Textination Newsline

Researchers have developed a method to make adaptive and eco-friendly sensors that can be directly and imperceptibly printed onto a wide range of biological surfaces, whether that’s a finger or a flower petal.

The method, developed by researchers from the University of Cambridge, takes its inspiration from spider silk, which can conform and stick to a range of surfaces. These ‘spider silks’ also incorporate bioelectronics, so that different sensing capabilities can be added to the ‘web’.

The fibres, at least 50 times smaller than a human hair, are so lightweight that the researchers printed them directly onto the fluffy seedhead of a dandelion without collapsing its structure. When printed on human skin, the fibre sensors conform to the skin and expose the sweat pores, so the wearer doesn’t detect their presence. Tests of the fibres printed onto a human finger suggest they could be used as continuous health monitors.

This low-waste and low-emission method for augmenting living structures could be used in a range of fields, from healthcare and virtual reality, to electronic textiles and environmental monitoring. The results are reported in the journal Nature Electronics.

Although human skin is remarkably sensitive, augmenting it with electronic sensors could fundamentally change how we interact with the world around us. For example, sensors printed directly onto the skin could be used for continuous health monitoring, for understanding skin sensations, or could improve the sensation of ‘reality’ in gaming or virtual reality application.

While wearable technologies with embedded sensors, such as smartwatches, are widely available, these devices can be uncomfortable, obtrusive and can inhibit the skin’s intrinsic sensations.

Last year, some of the same researchers showed that if the fibres used in smart textiles were coated with materials that can withstand stretching, they could be compatible with conventional weaving processes. Using this technique, they produced a 46-inch woven demonstrator display.

“If you want to accurately sense anything on a biological surface like skin or a leaf, the interface between the device and the surface is vital,” said Professor Yan Yan Shery Huang from Cambridge’s Department of Engineering, who led the research. “We also want bioelectronics that are completely imperceptible to the user, so they don’t in any way interfere with how the user interacts with the world, and we want them to be sustainable and low waste.”

There are multiple methods for making wearable sensors, but these all have drawbacks. Flexible electronics, for example, are normally printed on plastic films that don’t allow gas or moisture to pass through, so it would be like wrapping your skin in cling film. Other researchers have recently developed flexible electronics that are gas-permeable, like artificial skins, but these still interfere with normal sensation, and rely on energy- and waste-intensive manufacturing techniques.

3D printing is another potential route for bioelectronics since it is less wasteful than other production methods, but leads to thicker devices that can interfere with normal behaviour. Spinning electronic fibres results in devices that are imperceptible to the user, but don't have a high degree of sensitivity or sophistication, and they’re difficult to transfer onto the object in question.

Now, the Cambridge-led team has developed a new way of making high-performance bioelectronics that can be customised to a wide range of biological surfaces, from a fingertip to the fluffy seedhead of a dandelion, by printing them directly onto that surface. Their technique takes its inspiration in part from spiders, who create sophisticated and strong web structures adapted to their environment, using minimal material.

The researchers spun their bioelectronic ‘spider silk’ from PEDOT:PSS (a biocompatible conducting polymer), hyaluronic acid and polyethylene oxide. The high-performance fibres were produced from water-based solution at room temperature, which enabled the researchers to control the ‘spinnability’ of the fibres. The researchers then designed an orbital spinning approach to allow the fibres to morph to living surfaces, even down to microstructures such as fingerprints.

Tests of the bioelectronic fibres, on surfaces including human fingers and dandelion seedheads, showed that they provided high-quality sensor performance while being imperceptible to the host.

“Our spinning approach allows the bioelectronic fibres to follow the anatomy of different shapes, at both the micro and macro scale, without the need for any image recognition,” said Andy Wang, the first author of the paper. “It opens up a whole different angle in terms of how sustainable electronics and sensors can be made. It’s a much easier way to produce large area sensors.”

Most high-resolution sensors are made in an industrial cleanroom and require the use of toxic chemicals in a multi-step and energy-intensive fabrication process. The Cambridge-developed sensors can be made anywhere and use a tiny fraction of the energy that regular sensors require.

The bioelectronic fibres, which are repairable, can be simply washed away when they have reached the end of their useful lifetime, and generate less than a single milligram of waste: by comparison, a typical single load of laundry produces between 600 and 1500 milligrams of fibre waste.

“Using our simple fabrication technique, we can put sensors almost anywhere and repair them where and when they need it, without needing a big printing machine or a centralised manufacturing facility,” said Huang. “These sensors can be made on-demand, right where they’re needed, and produce minimal waste and emissions.”

The research was supported in part by the European Research Council, Wellcome, the Royal Society, and the Biotechnology and Biological Sciences Research Council (BBSRC), part of UK Research and Innovation (UKRI).

In collaboration with industrial partners, researchers at the Fraunhofer WKI have developed a vehicle underbody made from natural fibers and recycled plastics for automotive construction. The focus at the Fraunhofer WKI was directed at the development of the materials for injection molding as well as the hydrophobization of flax and hemp fibers for natural-fiber-reinforced mixed-fiber non-wovens.

The component fulfills the stringent technical requirements in the underbody area and could replace conventional lightweight vehicle underbodies in the future. With this development, the climate and environmental balance is optimized throughout the entire product life cycle.

The project partners Fraunhofer WKI, Thuringian Institute for Textile and Plastics Research (TITK), Röchling Automotive SE & Co. KG, BBP Kunststoffwerk Marbach Baier GmbH and Audi AG have succeeded in developing a sustainable overall concept for vehicle underbodies. The researchers have thereby taken a challenging component group with a high plastic content and made it accessible for the utilization of natural materials. Until now, natural-fiber-reinforced plastics have predominantly been used in cars for trim parts without significant mechanical functions. Structural components such as vehicle underbodies are, however, exposed to enormous loads and place high demands on the bending and crash behavior of the material. In modern lightweight vehicle concepts, high-performance materials made from glass-fiber-reinforced plastics are therefore utilized.

