Recycling textile waste (successfully) is challenging; even though 95 percent of textiles are fully recyclable, 85 percent find their way to landfill, per New York’s Department of Environmental Conservation.
Recycling electronic waste is equally complex. And recycling electronics integrated into conventional textiles? It’s a logistical end-of-life nightmare. But a group of United Kingdom-based scientists may have found wearable tech’s sweet spot.
The research team, led by the University of Southampton and the University of the West of England (UWE) Bristol, alleges that wearable electronic textiles (e-textiles) can be “both sustainable and biodegradable.”
The new study, featuring input from the universities of Exeter, Cambridge, Leeds and Bath, tests a novel approach for what the team calls “smart, wearable, and eco-friendly electronic textiles” (SWEET). Its findings, published by the multidisciplinary materials science journal “Energy and Environmental Materials,” underscore SWEET’s potential for healthcare applications and environmental monitoring.
“E-textiles…offer promising solutions for unobtrusive, real-time health monitoring, enhancing healthcare efficiency. However, their adoption is limited by performance and sustainability challenges in materials, manufacturing and recycling,” the research article reads. “This study introduces a sustainable paradigm for the fabrication of fully inkjet-printed Smart, Wearable, and Eco-friendly Electronic Textiles (SWEET) with the first comprehensive assessments of biodegradability and life cycle assessment.”
Considering e-textiles are simply textiles embedded with electronics (like batteries and lights) used for fashion or function, performance is paramount, as is their durability and environmental benignity. It’s a heavy lift, considering such textiles (their metallic components, to be exact) have recycling requirements at odds with all things green. In fact, the existing waste electrical and electronic equipment (WEEE) take-back and recycling processes “cannot handle” this new kind of waste, per the paper.
Nazmul Karim, the study lead and professor at the University of Southampton’s Winchester School of Art, elaborated on the challenges posed by traditional (aka, not sweet) e-textiles.
“Integrating electrical components into conventional textiles complicates the recycling of the material because it often contains metals, such as silver, that don’t easily biodegrade,” Karim said in a statement. “Our potential eco-friendly approach for selecting sustainable materials and manufacturing overcomes this, enabling the fabric to decompose when it is disposed of.”
The study marks the first sustainable approach to fabricating next-generation SWEET for “continuous and concurrent monitoring of human vital signs,” including skin surface temperature and heart rate. SWEET’s trident design features three layers: a sensing layer to interface with various sensors, a mid-layer for sensor integration, and a base fabric layer.
Lenzing’s biodegradable and renewable Tencel material is used as the base layer, given the wood pulp fiber’s sustainability and softness. Eco-minded conductive components, like graphene and PEDOT:PSS polymer composites, are precision inkjet-printed onto the fabric.
This e-textile fabrication manufacturing method deposits the exact number of functional materials the textile needs—in turn, using much fewer resources than conventional screen printing. By depositing the water-based conductive inks directly (and precisely) onto the substrates, harsh solvents are rendered obsolete. In contrast, conductive pattern customization for specific functionalities—like temperature sensors and non-metallic electrodes for ECG—is added.
Figure 1
Energy & Environmental Materials published by John Wiley & Sons Australia, Ltd on behalf of Zhengzhou University.
“The SWEET consists of a multi-layer sensing platform and attaches to textile gloves for monitoring human subjects’ skin surface temperature and heart rate variability,” the paper reads. “We integrated these textile-based electrodes into a glove to demonstrate how the simultaneous use of wearable e-textiles on the human body can measure the skin surface temperature, ECG signal and heart rate.”
The team then tested the functionality of the SWEET electronic textiles.
Five volunteers wore the glove-like prototype, which was used to monitor the volunteers’ skin temperature and heart rate while resting and running. The results revealed that the electrodes can accurately capture ECG signals and provide reliable readings. These findings confirm that the platform can perform continuous, concurrent vital sign monitoring on par with the medical industry’s current standards.
Dr. Shaila Afroj, an associate professor of sustainable materials from the University of Exeter and a study co-author, stressed just how significant this performance is.
“Achieving reliable, industry-standard monitoring with eco-friendly materials is a significant milestone,” Afroj said. “It demonstrates that sustainability doesn’t have to come at the cost of functionality, especially in critical applications like healthcare.”
To assess SWEET’s sustainability, the team “performed a soil burial test” of the inkjet-printed electrodes.
Various samples were buried for either 1-4 months before being assessed for weight loss, tensile strength and microbial impact. After four months, the graphene inkjet-printed fabric had lost 48 percent of its weight and 98 percent of its tensile strength–indicating rapid decomposition. The soil microbial analysis revealed that natural materials—aka, the Tencel and graphene—promoted the presence of both bacteria and fungi in the soil.
Different layers of e-textile after four months of decomposition.
Marzia Dulal
“Our life cycle analysis shows that graphene-based e-textiles have a fraction of the environmental footprint compared to traditional electronics,” the study’s first author, Commonwealth PhD scholar Marzia Dulal from UWE Bristol, said. “This makes them a more responsible choice for industries looking to reduce their ecological impact.”
As pollution—from both textiles and tech as well as e-textiles—continues to grow, the study hopes to bring attention and resources to understanding how wearable tech can be greener.
“Amid rising pollution from landfill sites, our study helps to address a lack of research in the area of biodegradation of e-textiles,” Karim said. “These materials will become increasingly more important in our lives, particularly in the area of healthcare, so it’s really important we consider how to make them more eco-friendly, both in their manufacturing and disposal.”
Now, the researchers hope to design SWEET-made wearable garments to help the healthcare sector—specifically, for the early detection and prevention of heart-related diseases that over 600 million people, per the British Heart Foundation, suffer from globally.
The study’s results are particularly relevant for healthcare applications, where wearable monitoring systems are becoming increasingly important. The biodegradable nature of SWEET reduces concerns about disposal and environmental pollution, making it a more responsible choice for future development.
“Our fabricated e-textiles offer a sustainable alternative for continuous physiological monitoring, reducing the need for intrusive sensors and enhancing user comfort,” the research article reads. “The integration of our developed textile electrodes into clothing enables vital sign detection, supporting continuous monitoring from lab to life and promoting the advancement of smart clothing technologies with sustainable materials.”
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