<section id="isPasted">Imagine taking the radio frequency properties of the dish antennas you see on rooftops and knitting them into a wearable garment -- a sweater or a blanket that is ultralight, portable, easy to fold up and stow away. Not having to use heavy, bulky satellite antennas would make communications much easier for those who live or travel in remote locations -- a lightweight, flexible antenna that can send information over long distances would be a useful tool for both the public and private sectors.A <a href="http://engineering.columbia.edu/">Columbia Engineering</a> team reports that they have used their expertise in metasurfaces -- ultra-thin optical components that can control the propagation of light -- and a low-cost, highly scalable flat-knitting platform to create radio-frequency (RF) communications antennas that are easy to carry and deploy. The <a href="https://doi.org/10.1002/adma.202312087">study,&nbsp;</a>led by <a href="https://www.engineering.columbia.edu/faculty/nanfang-yu">Nanfang Yu</a>, associate professor of <a href="https://www.apam.columbia.edu/">applied physics and applied mathematics</a>, was published in Advanced Materials.</section><section><h2>Portable Knitted Antennas</h2><iframe width="640" height="360" src="https://www.youtube.com/embed/AIb2evFmk3U?&amp;wmode=opaque&amp;rel=0&amp;enablejsapi=1&amp;origin=https://www.wevolver.com" frameborder="0" allowfullscreen="" class="fr-draggable" data-lf-form-tracking-inspected-kn9eq4roawkarlvp="true" data-lf-yt-playback-inspected-kn9eq4roawkarlvp="true" data-lf-vimeo-playback-inspected-kn9eq4roawkarlvp="true"></iframe><h2 id="isPasted">Why knitting?</h2>Most RF antennas, particularly highly directional array antennas like reflectarrays are planar, rigid devices. While these devices will likely always remain state-of-the-art in terms of pure performance metrics, they are often large, heavy, and unwieldy and can be expensive to manufacture. Researchers have been investigating ways to produce smaller, more flexible antennas, including inkjet printing or screen-printing directly on textiles, and embroidery. But these techniques are quasi-additive approaches in which a conductive material is added to an existing textile instead of being integrated into the textile during the fabrication process of the textile itself, introducing problems such as delamination, slip, or cracking of the metallic region, as well as issues of production scalability.&nbsp;Yu’s group realized that what they needed to create was a high-throughput, inexpensive technique that directly integrates flat array antennas onto textiles. So they decided to study knitting and weaving, which, while being the most common approaches for fabricating patterned textiles, have not been explored as a way to produce complex array antennas with engineered electromagnetic responses.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1733275199005-news-nanfang-yu-knitted-meta-surface-1125x633.jpg" style="width: 100%px;" class="fr-fic fr-dib">Prof. Yu with the metalens prototype, which shapes a divergent wavefront into a planar one, increasing the directionality of the outgoing radio-frequency electromagnetic wave.<h2 id="isPasted">A Fair Isle approach</h2>The researchers took a novel approach to fabricating flexible, lightweight centimeter-wavelength metasurfaces. They leveraged an old-school colorwork knitting technique called float-jacquard knitting (think Fair Isle sweaters) and used commercially available metallic and dielectric yarns with existing knitting machinery to produce two prototype reflectarray devices, a metasurface lens (metalens) and a vortex-beam generating device. In the float-jacquard knitting technique, two or more types of yarn are used to produce a pattern: a yarn is floated loose beneath the fabric when not used and transferred back to the frontside as needed to create the desired pattern.By integrating the textile fabrication and antenna patterning into a single process, the team streamlined the fabrication process and alleviated common defects in fabric-based antennas. The group is the first to adapt flat-knitting techniques to incorporate antennas directly during the fabric production procedure – integrated fabrication – and able to do it at low cost and high yield on an industrial scale. For example, each of the prototype metasurfaces with a footprint of approximately one square meter was knit within 45 minutes. In addition, the flat-knit fabric devices withstood repeated washing and stretching on a frame.“The float-jacquard knitting technique used for making our textile metasurfaces is exactly the same technique that my mother used to make sweaters for me. I still remember a purple sweater I wore as a kid that had a row of white cats across the chest; I remember that when I inspected the inner side of the sweater, I saw white parallel yarns – the floats,” said Yu, a pioneer in researching nanophotonic devices like metasurfaces.