The project team was able to replace the glass fibers with natural materials such as flax, hemp and cellulose fibers and to produce underbody components with a natural-fiber content of up to 45%. In the area of polymers, virgin polypropylene was completely dispensed with and solely recyclates were utilized. All the challenges associated with this material changeover – both the lower initial mechanical properties of the materials and the temporally restricted processing windows – were solved by means of skillful compound combinations.

At the Fraunhofer WKI, materials for injection molding were developed. “Natural-fiber injection-molded compounds have so far been known primarily for their increased strength and stiffness compared to non-reinforced polymers. In the development of the vehicle underbody, we have furthermore succeeded in fulfilling the stringent requirements for low-temperature impact strength through an innovative combination of selected post-consumer recyclates (PCR) as a matrix and natural fibers of varying degrees of purity - without forfeiting the required stiffness and strength,” explained Moritz Micke-Camuz, Project Manager at the Fraunhofer WKI.

Within the framework of the development, fiber-composite components made from natural-fiber-reinforced mixed-fiber non-wovens (lightweight-reinforced thermoplastic, LWRT) were realized for the first time at the TITK and at Röchling. The developed product not only fulfills the mechanical requirements: It also withstands in particular the challenges posed by the humid environment in which it is used. For the hydrophobization of flax and hemp fibers for LWRT components, a continuous furfurylation process was developed at the Fraunhofer WKI. Through furfurylation, moisture absorption can be reduced by up to 35 percent without impairment of the bending strength of the subsequent components. The furfurylated fiber material can also be easily processed on a non-woven production line.

The prototype components produced were subsequently extensively tested both at component level and in road tests. Amongst others, the vehicles from the VW Group’s new “Premium Platform Electric” (PPE) were used for this purpose. Long-term experience has already been gathered within the framework of the series testing. The gratifying result of these tests: The newly developed biocomposites fulfill all standard requirements for underbody components and have proven to be suitable for series production. Neither the use of natural fibers nor of (post-consumer) recyclates leads to a significant impairment of the properties.

One major advantage of the innovation is the significantly improved carbon footprint: Compared to series production, 10.5 kilograms of virgin material (PP/glass fiber) can be replaced by 4.2 kilograms of natural fibers and 6.3 kilograms of post-consumer recyclate. As a result, CO2 emissions during production, use and product life have been reduced by up to 40 percent.

Within the scope of the development project, an innovative, holistic overall concept for vehicle underbodies, including recycling with cascading re-use of the components, was developed. From a technical point of view, vehicle underbodies can be manufactured entirely from the new, high-performance lightweight bio construction material in the future.

The project was funded by the German Federal Ministry for Economic Affairs and Climate Action (BMWK) via the project management organization TÜV Rheinland.

Tandem electrocatalytic-thermocatalytic conversion could help offset emissions of potent greenhouse gas by locking carbon away in a useful material.

Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Columbia University have developed a way to convert carbon dioxide (CO₂), a potent greenhouse gas, into carbon nanofibers, materials with a wide range of unique properties and many potential long-term uses. Their strategy uses tandem electrochemical and thermochemical reactions run at relatively low temperatures and ambient pressure. As the scientists describe in the journal Nature Catalysis, this approach could successfully lock carbon away in a useful solid form to offset or even achieve negative carbon emissions.

“You can put the carbon nanofibers into cement to strengthen the cement,” said Jingguang Chen, a professor of chemical engineering at Columbia with a joint appointment at Brookhaven Lab who led the research. “That would lock the carbon away in concrete for at least 50 years, potentially longer. By then, the world should be shifted to primarily renewable energy sources that don’t emit carbon.”

As a bonus, the process also produces hydrogen gas (H₂), a promising alternative fuel that, when used, creates zero emissions.

Capturing or converting carbon?
The idea of capturing CO₂ or converting it to other materials to combat climate change is not new. But simply storing CO₂ gas can lead to leaks. And many CO₂ conversions produce carbon-based chemicals or fuels that are used right away, which releases CO₂ right back into the atmosphere.

“The novelty of this work is that we are trying to convert CO₂ into something that is value-added but in a solid, useful form,” Chen said.

Such solid carbon materials—including carbon nanotubes and nanofibers with dimensions measuring billionths of a meter—have many appealing properties, including strength and thermal and electrical conductivity. But it’s no simple matter to extract carbon from carbon dioxide and get it to assemble into these fine-scale structures. One direct, heat-driven process requires temperatures in excess of 1,000 degrees Celsius.

“It’s very unrealistic for large-scale CO₂ mitigation,” Chen said. “In contrast, we found a process that can occur at about 400 degrees Celsius, which is a much more practical, industrially achievable temperature.”

The tandem two-step
The trick was to break the reaction into stages and to use two different types of catalysts—materials that make it easier for molecules to come together and react.

“If you decouple the reaction into several sub-reaction steps you can consider using different kinds of energy input and catalysts to make each part of the reaction work,” said Brookhaven Lab and Columbia research scientist Zhenhua Xie, lead author on the paper.

The scientists started by realizing that carbon monoxide (CO) is a much better starting material than CO₂ for making carbon nanofibers (CNF). Then they backtracked to find the most efficient way to generate CO from CO₂.

Earlier work from their group steered them to use a commercially available electrocatalyst made of palladium supported on carbon. Electrocatalysts drive chemical reactions using an electric current. In the presence of flowing electrons and protons, the catalyst splits both CO₂ and water (H₂O) into CO and H₂.

For the second step, the scientists turned to a heat-activated thermocatalyst made of an iron-cobalt alloy. It operates at temperatures around 400 degrees Celsius, significantly milder than a direct CO₂-to-CNF conversion would require. They also discovered that adding a bit of extra metallic cobalt greatly enhances the formation of the carbon nanofibers.

