Toți ne place să ne simțim calzi în timpul iernii și să ne răcorim în timpul verii, ceea ce este exact cum se simte când purtați mătase
Textilul țesut cu fibre biomimetice are o izolație termică excelentă, o capacitate activă de electro-încălzire când este dopat cu nanotuburi de carbon (CNT), o bună uzură și o respirabilitate, făcându-l un material promițător pentru izolarea termică și gestionarea termică personală.Textile țesute cu astfel de fibre biomimetice prezintă o excelentă proprietate de izolare termică, precum și o bună aerisire și uzură.
Pe lângă izolarea pasivă a pierderilor de căldură, materialul textil ar putea funcționa și ca încălzitor care poate fi purtat cu materiale electrotehnice, cum ar fi CNT, pentru a determina reacția termică rapidă și electrofilarea uniformă, menținând în același timp caracterul moale și poros pentru o uzură confortabilă.
| osted: Feb 16, 2018 | |
Polar bear hair inspires nanotechnology enhanced thermal textile(Nanowerk News) Inspired by the microstructure and thermal insulation function of the polar bear hair, scientists have used a freeze-spinning technique to continuously fabricate silk fibroin solution into a fiber with aligned porous microstructure. |
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| The textile woven with the biomimetic fibers has an excellent thermal insulation, active electroheating capacity when doped with carbon nanotubes (CNTs), good wearability and breathability, making it a promising material for thermal insulation and personal thermal management. | |
| This work by researchers at Zhejiang University in China has been reported in Advanced Materials („A Thermally Insulating Textile Inspired by Polar Bear Hair”). | |
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| Polar bear hair with hollow core and aligned shell, and continuous and large-scale fabrication of biomimetic porous fiber. a) Photograph of a polar bear. b,c) SEM images showing the hollow core and aligned shell of a polar bear hair, respectively. d) Schematic illustration of the “freezespinning” technique, combining “directional freezing” with “solution spinning” to realize continuous and large-scale fabrication of biomimetic fibers with aligned porous structure, mimicking the polar bear hair. The silk fibroin solution extruded from a pump-controlled syringe is gradually frozen when it passes through a cold copper ring. Collected by a motor, the frozen fiber is further freeze-dried to reserve its porous structure and subsequently woven into a textile. e) Optical image showing a porous fiber collected in a roll. f,g) Optical (f) and SEM (g) images showing a woven textile of biomimetic porous fiber. The fiber diameter is around 200 µm. (© Wiley-VCH Verlag) (click on image to enlarge) | |
| The team uses a freeze-spinning method to realize continuous and large-scale fabrication of fibers with aligned porous structure, mimicking polar bear hairs, which is difficult to achieve by other methods. | |
| Textile woven with such biomimetic fibers shows an excellent thermal insulation property as well as good breathability and wearability. | |
| In addition to passively insulate heat loss, the textile could also function as a wearable heater, when doped with electroheating materials such CNTs, to induce fast thermal response and uniform electroheating while maintaining its soft and porous nature for comfortable wearing. |
| By Michael Berger – Michael is author of two books by the Royal Society of Chemistry: Nano-Society: Pushing the Boundaries of Technology and Nanotechnology: The Future is Tiny. |
au dezvoltat noi materiale nețesute care sunt conductive din punct de vedere electric, precum și flexibile și respirabile. Acest lucru deschide calea pentru hainele confortabile de înaltă tehnologie care, de exemplu, transformă lumina soarelui în căldură, pun la dispoziție dispozitive electronice portabile cu electricitate sau conțin senzori pentru antrenament de fitness.au reușit să producă materiale nețesute conductive din punct de vedere electric care au toate celelalte caracteristici pe care le-ați aștepta de la îmbrăcămintea potrivită pentru utilizarea zilnică. Materialele sunt flexibile și, astfel, se adaptează mișcărilor și modificărilor posturii. În plus, ele sunt permeabile la aer, ceea ce înseamnă că nu interferează cu respirația naturală a pielii.