&nbsp;He noted that these complex RF antennas can be readily produced by existing infrastructure: “We can leverage the very old and very well-established knitting industry to fulfill some of the needs of modern telecommunications. The facile and scalable nature of the fabrication approach means these devices could be inexpensive, ultra-lightweight, flexible variants of sophisticated radio-frequency communications antennas.”<h2>The results&nbsp;</h2>The researchers showed experimentally that when the metalens operates as a receiving antenna, it focuses an incident centimeter-wave into a tight (diffraction-limited) focal spot, and that when it operates as a transmitting antenna, it converts the divergent emission from a horn antenna (a common RF source) into a wave with planar wavefront – a highly directional beam.&nbsp;They also demonstrated that more complex wavefront shaping tasks can be accomplished: the vortex-beam generating metasurface produces a vortex beam – a beam with a corkscrew-shaped wavefront. Because of the peculiar wavefront, the vortex beam can carry an independent channel of information, thus a vortex beam and a beam with planar wavefront used together can make a communications channel twice as efficient.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1733275240960-yu-02.png" style="width: 100%px;" class="fr-fic fr-dib">A test swatch showing a wide variety of antenna archetypes, all knit using the float-jacquard knitting technique.<h2 id="isPasted">Next steps</h2>In future efforts, the researchers will explore modern knitting techniques – there are at least a dozen varieties – and knitting machines to realize more complex multi-functional designs – fabrics with combined designer electromagnetic, electronic, and mechanical responses. This could be used to engineer hinge points or folds, and electronic circuits into a fabric, which could be actuated to further facilitate stowage and deployment or even switch between different electromagnetic functionalities.The scalability of flat knitting ranks highly among all techniques used to produce flexible or rigid RF metasurfaces and reflectarrays: commercial flat-knitting machines are capable of producing textiles up to two meters in width and with no limitation in the length direction. The researchers will explore this advantage to create high-gain antennas with apertures several meters in diameter yet lightweight and stowable to be carried by satellites to communicate across vast distances.&nbsp;“It’s important to stress that these devices were fabricated using commercially available off-the-shelf yarns and leveraging established fabrication techniques,” Yu said. “I am almost certain that communities of knitters can come up with ingenious ways to integrate aesthetics and functionality into a sweater – a sweater that can double as a WiFi signal booster.”<hr><h2 id="isPasted">About the Study</h2>Journal: Advanced MaterialsTitle:&nbsp;<a href="https://doi.org/10.1002/adma.202312087">Flat-Knit, Flexible, Textile Metasurfaces</a>Authors: Michael J. Carter1,2, Leah Resneck3, Younes Ra'di4,5, Nanfang Yu1<ol><li>Department of Applied Physics and Applied Mathematics, Columbia Engineering</li><li>Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB&nbsp;</li><li>Zeis Textiles Extension, Wilson College of Textiles, North Carolina State University</li><li>Advanced Science Research Center, City University of New York</li><li>Department of Electrical Engineering and Computer Science, Syracuse University</li></ol>Funding: The study was supported by the Science, Mathematics, and Research for Transformation (SMART) Scholarship of the US Department of Defense award to Michael Carter, and National Science Foundation grant (ECCS-2004685), awarded to Nanfang Yu. Measurements were carried out in mm-Wave Characterization Lab at the Advanced Science Research Center, the City University of New York. Devices were fabricated in the Knitting Lab (part of the Zeis Textiles Extension) at the Wilson College of Textiles, North Carolina State UniversityThe authors have filed a provisional application for a patent with Columbia Technology Ventures based on the work reported in this article.</section>

Researchers are the first to use traditional flat-knitting techniques to fabricate flexible, lightweight metasurfaces--large-aperture antennas--that can easily be stowed and deployed for long-range communications

Columbia Engineers Knit a "Blanket" of Sophisticated Radio-Frequency Antennas