“By coupling electrocatalysis and thermocatalysis, we are using this tandem process to achieve things that cannot be achieved by either process alone,” Chen said.

Catalyst characterization
To discover the details of how these catalysts operate, the scientists conducted a wide range of experiments. These included computational modeling studies, physical and chemical characterization studies at Brookhaven Lab’s National Synchrotron Light Source II (NSLS-II)—using the Quick X-ray Absorption and Scattering (QAS) and Inner-Shell Spectroscopy (ISS) beamlines—and microscopic imaging at the Electron Microscopy facility at the Lab’s Center for Functional Nanomaterials (CFN).

On the modeling front, the scientists used “density functional theory” (DFT) calculations to analyze the atomic arrangements and other characteristics of the catalysts when interacting with the active chemical environment.

“We are looking at the structures to determine what are the stable phases of the catalyst under reaction conditions,” explained study co-author Ping Liu of Brookhaven’s Chemistry Division who led these calculations. “We are looking at active sites and how these sites are bonding with the reaction intermediates. By determining the barriers, or transition states, from one step to another, we learn exactly how the catalyst is functioning during the reaction.”

X-ray diffraction and x-ray absorption experiments at NSLS-II tracked how the catalysts change physically and chemically during the reactions. For example, synchrotron x-rays revealed how the presence of electric current transforms metallic palladium in the catalyst into palladium hydride, a metal that is key to producing both H₂ and CO in the first reaction stage.

For the second stage, “We wanted to know what’s the structure of the iron-cobalt system under reaction conditions and how to optimize the iron-cobalt catalyst,” Xie said. The x-ray experiments confirmed that both an alloy of iron and cobalt plus some extra metallic cobalt are present and needed to convert CO to carbon nanofibers.

“The two work together sequentially,” said Liu, whose DFT calculations helped explain the process.

“According to our study, the cobalt-iron sites in the alloy help to break the C-O bonds of carbon monoxide. That makes atomic carbon available to serve as the source for building carbon nanofibers. Then the extra cobalt is there to facilitate the formation of the C-C bonds that link up the carbon atoms,” she explained.

Recycle-ready, carbon-negative
“Transmission electron microscopy (TEM) analysis conducted at CFN revealed the morphologies, crystal structures, and elemental distributions within the carbon nanofibers both with and without catalysts,” said CFN scientist and study co-author Sooyeon Hwang.

The images show that, as the carbon nanofibers grow, the catalyst gets pushed up and away from the surface. That makes it easy to recycle the catalytic metal, Chen said.

“We use acid to leach the metal out without destroying the carbon nanofiber so we can concentrate the metals and recycle them to be used as a catalyst again,” he said.

This ease of catalyst recycling, commercial availability of the catalysts, and relatively mild reaction conditions for the second reaction all contribute to a favorable assessment of the energy and other costs associated with the process, the researchers said.

“For practical applications, both are really important—the CO₂ footprint analysis and the recyclability of the catalyst,” said Chen. “Our technical results and these other analyses show that this tandem strategy opens a door for decarbonizing CO₂ into valuable solid carbon products while producing renewable H₂.”

If these processes are driven by renewable energy, the results would be truly carbon-negative, opening new opportunities for CO₂ mitigation.

The low-cost FibeRobo, which is compatible with existing textile manufacturing techniques, could be used in adaptive performance wear or compression garments.

Researchers from MIT and Northeastern University developed a liquid crystal elastomer fiber that can change its shape in response to thermal stimuli. The fiber, which is fully compatible with existing textile manufacturing machinery, could be used to make morphing textiles, like a jacket that becomes more insulating to keep the wearer warm when temperatures drop.

Instead of needing a coat for each season, imagine having a jacket that would dynamically change shape so it becomes more insulating to keep you warm as the temperature drops.
A programmable, actuating fiber developed by an interdisciplinary team of MIT researchers could someday make this vision a reality. Known as FibeRobo, the fiber contracts in response to an increase in temperature, then self-reverses when the temperature decreases, without any embedded sensors or other hard components.

The low-cost fiber is fully compatible with textile manufacturing techniques, including weaving looms, embroidery, and industrial knitting machines, and can be produced continuously by the kilometer. This could enable designers to easily incorporate actuation and sensing capabilities into a wide range of fabrics for myriad applications.

The fibers can also be combined with conductive thread, which acts as a heating element when electric current runs through it. In this way, the fibers actuate using electricity, which offers a user digital control over a textile’s form. For instance, a fabric could change shape based on any piece of digital information, such as readings from a heart rate sensor.

“We use textiles for everything. We make planes with fiber-reinforced composites, we cover the International Space Station with a radiation-shielding fabric, we use them for personal expression and performance wear. So much of our environment is adaptive and responsive, but the one thing that needs to be the most adaptive and responsive — textiles — is completely inert,” says Jack Forman, a graduate student in the Tangible Media Group of the MIT Media Lab, with a secondary affiliation at the Center for Bits and Atoms, and lead author of a paper on the actuating fiber.

He is joined on the paper by 11 other researchers at MIT and Northeastern University, including his advisors, Professor Neil Gershenfeld, who leads the Center for Bits and Atoms, and Hiroshi Ishii, the Jerome B. Wiesner Professor of Media Arts and Sciences and director of the Tangible Media Group. The research will be presented at the ACM Symposium on User Interface Software and Technology.

Morphing materials
The MIT researchers wanted a fiber that could actuate silently and change its shape dramatically, while being compatible with common textile manufacturing procedures. To achieve this, they used a material known as liquid crystal elastomer (LCE).

A liquid crystal is a series of molecules that can flow like liquid, but when they’re allowed to settle, they stack into a periodic crystal arrangement. The researchers incorporate these crystal structures into an elastomer network, which is stretchy like a rubber band.

As the LCE material heats up, the crystal molecules fall out of alignment and pull the elastomer network together, causing the fiber to contract. When the heat is removed, the molecules return to their original alignment, and the material to its original length, Forman explains.