| Posted: Feb 14, 2018 | |
Smart and comfortable new nanocomposite textiles for high-tech clothing(Nanowerk News) Uncomfortable, rigid, with low air permeability: textile materials capable of conducting electricity can be awkward for day-to-day use. However, researchers at the University of Bayreuth, Donghua University in Shanghai, and Nanjing Forestry University have now developed new nonwoven materials that are electrically conductive as well as flexible and breathable. This paves the way for comfortable high-tech clothes which, for example, convert sunlight to warmth, supply wearable electronic devices with electricity, or contain sensors for fitness training. |
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| The scientists have published their findings in the journal npj Flexible Electronics („Polymer nanofibre composite nonwovens with metal-like electrical conductivity”). | |
| Prof. Dr. Andreas Greiner’s team of researchers at the University of Bayreuth and their Chinese partners have succeeded in producing electrically conductive nonwovens which have all the other characteristics you would expect from clothing that is suitable for daily use. The materials are flexible, and thus adapt to movements and changes in posture. In addition, they are air-permeable, meaning they do not interfere with the natural breathing of the skin. | |
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| Prof. Dr. Andreas Greiner (left) and Prof. Dr. Seema Agarwal (right) with equipment for electrospinning at the University of Bayreuth. With backlighting, one can see the thin fibres from which nonwoven materials are formed. | |
| The combination of these properties is based on a special production process. In contrast to common methods of production, metal wires were not inserted into finished textiles. Rather, the scientists modified classical electro-spinning, which has been used to produce nonwovens for many years: short electro-spun polymer fibres and small amounts of tiny silver wires with a diameter of only 80 nanometres are mixed in a liquid. Afterwards, they are filtered, dried, and briefly heated up. If the composition is right, the resulting nonwoven material exhibits a very high degree of electrical conductivity. | |
| This opens up a whole range of possibilities for innovative applications, especially in the area of smart clothes (i.e. wearables). Everyday clothing, for example, can be equipped with solar cells such that the captured sunlight is converted to warmth, heating up the textiles themselves. Mobile phones, cameras, mini-computers, and other wearable electronic devices could be charged by plugging them into the textiles. Sensors installed in the clothes could provide athletes and trainers with important fitness and health data or could give family and friends information on its location. | |
| “In addition to articles of clothing, similar functions could also just as easily be installed in textile materials for use in seats and instruments in cars or airplanes,” explained Prof. Dr. Andreas Greiner, Chair of Macromolecular Chemistry II at the University of Bayreuth. | |
| “Our approach, which takes the production of conductive textiles as its basis, can in principle be applied to many different systems,” added Steffen Reich, doctoral researcher and lead author of the new study. As an example, he cites current Bayreuth research projects on microbial fuel cells, which could eventually be used as electrodes in such nonwoven materials. | |
| The research findings that were published in npj Flexible Electronics resulted from close cooperation between the University of Bayreuth, Donghua University in Shanghai, and Nanjing Forestry University. It was only two years ago that the University of Bayreuth signed a cooperation agreement with Donghua University, which has had a research priority on the research and development of textiles since the establishment of the institution. The mutual exchange in research and teaching that was agreed on is now beginning to bear fruit. |
| Source: University of Bayreuth |
Cercetatorii au integrat cu succes circuite electronice lavabile, stretchable si respirabil in tesatura, deschizand noi posibilitati pentru textile inteligente si electronice portabile. Circuitele au fost realizate cu cerneluri ieftine, sigure și ecologice și tipărite folosind tehnici convenționale de tipărire cu jet de cerneală.o forma bidimensionala a carbonului – poate fi imprimat direct pe tesatura pentru a produce circuite electronice integrate, care sunt confortabile si pot supravietui la 20 de cicluri într-o mașină de spălat tipică.cernelurile materiale bidimensionale, variind de la tehnologia de sănătate personală și de bunăstare, până la recoltarea și depozitarea energiei purtătoare, îmbrăcămintea militară, computerele portabile și moda.