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Two new kinds of on-skin electronics allow users to build and customize them directly on the body – with potential applications in biometric sensing, medical monitoring, interactive prosthetic makeup and more.<a href="https://www.hybridbody.human.cornell.edu/#/skinlink/">SkinLink</a>, developed by the&nbsp;<a href="https://www.hybridbody.human.cornell.edu/">Hybrid Body Lab</a> led by&nbsp;<a href="https://www.human.cornell.edu/people/hk932">Cindy Hsin-Liu Kao</a>, assistant professor of human centered design in the College of Human Ecology, is an on-skin electronic interface that can be fabricated right on the body, providing flexibility in design depending on the intended use. And&nbsp;<a href="https://www.hybridbody.human.cornell.edu/#/ecskin/">ECSkin</a> is an electrochromic display interface that also can be fabricated in situ, and features modular design through tiles that can be arranged as desired.Some of the potential applications for SkinLink include vital-sign and posture monitoring, proximity sensing and body art.“Both of these projects are modular prototyping toolkits, to enable much more intricate on-skin circuitry prototyping,” Kao said. “And users are able to build the circuitry directly on the skin surface.”Doctoral student and lab member Pin-Sung Ku is lead author of “<a href="https://dl.acm.org/doi/10.1145/3596241">SkinLink:&nbsp;On-body Construction and Prototyping of Reconfigurable Epidermal Interfaces</a>,” which was presented in early October at UbiComp/ISWC ’24, the Association for Computing Machinery’s international joint conference on pervasive and ubiquitous computing.The work earned a Distinguished Paper Award from the journal, Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, where it was originally published in June 2023.<a href="https://dl.acm.org/doi/10.1145/3659613">ECSkin: Tessellating Electrochromic Films for Reconfigurable On-skin Displays</a>, which published May 15, 2024, in the same journal and for which Ku is also lead author, was also presented at the conference. Kao is senior author for both papers.SkinLink represents a step forward from&nbsp;<a href="https://news.cornell.edu/stories/2022/11/skinkit-offers-versatile-wearable-skin-computing">SkinKit, which the lab developed</a> and presented at UbiComp in 2021. The earlier iteration featured slim and flexible printed circuit boards in temporary tattoo form, but the boards had predefined behaviors and larger surface areas, making customizability a challenge.“There were several issues we didn’t address in SkinKit, such as how to allow users to program the modules the way they want to,” Ku said. “For SkinKit, everything was pre-programmed; users had to attach things in a certain order. With SkinLink, there is more customizability of the functions they like.”With SkinKit, for example, the circuitry had to be built before applying it to the body; with SkinLink, users can put one module on the body, then another, for more customizability.&nbsp;The SkinLink toolkit consists of functional circuit modules, made of flexible printed circuit boards, and flexible, custom-designed wiring (called trace modules, or traces) that connect the sensor and actuator modules to the microcontroller board.That’s a key difference from SkinKit: Smaller circuit boards are connect via flexible wiring, allowing for greater freedom of motion without sacrificing connectivity.&nbsp; “The circuit boards are somewhat rigid,” Ku said, “but we created the traces to be elastic, stretchable and flexible, so as not to hinder body movement.”The on-body fabrication process starts with selecting and programming the circuit board and trace modules. The microcontroller board can be repeatedly programmed during this step, to fine-tune the circuit functions. The boards can be temporarily placed on the body and customized, before final placement.The researchers conducted A/B testing of SkinLink, comparing its usability with SkinKit in a 14-person study, and found that SkinLink enables a more flexible wiring process than SkinKit, along with unrestricted circuit arrangement and superior wearability. Compared to the SkinKit, the SkinLink interface has a much smaller footprint, better stretchability, easier fabricating and more seamless wear.SkinKit, Kao said, offered a “low floor” – a term coined by computer scientist Ben Shneiderman, meaning that people with little or no experience can quickly get started designing and prototyping wearable tech. SkinLink takes it a couple of steps further, she said.“Another goal is what we call ‘high ceilings and wide walls,’” she said. “High ceilings means increasing the complexity of the prototypes; wide walls refers to the vast array of things that could be designed. That’s what I think SkinLink really does.”Kao said she sees both SkinLink and ECSkin as “enabling technologies,” with a variety of potential uses. Some of the studies with SkinLink involved artists, wearable tech researchers, and psychology researchers for physiology sensing; she also envisions applications beyond humans.&nbsp;“Being able to use this as a functional technology for physiological sensing or artistic practice is one application,” she said. “Our work has focused on skin interfaces for humans, but I think there could also be potential for designing ‘skin’ interfaces for other living beings, such as animals, and sensing for agricultural purposes, even on plants. We are interested in bringing SkinLink to broader disciplines to support on-skin prototyping.”