By carefully mixing chemicals to synthesize the LCE, the researchers can control the final properties of the fiber, such as its thickness or the temperature at which it actuates.

They perfected a preparation technique that creates LCE fiber which can actuate at skin-safe temperatures, making it suitable for wearable fabrics.

“There are a lot of knobs we can turn. It was a lot of work to come up with this process from scratch, but ultimately it gives us a lot of freedom for the resulting fiber,” he adds.
However, the researchers discovered that making fiber from LCE resin is a finicky process. Existing techniques often result in a fused mass that is impossible to unspool.

Researchers are also exploring other ways to make functional fibers, such as by incorporating hundreds of microscale digital chips into a polymer, utilizing an activated fluidic system, or including piezoelectric material that can convert sound vibrations into electrical signals.

Fiber fabrication
Forman built a machine using 3D-printed and laser-cut parts and basic electronics to overcome the fabrication challenges. He initially built the machine as part of the graduate-level course MAS.865 (Rapid-Prototyping of Rapid-Prototyping Machines: How to Make Something that Makes [almost] Anything).

To begin, the thick and viscous LCE resin is heated, and then slowly squeezed through a nozzle like that of a glue gun. As the resin comes out, it is cured carefully using UV lights that shine on both sides of the slowly extruding fiber.

If the light is too dim, the material will separate and drip out of the machine, but if it is too bright, clumps can form, which yields bumpy fibers.

Then the fiber is dipped in oil to give it a slippery coating and cured again, this time with UV lights turned up to full blast, creating a strong and smooth fiber. Finally, it is collected into a top spool and dipped in powder so it will slide easily into machines for textile manufacturing.
From chemical synthesis to finished spool, the process takes about a day and produces approximately a kilometer of ready-to-use fiber.

“At the end of the day, you don’t want a diva fiber. You want a fiber that, when you are working with it, falls into the ensemble of materials — one that you can work with just like any other fiber material, but then it has a lot of exciting new capabilities,” Forman says.

Creating such a fiber took a great deal of trial and error, as well as the collaboration of researchers with expertise in many disciplines, from chemistry to mechanical engineering to electronics to design.

The resulting fiber, called FibeRobo, can contract up to 40 percent without bending, actuate at skin-safe temperatures (the skin-safe version of the fiber contracts up to about 25 percent), and be produced with a low-cost setup for 20 cents per meter, which is about 60 times cheaper than commercially available shape-changing fibers.

The fiber can be incorporated into industrial sewing and knitting machines, as well as nonindustrial processes like hand looms or manual crocheting, without the need for any process modifications.
The MIT researchers used FibeRobo to demonstrate several applications, including an adaptive sports bra made by embroidery that tightens when the user begins exercising.

They also used an industrial knitting machine to create a compression jacket for Forman’s dog, whose name is Professor. The jacket would actuate and “hug” the dog based on a Bluetooth signal from Forman’s smartphone. Compression jackets are commonly used to alleviate the separation anxiety a dog can feel while its owner is away.

In the future, the researchers want to adjust the fiber’s chemical components so it can be recyclable or biodegradable. They also want to streamline the polymer synthesis process so users without wet lab expertise could make it on their own.

Forman is excited to see the FibeRobo applications other research groups identify as they build on these early results. In the long run, he hopes FibeRobo can become something a maker could buy in a craft store, just like a ball of yarn, and use to easily produce morphing fabrics.

“LCE fibers come to life when integrated into functional textiles. It is particularly fascinating to observe how the authors have explored creative textile designs using a variety of weaving and knitting patterns,” says Lining Yao, the Cooper-Siegel Associate Professor of Human Computer Interaction at Carnegie Mellon University, who was not involved with this work.

This research was supported, in part, by the William Asbjornsen Albert Memorial Fellowship, the Dr. Martin Luther King Jr. Visiting Professor Program, Toppan Printing Co., Honda Research, Chinese Scholarship Council, and Shima Seiki. The team included Ozgun Kilic Afsar, Sarah Nicita, Rosalie (Hsin-Ju) Lin, Liu Yang, Akshay Kothakonda, Zachary Gordon, and Cedric Honnet at MIT; and Megan Hofmann and Kristen Dorsey at Northeastern University.

During pregnancy, regular medical check-ups provide information about the health and development of the pregnant person and the child. However, these examinations only provide snapshots of their state, which can be dangerous, especially in high-risk cases. To enable convenient and continuous monitoring during this sensitive phase, an international research consortium is planning to further develop the technology of smart textiles. A patch equipped with highly sensitive electronics is meant to collect and evaluate vital data. In addition, the sensors will be integrated into baby clothing in order to improve the future of medical monitoring for newborns with the highest level of data security.

The beginning of a pregnancy is accompanied by a period of intensive health monitoring of the baby and the pregnant person. Conventional prenatal examinations with ultrasound devices, however, only capture snapshots of the respective condition and require frequent visits to doctors, especially in high-risk pregnancies. With the help of novel wearables and smart textiles, researchers in the EU-funded project Newlife aim to enable continuous obstetric monitoring in everyday life.

One goal of the consortium, consisting of 25 partners, is the development of a biocompatible, stretchable, and flexible patch to monitor the progress of the pregnancy and the embryo. Similar to a band-aid, the patch will be applied to the pregnant person’s skin, continuously recording vital data using miniaturized sensors (e.g., ultrasound) and transmitting it via Bluetooth.

For some time now, modern medical technology has been relying on smart textiles and intelligent wearables to offer patients convenient, continuous monitoring at home instead of stationary surveillance. At the Fraunhofer Institute for Reliability and Microelectronics IZM, a team led by Christine Kallmayer is bringing this technology to application-oriented implementation, benefitting from the Fraunhofer IZM’s years of experience with integrating technologies into flexible materials. For the integrated patch, the researchers are using thermoplastic polyurethane as base materials, in which electronics and sensors are embedded. This ensures that the wearing experience is similar to that of a regular band-aid instead of a rigid film.

