular alternatives critically important.
Simultaneously, the rise of smart textiles and wearable electronics is creating a growing demand for flexible, breathable, and functional materials. However, the current smart textile market is heavily reliant on virgin synthetic materials and often overlooks sustainability. The integration of electrical functionality (e.g. conductivity, sensing) into recycled or renewable textile materials remains an unmet technical and market need.
RETEX aims to fill this gap by pioneering an eco-innovative approach to regenerate cotton from post-consumer textile waste and functionalize it with advanced conductive materials like silver nanowires and carbon nanotubes. The regenerated, conductive textile fibers developed in the project are designed to be scalable, washable, cost-effective, and suitable for multiple applications—ranging from wearable electronics and healthcare garments to sustainable fashion.

Project Pathway to Impact
The pathway to impact is structured through:

- Regenerating cotton via green chemistry and embedding conductivity without compromising biodegradability or performance.
- Developing electrospinning and wet spinning techniques for scale-up and optimization.
-Through consortium secondments, technology transfer, and participation in trade fairs (e.g. Techtextil), RETEX builds early-stage industry adoption and awareness.
-Training early-stage researchers across disciplines and sectors, laying a foundation for future innovation leadership in sustainable smart textiles.

Expected Scale and Significance of Impact
RETEX is expected to:

Reduce textile waste through high-value regeneration,

Lower environmental footprint of e-textiles,

Create new business opportunities at the nexus of circular economy and digital fashion,

Advance EU leadership in sustainable materials and wearable technologies.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

WP1 – Development of Regenerated Cellulosic Fibres from Cotton Waste
The main goal of WP1 was to develop regenerated cellulose fibres from cotton-based textile waste using sustainable methods. Two researchers from ITU and Wearonics were seconded to Freyzein (Austria) for 12 months, where they conducted lab-scale wet-spinning experiments based on Dr. Byrne’s method using a binary solvent system (DMSO and 1-butyl-3-methylimidazolium acetate).
Key Activities and Results:

Raw Material Preparation: White post-consumer cotton t-shirts were shredded, chemically pretreated with 10 wt.% NaOH at 90 °C, and dried to produce cellulose powder.

Spinning Solution Optimization:

Initial trials used 6 wt.% cotton in an 80:20 DMSO/IL solvent system.

Due to high viscosity, solution concentration was reduced to 3 wt.%, but still unsuitable for syringe-pump delivery.

Alternative Cellulose Source: Cellulose acetate fibres were used to develop electrospun fibres. Electrospinning trials optimized voltage and tip-to-collector distances.

Successful Nanofiber Production: A binary DMSO:EtOH solvent system enabled defect-free CA nanofibers at 10 wt.% concentration, confirmed via optical microscopy.

WP2 – Development of Conductive Textile Structures

WP2 aimed to integrate conductive materials (AgNWs and CNTs) into regenerated cellulosic substrates using plying (WP2a) and embedding (WP2b) techniques.

Key Activities and Results:

Initial Focus on AgNWs: Due to lab limitations, CNT usage was postponed. Silver nanowires were selected, validated through microscopy and electrical testing (0.9 ± 0.2 Ω).

Wet Spinning of AgNW-CA Composite Fibres:

AgNWs (1 mg/ml) were added to CA spinning solution.

Wet spinning setup was developed in-house; fibres showed variable conductivity (13.57 ± 4.0 Ω).

SEM/EDAX showed AgNWs primarily located on fibre surface (10.2 wt.% Ag).

Coating on Commercial Yarns:

AgNW coatings applied to cellulosic multifilament yarns.

Saturated yarns showed better conductivity (3.02 ± 1.63 Ω) than dry ones.

Coating lacked homogeneity and stability—further improvements (e.g. L-cysteine/citric acid) planned.

WP3.2 – Design and Development of E-Textile Prototypes
Although dependent on WP1 and WP2, WP3.2 activities commenced with secondments of Wearonics researchers to TU Dresden for 9 months each.

Key Activities and Results:

Preparatory Work:

Knowledge transfer and hands-on training in:

Silver nanowire synthesis (polyol method),

Spacer stitching,

Flexible interconnections,

Modelling textile structures.

Infrastructure Setup: Electrospinning equipment installation and basic functionality tests using PVP and CA solutions.

Capacity Building: Researchers developed practical and academic skills to be applied to regenerated conductive fibres in upcoming stages.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Results and Potential Impacts (Indicative)
The RETEX project has made notable progress toward its overarching goal of developing sustainable, regenerated cotton-based e-textiles. Key scientific and technological outcomes include:

Development of regenerated cellulose fibers using a green solvent system (DMSO and ionic liquid), reducing environmental impact compared to conventional viscose.

Integration of silver nanowires into wet-spun and coated textile fibers, achieving surface conductivities as low as ~3 Ω.

Electrospinning of nanofibrous webs from cellulose acetate with and without conductive additives.

Demonstration of functional yarns and textile prototypes with flexible electrical interconnects.

Key Needs for Further Uptake and Success
To translate the RETEX outcomes into commercial, industrial, and societal impact, the following areas are identified as critical enablers:

1. Further Research & Demonstration
Continued optimization of spinning processes, especially embedding CNTs within regenerated fibers.

Validation of mechanical durability, washability, and user safety in real-life e-textile scenarios.

Integration of additional sensors and energy-harvesting modules for full-scale prototypes.

2. Commercialisation Support
Development of business models and techno-economic analysis for market readiness.

Feasibility studies for transitioning from lab-scale to industrial-scale wet/electrospinning setups.

3. Access to Markets and Finance
Engagement with early adopters and investors in fashion-tech, healthcare, and sustainable consumer goods.

Participation in industrial fairs (e.g. Techtextil, SmartCity Expo) to improve market visibility.

4. IPR Strategy and Support
Consolidation of intellectual property around the regenerated conductive fiber technology.

5. Internationalisation
Expansion of the project’s global outreach through international research exchanges and industrial liaisons beyond the EU.

Partnerships with textile manufacturers in regions heavily affected by textile waste.