An ECSkin on-body display, composed of modular electrochromic films, is flexible and soft, and easily conforms to complex body parts such as the wrist. Hybrid Body Lab/Provided

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Neural spheroids — 3D clusters of brain cells — are emerging as essential tools for understanding neural networks and studying neurological diseases in the lab. EPFL’s e-Flower, a flower-shaped 3D microelectrode array (MEA), allows researchers to monitor the electrical activity of these spheroids in a way that was previously impossible. This breakthrough, <a href="https://www.science.org/doi/10.1126/sciadv.adp8054" target="_blank" rel="noopener">published in Science Advances</a>, lays the groundwork for more sophisticated research on brain organoids, which are complex, miniaturized models of brain tissues.<blockquote>Our flexible technology makes it possible to get accurate recordings without damaging the 3D neural models.<footer>Stéphanie P. Lacour</footer></blockquote>“The e-Flower lets us record neural activity from much more of the surface of neural spheroids in real-time — something that wasn’t possible with earlier tools. Our flexible technology makes it possible to get accurate recordings without damaging the 3D neural models, giving us a better understanding of how their complex circuits work,” says Stéphanie P. Lacour, lead author of the paper and head of the Laboratory for Soft Bioelectronic Interfaces (<a href="https://www.epfl.ch/labs/lsbi/">LSBI</a>) at the Neuro X Institute.<h2>Why neural spheroids?</h2>“We focused on neural spheroids for this study because they provide a straightforward and accessible model,” says Eleonora Martinelli, one of the lead researchers on the project.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1729211190818-9f9374f8.jpg" style="width: 100%px;" class="fr-fic fr-dib">Eleonora Martinelli says the goal is to apply the e-Flower to brain organoids. © 2024 EPFL / Alain HerzogNeural spheroids are three-dimensional clusters of neurons that replicate some of the key functions of brain tissue. They are simpler than organoids, which contain multiple cell types and more closely mimic the brain. The LSBI team at Campus Biotech worked in collaboration with Luc Stoppini and Adrien Roux at the&nbsp;<a href="https://www.hesge.ch/hepia/en/group/bioengineering" target="_blank" rel="noopener">Tissue Engineering Laboratory</a> (HEPIA-HESGE), researchers with long-standing experience with neural spheroids electrophysiology.“Spheroids are relatively easy to produce and manipulate in the lab, which makes them ideal for early-stage testing,” Martinelli continues. “However, our goal is to eventually apply the e-Flower to brain organoids, which more accurately model brain development and disorders.”“Organoids represent an exciting interface both for neuroscience research and next-generation neurotechnology,” says Stéphanie Lacour. “They bridge the gap between simplified in vitro models and the complexities of the human brain. Our work with the e-Flower is a critical step toward being able to explore these 3D models.”<h2>The serendipity behind the innovation</h2><blockquote>What was originally a problem for one project became the solution for another.<footer>Eleonora Martinelli</footer></blockquote>Interestingly, the e-Flower was born out of an unexpected discovery. Outman Akouissi, a collaborator on the project, encountered a challenge while working on soft implants for peripheral nerves: the hydrogels he used caused his devices to curl unpredictably when exposed to water. What started as a frustration turned into a breakthrough when Akouissi and Martinelli realized this curling mechanism could be harnessed for a completely different application — wrapping around neural spheroids.“This was a perfect example of how serendipity can lead to innovation,” says Martinelli. “What was originally a problem for one project became the solution for another.”<h2>A new approach to neural electrophysiology</h2>The device consists of four flexible petals equipped with platinum electrodes, which curl around the spheroid when exposed to the liquid that supports the cell structure. This actuation is driven by the swelling of a soft hydrogel, making the device both gentle on the tissue and easy to use.Designed to be compatible with existing electrophysiological systems, the e-Flower offers a plug-and-play solution for researchers, avoiding the need for complex external actuators or harmful solvents.Once the technology is applied to organoids, the ability to record electrical activity from all sides will provide a much more comprehensive understanding of brain processes. Researchers hope this will lead to new insights into neurodevelopment, brain injury recovery, and neurological diseases.<hr>ReferencesMartinelli, E., Akouissi, O., Liebi, L., Furfaro, I., Maulà, D., Savoia, N., Remy, A., Nikles, L., Roux, A., Stoppini, L., Lacour, S.P. "The e-Flower: A Hydrogel-Actuated 3D MEA for Brain Spheroid Electrophysiology." Science Advances, 2023. DOI:<a href="https://www.science.org/doi/10.1126/sciadv.adp8054" target="_blank" rel="noopener">10.1126/sciadv.adp8054</a>

EPFL researchers have developed a novel neural recording device called the "e-Flower" that gently wraps organoids in soft petals.