To ensure that the obstetric monitoring is imperceptible and comfortable for both pregnant individuals and the unborn child, the project consortium plans to integrate innovative MEMS-based ultrasound sensors directly into the PU material. The miniaturized sensors are meant to record data through direct skin contact. Stretchable conductors made of TPU material tracks will then transmit the information to the electronic evaluation unit and finally to a wireless interface, allowing doctors and midwives to view all relevant data in an app. In addition to ultrasound, the researchers are planning to integrate additional sensors such as microphones, temperature sensors, and electrodes.

Even after birth, the new integration technology can be of great benefit to medical technology: With further demonstrators, the Newlife team plans to enable the monitoring of newborns. Sensors for continuous ECG, respiration monitoring, and infrared spectroscopy to observe brain activity will be integrated into the soft textile of a baby bodysuit and a cap. "Especially for premature infants and newborns with health risks, remote monitoring is a useful alternative to hospitalization and wired monitoring. For this purpose, we must guarantee an unprecedented level of comfort provided by the ultra-thin smart textiles: no electronics should be noticeable. Additionally, the entire module has to be extremely reliable, as the smart textiles should easily withstand washing cycles," explains Christine Kallmayer, project manager at Fraunhofer IZM.

For external monitoring of the baby's well-being, the project is also researching ways to use camera data and sensor technology in the baby's bed. Once the hardware basis of the patch, the textile electronics, and the sensor bed is built and tested, the project partners will take another step forward. Through cloud-based solutions, AI and machine learning will be used to simplify the implementation for medical staff and ensure the highest level of data security.

The Newlife project is coordinated by Philips Electronics Nederland B.V. and will run until the end of 2025. It is funded by the European Union under the Horizon Europe program as part of Key Digital Technologies Joint Undertaking under grant number 101095792 with a total of 18.7 million euros.

The technology developed by The Hong Kong Research Institute of Textiles and Apparel (HKRITA) with the support of H&M Foundation, can separate microplastics from wastewater using soundwaves. Acousweep is a plug-and-play application. The technology can be easily transported and connected to any wastewater facility. If the technology is implemented at an industrial scale, it will have a significant impact on the fashion industry’s sustainable footprint.
 
Microplastic pollution is a globally established problem and a threat to ecosystems, animals, and people. Microplastics come from a variety of sources, including from larger plastic debris that degrades into smaller and smaller pieces, or microbeads in exfoliating health and beauty products, or cleansers such as toothpaste. According to the European Environment Agency the major source of oceanic microplastic pollution, about 16%-35% globally, comes from synthetic textiles. Professor Christine Loh, Chief Development Strategist at the Institute for the Environment, The Hong Kong University of Science and Technology, agrees that this technology has great potential.

Microplastics typically refers to tiny plastic pieces or particles smaller than 5mm in diameter according to the definition of United Nations Environment Programme (UNEP) and the European Union (EU). The new technology can separate microplastic fibre longer than 20 μm, which is 250 times smaller than the typical size. Unlike existing filtration processes, the system enables continuous water treatment and easy collection of microplastic fibres by virtue of its acoustic manipulation technique.

Acousweep utilises sweeping acoustic waves in a specially shaped chamber to physically trap and separate microplastic fibres from wastewater effectively. The whole process is merely a physical collection and separation. No chemical, solvent or biological additives are needed. The separated microplastics drip into a collection tank for further treatment, such as recycling. Acousweep, with a developing lab-scale treatment system of the capacity of 100L of water per hour, can be upscaled in industrial plants. The system can be installed in a container with a processing capacity up to 5-10T per hour. The containerised system can be easily transported and connected to the existing sewage outlets of the wastewater treatment system.
 
Process of Microplastic Fibre Separation:

1. At one end of the chamber is a transducer that generates a sweeping acoustic wave at ultrasound frequencies. At the other end, there is a reflector, inside which sweeping acoustic waves are reflected and forms standing waves.
2. When standing waves are applied to the particles in a fluid, an acoustic radiation force traps the particles.
3. The standing waves then transfer the trapped particles to the reflector side; after that, particles concentrate at the apex of the reflector.
4. At the apex is a needle valve which is controlled by a sensory system that monitors the concentration of microplastic fibres there. When the concentration is sufficiently high, the sensory system opens the needle valve to let the microplastic fibres drip into a collection tank.
5. A high temperature can be applied to the collection tank to remove the water, leaving the fibres to agglomerate and form a large mass that can be easily dealt with in future treatment.

Green tech has just taken a leap forward in Hong Kong. Acousweep will help the garment and other industries to stop a highly damaging form of pollution. HKRITA used a new technique to remove the microplastics by using soundwave-based system, preventing them from getting into the sea and being ingested by sea life that can even be ingested by humans along the food chain. Acousweep has the capacity to revolutionize industry, says Professor Christine Loh, Chief Development Strategist at the Institute for the Environment, The Hong Kong University of Science and Technology.

 

Precisely applied metal-organic technology detects and captures toxic gases in air.

A durable copper-based coating developed by Dartmouth researchers can be precisely integrated into fabric to create responsive and reusable materials such as protective equipment, environmental sensors, and smart filters, according to a recent study.
 
The coating responds to the presence of toxic gases in the air by converting them into less toxic substances that become trapped in the fabric, the team reports in Journal of the American Chemical Society.

The findings hinge on a conductive metal-organic technology, or framework, developed in the laboratory of corresponding author Katherine Mirica, an associate professor of chemistry. First reported in JACS in 2017, the framework was a simple coating that could be layered onto cotton and polyester to create smart fabrics the researchers named SOFT—Self-Organized Framework on Textiles. Their paper demonstrated that SOFT smart fabrics could detect and capture toxic substances in the surrounding environment.

For the newest study, the researchers found that—instead of the simple coating reported in 2017—they can precisely embed the framework into fabrics using a copper precursor that allows them to create specific patterns and more effectively fill in the tiny gaps and holes between threads.

The researchers found that the framework technology effectively converted the toxin nitric oxide into nitrite and nitrate, and transformed the poisonous, flammable gas hydrogen sulfide into copper sulfide. They also report that the framework’s ability to capture and convert toxic materials withstood wear and tear, as well as standard washing.
 
The versatility and durability the new method provides would allow the framework to be applied for specific uses and in more precise locations, such as a sensor on protective clothing, or as a filter in a particular environment, Mirica said.

“This new method of deposition means that the electronic textiles could potentially interface with a broader range of systems because they’re so robust,” she said. “This technological advance paves the way for other applications of the framework’s combined filtration and sensing abilities that could be valuable in biomedical settings and environmental remediation.”
The technique also could eventually be a low-cost alternative to technologies that are cost prohibitive and limited in where they can be deployed by needing an energy source, or—such as catalytic converters in automobiles—rare metals, Mirica said.
 
“Here we’re relying on an Earth-abundant matter to detoxify toxic chemicals, and we’re doing it without any input of outside energy, so we don’t need high temperature or electric current to achieve that function,” Mirica said.

Co-first author Michael Ko, initially observed the new process in 2018 as he attempted to deposit the metal-organic framework onto thin-film copper-based electrodes, Mirica said. But the copper electrodes would be replaced by the framework.

“He wanted it on top of the electrodes, not to replace them,” Mirica said. “It took us four years to figure out what was happening and how it was beneficial. It’s a very straightforward process, but the chemistry behind it is not and it took us some time and additional involvement of students and collaborators to understand that.”

The team discovered that the metal-organic framework “grows” over copper, replacing it with a material with the ability to filter and convert toxic gases, Mirica said. Ko and co-author Lukasz Mendecki, a postdoctoral scholar in the Mirica Group from 2017-18, investigated methods for applying the framework material to fabric in specific designs and patterns.

Co-first author Aileen Eagleton, who is also in the Mirica Group, finalized the technique by optimizing the process for imprinting the metal-organic framework onto fabric, as well as identifying how its structure and properties are influenced by chemical exposure and reaction conditions.

Future work will focus on developing new multifunctional framework materials and scaling up the process of embedding the metal-organic coatings into fabric, Mirica said.

Producing infection control clothing requires a lot of energy and uses lots of material resources. Fraunhofer researchers have now developed a technology which helps to save materials and energy when producing nonwovens. A digital twin controls key manufacturing process parameters on the basis of mathematical modeling. As well as improving mask manufacturing, the ProQuIV solution can also be used to optimize the production parameters for other applications involving these versatile technical textiles, enabling manufacturers to respond flexibly to customer requests and changes in the market.

Nonwoven infection control masks were being used in their millions even before the COVID-19 pandemic and are regarded as simple mass-produced items. Nevertheless, the manufacturing process used to make them needs to meet strict requirements regarding precision and reliability. According to DIN (the German Institute for Standardization), the nonwoven in the mask must filter out at least 94 percent of the aerosols in the case of the FFP-2 mask and 99 percent in the case of the FFP-3 version. At the same time, the mask must let enough air through to ensure that the wearer can still breathe properly. Many manufacturers are looking for ways to optimize the manufacturing process. Furthermore, production needs to be made more flexible so that companies are able to process and deliver versatile nonwovens for a wide range of different applications and sectors.

ProQuIV, the solution developed by the Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslautern, fulfills both of these aims. The abbreviation “ProQuIV” stands for “Production and Quality Optimization of Nonwoven Infection Control Clothing” (Produktions- und Qualitätsoptimierung von Infektionsschutzkleidung aus Vliesstoffen). The basic idea is that manufacturing process parameters are characterized with regard to their impact on the uniformity of the nonwoven, and this impact is then linked to properties of the end product; for example, a protective mask. This model chain links all relevant parameters to an image analysis and creates a digital twin of the production process. The digital twin enables real-time monitoring and automatic control of nonwoven manufacturing and thus makes it possible to harness potential for optimization.

Dr. Ralf Kirsch, who works in the Flow and Material Simulation department and heads up the Filtration and Separation team, explains: “With ProQuIV, the manufacturers need less material overall, and they save energy. And the quality of the end product is guaranteed at all times.”

Nonwoven manufacturing with heat and air flow
Nonwovens for filtration applications are manufactured in what is known as the
meltblown process. This involves melting down plastics such as polypropylene and forcing them through nozzles so they come out in the form of threads referred to as filaments. The filaments are picked up on two sides by air flows which carry them forward almost at the speed of sound and swirl them around before depositing them on a collection belt. This makes the filaments even thinner: By the end of the process, their thickness is in the micrometer or even submicrometer range. They are then cooled, and binding agents are added in order to create the nonwoven. The more effectively the temperature, air speed and belt speed are coordinated with each other, the more uniform the distribution of the fibers at the end and therefore the more homogeneous the material will appear when examined under a transmitted light microscope. Lighter and darker areas can thereby be identified — this is referred to by experts as cloudiness. The Fraunhofer team has developed a method to measure a cloudiness index on the basis of image data. The light areas have a low fiber volume ratio, which means that they are less dense and have a lower filtration rate. Darker areas have a higher fiber volume and therefore a higher filtration rate. On the other hand, the higher air flow resistance in these areas means that they filter a smaller proportion of the air that is breathed in. A larger proportion of the air flows through the more open areas which have a less effective filtration effect.