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<h2 id="isPasted">What is fashion tech? - diverse technologies and methods evolving the industry</h2><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1727662428032-img-0001+%282%29.jpg" style="width: 100%px;" class="fr-fic fr-dib">Providing new product value and customer experiences with technology“Fashion tech” is a term that combines fashion and technology. It refers to the use of big data, artificial intelligence (AI), augmented reality/virtual reality (AR/VR), and IT in customer services; the development of products incorporating functional materials and wearable devices; and the application of electronics and digital technologies in manufacturing, processing, and distribution processes.Fashion tech is expected to garner even more attention as a means to invigorate future consumption activities, products, industries, and markets as technology progresses and new products and services are introduced. As mentioned earlier, fashion tech is a broad term, but it can be classified into two categories based on its nature. One is the evolution of services and customer experiences (CX), and the other is the evolution of product functionality and manufacturing processes. We explain these two aspects of fashion tech in the following sections.<h2>Fashion tech evolving the customer experience (CX)</h2><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1727662469020-img-0002+%282%29.jpg" style="width: 100%px;" class="fr-fic fr-dib">An illustration of virtual fitting using ARIT and digital transformation (DX) are currently driving fashion tech. There have been many challenges in enhancing sales CX in stores and on e-commerce sites, but many of these have been addressed through IT and DX initiatives.For example, when selling clothing, shoes, jewelry, watches, eyewear, bags, etc., online, a longstanding issue has been the high hurdle for purchase decisions due to the difficulty for individual consumers to imagine how the actual products would look on them. However, in recent years, virtual fitting using AR (augmented reality) that can be easily used with cameras on smartphones and tablets has become widely adopted. Even without 3D data for products, the technology to enable three-dimensional representation in AR using artificial intelligence (AI) if multiple 2D images of the product are prepared has lowered the barrier to service introduction. In parallel with virtual fitting, services are now emerging whereby AI assesses how well eyewear and accessories suit a consumer based on the individual’s facial features and the item’s shape and size. These technological advances are driving the improvement of CX through the introduction of fashion tech.<img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1727662507296-img-0003+%282%29.jpg" style="width: 100%px;" class="fr-fic fr-dib">Leveraging RFID and AI to enhance CXFurthermore, the adoption of radio frequency identification (RFID) technology, including RFID tags and readers, is also advancing, and its applications are moving beyond rationalizing inventory management. RFID is being used to reduce checkout lines and payment hassles by simplifying self-checkout and to protect brands, such as by authenticating genuine products. Additionally, AI is being used to analyze customer and consumption trends across physical stores and e-commerce sites using RFID data. This enables swift response to customer needs through appropriate inventory adjustments. These are just some of the ways technology is being used. The related articles below explain more details.<h2>Fashion tech evolving product value and manufacturing processes through technology</h2>The DX and CX-oriented fashion tech mentioned above is expected to develop further. In addition, fashion tech that provides new added value to consumers through new characteristics and functions of materials and products is likely to garner more attention in the future due to advancements in materials, wearable devices, engineering, and manufacturing processes. Here, we introduce technologies such as digital fabrication, smart textiles, smart fabrics, and wearables, which are said to be key to the future development of fashion tech.<h3>Digital fabrication</h3><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1727662547797-img-0004+%283%29.jpg" style="width: 100%px;" class="fr-fic fr-dib">Example of the use of digital data and a 3D printerDigital fabrication is a general term for technologies that make or process products based on digital data. In fashion product manufacturing, it refers to using 3D scanners and 3D CAD to digitize product ideas and patterns and then importing the digitized data into digital manufacturing machines such as 3D printers and laser cutters to shape or process the ideas and patterns.Digital fabrication has attracted attention in recent years due to the diversification of needs and the development of digital technologies. By streamlining the design and manufacturing processes, digital fabrication has made it possible to accommodate high-mix, low-volume production and the manufacturing of personalized products. It is also gaining attention as a technology for providing new added value to products, such as the manufacturing and processing of materials with structures, functions, and properties that were not previously available.<h3>Smart fabrics (smart textiles)</h3><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1727662583771-img-0005+%281%29.jpg" style="width: 100%px;" class="fr-fic fr-dib">Providing new added value by imparting functionality to materials themselvesExpectations are rising for smart fabrics or smart textiles (hereinafter, smart fabrics), technologies that create new added value by imparting functionality to fashion products’ materials themselves. The digital fabrication mentioned earlier is also a means to realize these technologies.Smart fabrics generally refer to imparting functionality to fibers by integrating electronics technology. The functions are diverse. For example, the clothing itself may function as a sensor to monitor the wearer’s health condition, use electricity for sterilization, or regulate temperature. Various R&amp;D and commercialization efforts are underway to realize these functions. Many of these technologies are attracting attention for a wide range of purposes, such as health and medical care, sports and fitness, and safety improvement. The introduction of such technologies into everyday clothing is being plotted to provide new added value through fashion products with advanced functionality.