Production process with real-time control
In the case of ProQuIV, the transmitted light images from the microscope are used to calibrate the models prior to use. The experts analyze the current condition of the textile sample and use this information to draw conclusions about how to optimize the system — for example, by increasing the temperature, reducing the belt speed or adjusting the strength of the air flows. “One of the key aims of our research project was to link central parameters such as filtration rate, flow resistance and cloudiness of a material with each other and to use this basis to generate a method which models all of the variables in the production process mathematically,” says Kirsch. The digital twin monitors and controls the ongoing production process in real time. If the system deviates slightly from where it should be — for example, if the temperature is too high — the settings are corrected automatically within seconds.

Fast and efficient manufacturing
“This means that it is not necessary to interrupt production, take material samples and readjust the machines. Once the models have been calibrated, the manufacturer can be confident that the nonwoven coming off the belt complies with the specifications and quality standards,” explains Kirsch. ProQuIV makes production much more efficient — there is less material waste, and the energy consumption is also reduced. Another advantage is that it allows manufacturers to develop new nonwoven-based products quickly — all they have to do is change the target specifications in the modeling and adjust the parameters. This enables production companies to respond flexibly to customer requests or market trends.

This might sound logical but can be quite complex when it comes to development. The way that the values for filtration performance and flow resistance increase, for example, is not linear at all, and they are not proportional to the fiber volume ratio either. This means that doubling the filament density does not result in double the filtration performance and flow resistance — the relationship between the parameters is much more complex than that. “This is precisely why the mathematical modeling is so important. It helps us to understand the complex relationship between the individual process parameters,” says ITWM researcher Kirsch. The researchers are able to draw on their extensive expertise in simulation and modeling for this work.

More applications are possible
The next step for the Fraunhofer team is to reduce the breathing resistance of the nonwovens for the wearer without impairing the protective effect. This is made possible by electrically charging the fibers and employing a principle similar to that of a feather duster. The electric charge causes the textile fabric to attract the tiniest of particles which could otherwise slip through the pores. For this purpose, the strength of the electrostatic charge is integrated into the modeling as a parameter.

The Fraunhofer researchers’ plans for the application of this method extend far beyond masks and air filters. Their technology is generally applicable to the production of nonwovens — for example, it can also be used in materials for the filtration of liquids. Furthermore, ProQuIV methods can be used to optimize the manufacture of nonwovens used in sound-insulating applications.

Patients with severe respiratory or lung diseases require intensive treatment and their lung function needs to be monitored on a continuous basis. As part of the Pneumo.Vest project, Fraunhofer researchers have developed a technology whereby noises in the lungs are recorded using a textile vest with integrated acoustic sensors. The signals are then converted and displayed visually using software. In this way, patients outside of intensive care units can still be monitored continuously. The technology increases the options for diagnosis and improves the patient’s quality of life.

For over 200 years, the stethoscope has been a standard tool for doctors and, as such, is a symbol of the medical profession. In television hospital dramas, doctors are seen rushing through the halls with a stethoscope around their neck. Experienced doctors do indeed use them to listen very accurately to heartbeats and the lungs and, as a result, to diagnose illnesses.

Now, the stethoscope is getting some help. As part of the Pneumo.Vest project, researchers of the Fraunhofer Institute for Ceramic Technologies and Systems IKTS at the Berlin office have developed a textile vest with integrated acoustic sensors, presenting a high-performance addition to the traditional stethoscope. Piezoceramic acoustic sensors have been incorporated into the front and back of the vest to register any noise produced by the lungs in the thorax, no matter how small. A software program records the signals and electronically amplifies them, while the lungs are depicted visually on a display. As the software knows the position of each individual sensor, it can attribute the data to its precise location. This produces a detailed acoustic and optical picture of the ventilation situation of all parts of the lungs. Here is what makes it so special: As the system collects and stores the data permanently, examinations can take place at any given time and in the absence of hospital staff. Pneumo.Vest also indicates the status of the lungs over a period of time, for example over the previous 24 hours. Needless to say, traditional auscultation can also be carried out directly on the patients. However, instead of carrying out auscultation manually at different points with a stethoscope, a number of sensors are used simultaneously.

“Pneumo.Vest is not looking to make the stethoscope redundant and does not replace the skills of experienced pneumologists. However, auscultation or even CT scans of the lungs only ever present a snapshot at the time of the examination. Our technology provides added value because it allows for the lungs to be monitored continuously in the same way as a long-term ECG, even if the patient is not attached to machines in the ICU but has instead been admitted to the general ward,” explains Ralf Schallert, project manager at Fraunhofer IKTS.

Machine learning algorithms aid with diagnosis
Alongside the acoustic sensors, the software is at the core of the vest. It is responsible for storing, depicting and analyzing the data. It can be used by the doctor to view the acoustic events in specific individual areas of the lungs on the display. The use of algorithms in digital signal processing enables a targeted evaluation of acoustic signals. This means it is possible, for example, to filter out heartbeats or to amplify characteristic frequency ranges, making lung sounds, such as rustling or wheezing, much easier to hear.

On top of this, the researchers at Fraunhofer IKTS are developing machine learning algorithms. In the future, these will be able to structure and classify complex ambient noises in the thorax. Then, the pneumologist will carry out the final assessment and diagnosis.

Discharge from the ICU
Patients can also benefit from the digital sensor alternative. When wearing the vest, they can recover without requiring constant observation from medical staff. They can transfer to the general ward and possibly even be sent home and move about more or less freely. Despite this, the lungs are monitored continuously, and any sudden deterioration can be reported to medical personnel straight away.

The first tests with staff at the University Clinic for Anesthesiology and Intensive Therapy at the University of Magdeburg have shown that the concept is successful in practice. “The feedback from doctors was overwhelmingly positive. The combination of acoustic sensors, visualization and machine learning algorithms will be able to reliably distinguish a range of different lung sounds,” explains Schallert. Dr. Alexander Uhrig from Charité – Universitätsmedizin Berlin is also pleased with the technology. The specialist in infectiology and pneumology at the renowned Charité hospital was one of those who initiated the idea: “Pneumo.Vest addresses exactly what we need. It serves as an instrument that expands our diagnostic options, relieves the burden on our hospital staff and makes hospital stays more pleasant for patients.”

The technology was initially designed for respiratory patients, but it also works well for people in care facilities and for use in sleep laboratories. It can also be used to train young doctors in auscultation.

Increased need for clinical-grade wearables
With Pneumo.Vest, the researchers at Fraunhofer IKTS have developed a product that is cut out for the increasingly strained situation at hospitals. In Germany, 385,000 patients with respiratory or lung diseases require inpatient treatment every year. Over 60 percent are connected to a ventilator for more than 24 hours. This figure does not account for the current increase in respiratory patients due to the COVID-19 pandemic. As a result of increasing life expectancy, the medical industry also expects the number of older patients with breathing problems to increase. With the help of technology from Fraunhofer IKTS, the burden on hospitals and, in particular, costly ICUs can be relieved as their beds will no longer be occupied for quite as long.

It should be added that the market for such clinical-grade wearables is growing rapidly. These are compact medical devices that can be worn directly on the body to measure vital signs such as heartbeat, blood oxygen saturation, respiratory rate or skin temperature. As a medical device that can be used flexibly, Pneumo.Vest fits in perfectly with this development. But do not worry: Doctors will still be using the beloved stethoscope in the future.

Fraunhofer “M³ Infekt” cluster project
Pneumo.Vest is just one part of the extensive M³ Infekt cluster project. Its objective is to develop monitoring systems for the decentralized monitoring of patients. The current basis of the project is the treatment of COVID-19 patients. With the SARS-CoV2 virus, it is common for even mild cases to suddenly deteriorate significantly. By continuously monitoring vital signs, any deterioration in condition can be quickly identified and prompt measures for treatment can be taken.

M3 Infekt can also be used for a number of other symptoms and scenarios. The systems have been designed to be modular and multimodal so that biosignals such as heart rate, ECG, oxygen saturation, or respiratory rate and volume can be measured, depending on the patient and illness.

A total of ten Fraunhofer institutes are working on the cluster project under the leadership of the Fraunhofer Institute for Integrated Circuits IIS in Dresden. Klinikum Magdeburg, Charité – Universitätsmedizin Berlin and the University Hospitals of Erlangen and Dresden are involved as clinical partners.

Most people want to live as independently as possible in old age. Exhibitors at the industry's leading trade fair ALTENPFLEGE from April 26 to 28 in Essen, Germany will be showing how senior facilities with modern interior design and smart equipment meet this need.

Demand for forms of housing such as service living is on the rise. Studies predict a need for around 540,000 new service living units in the coming years. One of the major trends at this year's 32nd edition of the Altenpflege trade fair is how senior facilities are meeting the rapidly growing demand with flexible room design and digital support. They can be seen in the Aveneo special show, including intelligent systems for stove shut-off, lighting control and room temperature, as well as for fall sensors and emergency calls.

Future tenants or buyers of serviced apartments are prepared to invest specifically in their own living environment (source: Terragon study 2021). The focus is on a feel-good atmosphere, a high level of security and the option of using care services if required. "This can be facilitated by a cleverly thought-out arrangement of the rooms within a serviced apartment, for example by arranging the bathroom and bedroom right next to each other and making the wall with the washbasin rotatable," explains Carolin Pauly, managing director of Universal Rooms, which considers itself to be the interface between the wishes of the operators and the products in the serviced apartment market. "The furniture and furnishings industry is called upon to design modern collections with hidden product features that make life easier in old age," Pauly demands. This could be, for example, a grab handle built into the washbasin or a dining table that can be accessed by a wheelchair.

Lighting management also plays an important role. It should convey a sense of well-being and security as well as provide orientation and safety. Age-related clinical pictures in particular place high demands on lighting. Here, lighting systems that simulate the natural day and night rhythm can provide help.

Living, care and digitalization combined
The Chief Executive Officer of the Evangelische Heimstiftung (EHS - Evangelical Home Foundation), Bernhard Schneider, sees "an individually and comfortably furnished apartment that uses intelligent technology to provide a great deal of security and self-determination" as the senior living of the future. "I am certain: In the future, in a sector-free setting, we will have to understand housing, nursing and care, and digitalization even more strongly as building blocks that can be combined as needed."

According to Schneider, this starts with housing: In a nursing apartment or an assisted living apartment, in a shared apartment or other form of communal living, in a residence or an intergenerational project. All forms of housing should be well integrated into the neighborhood - this requires reliable, financed advisory structures, for example through neighborhood managers. In addition, there is care, support and assistance, in the form of day or night care, a mobile service or volunteers. "And technology, for example through our Aladien system, i.e. with intelligent home emergency call, fall sensors, stove shut-off, roller shutters and light control, video door telephony, etc. In the future, Aladien will evolve into a service robot," predicts Schneider.

This makes it possible for people to live a self-determined life and participate in society, even in old age. That's what people want, he says: a pleasant living environment, social contacts, cultural offerings and the certainty that someone will take care of them if necessary. "What we need for this is political commitment in the form of an ambitious funding program for modern forms of housing in old age," demands the EHS CEO. This would not only help the older generation, but young families could also benefit because this would free up the far too spacious apartments and terraced houses of the older generation for them.

ALTENPFLEGE – Trade fair and congress for the care industry since 1990
The traditional leading trade show for the care industry has so far been held alternately in Hanover and Nuremberg. From this year it alternates between Essen and Nuremberg. It covers all segments of professional geriatric care: services and products for care and therapy, occupation and education, IT and management, nutrition and home economics, textiles and hygiene as well as space and technology. In more than 30 lecture blocks, the accompanying trade congress covers the current topics of the industry, such as digitalization, the future of professional nursing care, hospice and palliative care, training or the new collectively agreed payment under the Healthcare Development Act (Gesundheitsversorgungsweiterentwicklungsgesetz - GVWG).