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Electronic waste, or e-waste, is a rapidly growing global problem, and it’s expected to worsen with the production of new kinds of flexible electronics for robotics, wearable devices, health monitors, and other new applications, including single-use devices.A new kind of flexible substrate material developed at MIT, the University of Utah, and Meta has the potential to enable not only the recycling of materials and components at the end of a device’s useful life, but also the scalable manufacture of more complex multilayered circuits than existing substrates provide.The development of this new material is described this week in the journal&nbsp;RSC: Applied Polymers, in a&nbsp;<a href="http://doi.org/10.1039/D4LP00182F" target="_blank">paper</a> by MIT Professor Thomas J. Wallin, University of Utah Professor Chen Wang, and seven others.“We recognize that electronic waste is an ongoing global crisis that’s only going to get worse as we continue to build more devices for the internet of things, and as the rest of the world develops,” says Wallin, an assistant professor in MIT’s Department of Materials Science and Engineering. To date, much academic research on this front has aimed at developing alternatives to conventional substrates for flexible electronics, which primarily use a polymer called Kapton, a trade name for polyimide.Most such research has focused on entirely different polymer materials, but “that really ignores the commercial side of it, as to why people chose the materials they did to begin with,” Wallin says. Kapton has many advantages, including excellent thermal and insulating properties and ready availability of source materials.The polyimide business is projected to be a $4 billion global market by 2030. “It’s everywhere, in every electronic device basically,” including parts such as the flexible cables that interconnect different components inside your cellphone or laptop, Wang explains. It’s also widely used in aerospace applications because of its high heat tolerance. “It’s a classic material, but it has not been updated for three or four decades,” he says.However, it’s also virtually impossible to melt or dissolve Kapton, so it can’t be reprocessed. The same properties also make it harder to manufacture the circuits into advanced architectures, such as multilayered electronics. The traditional way of making Kapton involves heating the material to anywhere from 200 to 300 degrees Celsius. “It’s a rather slow process. It takes hours,” Wang says.The alternative material that the team developed, which is itself a form of polyimide and therefore should be easily compatible with existing manufacturing infrastructure, is a light-cured polymer similar to those now used by dentists to create tough, durable fillings that cure in a few seconds with ultraviolet light. Not only is this method of hardening the material comparatively fast, it can operate at room temperature.The new material could serve as the substrate for multilayered circuits, which provides a way of greatly increasing the number of components that can be packed into a small form factor. Previously, since the Kapton substrate doesn’t melt easily, the layers had to be glued together, which adds steps and costs to the process. The fact that the new material can be processed at low-temperature while also hardening very quickly on demand could open up possibilities for new multilayer devices, Wang says.As for recyclability, the team introduced subunits into the polymer backbone that can be rapidly dissolved away by an alcohol and catalyst solution. Then, precious metals used in the circuits, as well as entire microchips, can be recovered from the solution and reused for new devices.“We designed the polymer with ester groups in the backbone,” unlike traditional Kapton, Wang explains. These ester groups can be easily broken apart by a fairly mild solution that removes the substrate while leaving the rest of the device unharmed. Wang notes that the University of Utah team has co-founded a company to commercialize the technology.&nbsp;“We break the polymer back into its original small molecules. Then we can collect the expensive electronic components and reuse them,” Wallin adds. “We all know about the supply chain shortage with chips and some materials. The rare earth minerals that are in those components are highly valuable. And so we think that there’s a huge economic incentive now, as well as an environmental one, to make these processes for the recapture of these components.”The research team included Caleb Reese and Grant Musgrave at the University of Utah, and Jenn Wong, Wenyang Pan, John Uehlin, Mason Zadan and Omar Awartani at Meta’s Reality Labs in Redmond, Washington. The work was supported by a startup fund at the Price College of Engineering at the University of Utah.

A new kind of flexible substrate material developed at MIT, the University of Utah, and Meta could help combat e-waste. Credit: Christine Daniloff, MIT; iStock

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