| Posted: Nov 08, 2017 | |
Fully integrated circuits printed directly onto fabric(Nanowerk News) Researchers have successfully incorporated washable, stretchable and breathable electronic circuits into fabric, opening up new possibilities for smart textiles and wearable electronics. The circuits were made with cheap, safe and environmentally friendly inks, and printed using conventional inkjet printing techniques. |
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| The researchers, from the University of Cambridge, working with colleagues in Italy and China, have demonstrated how graphene – a two-dimensional form of carbon – can be directly printed onto fabric to produce integrated electronic circuits which are comfortable to wear and can survive up to 20 cycles in a typical washing machine. | |
| The new textile electronic devices are based on low-cost, sustainable and scalable inkjet printing of inks based on graphene and other two-dimensional materials, and are produced by standard processing techniques. The results are published in the journal Nature Communications („Fully inkjet-printed two-dimensional material field-effect heterojunctions for wearable and textile electronics”). | |
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| This is a sample circuit printed on fabric. (Image: Felice Torrisi) | |
| Based on earlier work on the formulation of graphene inks for printed electronics, the team designed low-boiling point inks, which were directly printed onto polyester fabric. Additionally, they found that modifying the roughness of the fabric improved the performance of the printed devices. The versatility of this process allowed the researchers to design not only single transistors but all-printed integrated electronic circuits combining active and passive components. | |
| Most wearable electronic devices that are currently available rely on rigid electronic components mounted on plastic, rubber or textiles. These offer limited compatibility with the skin in many circumstances, are damaged when washed and are uncomfortable to wear because they are not breathable. | |
| „Other inks for printed electronics normally require toxic solvents and are not suitable to be worn, whereas our inks are both cheap, safe and environmentally-friendly, and can be combined to create electronic circuits by simply printing different two-dimensional materials on the fabric,” said Dr Felice Torrisi of the Cambridge Graphene Centre, the paper’s senior author. | |
| „Digital textile printing has been around for decades to print simple colorants on textiles, but our result demonstrates for the first time that such technology can also be used to print the entire electronic integrated circuits on textiles,” said co-author Professor Roman Sordan of Politecnico di Milano. „Although we demonstrated very simple integrated circuits, our process is scalable and there are no fundamental obstacles to the technological development of wearable electronic devices both in terms of their complexity and performance.” | |
| „The printed components are flexible, washable and require low power, essential requirements for applications in wearable electronics,” said PhD student Tian Carey, the paper’s first author. | |
| The work opens up a number of commercial opportunities for two-dimensional material inks, ranging from personal health and well-being technology, to wearable energy harvesting and storage, military garments, wearable computing and fashion. | |
| „Turning textile fibres into functional electronic components can open to an entirely new set of applications from healthcare and wellbeing to the Internet of Things,” said Torrisi. „Thanks to nanotechnology, in the future our clothes could incorporate these textile-based electronics, such as displays or sensors and become interactive.” | |
| The use of graphene and other related 2D material (GRM) inks to create electronic components and devices integrated into fabrics and innovative textiles is at the centre of new technical advances in the smart textiles industry. The teams at the Cambridge Graphene Centre and Politecnico di Milano are also involved in the Graphene Flagship, an EC-funded, pan-European project dedicated to bringing graphene and GRM technologies to commercial applications. |
| Source: University of Cambridge |
oamenii de știință descriu modul în care utilizează o metodă de depunere a vaporilor pentru tesatura nano-strat pentru a crea sewable, materialul weavable, încălzit electric. Mânușa demonstrativă pe care au făcut-o poate menține degetele în picioare timp de până la opt ore. Mănușa cu trei straturi, cu un strat acoperit de polimerul conductor poli (3,4-etilendioxitiofen), cunoscut și ca PEDOT, este alimentat de o baterie cu buton de greutate de 1,8 grame. Un ban cântărește puțin sub 2,27 grame.Într-un test al capacității țesăturii de a rezista la crăpare, înfundare sau alte schimbări atunci când au fost încălzite, au generat o temperatură de 28 grade C (82,4 F), cu o conexiune la o baterie de 4,5 V și o temperatură de 45 grade C (113 F) -V pentru o oră și nu a găsit „modificări dramatice ale morfologiei”, ceea ce indică faptul că materialul de bumbac acoperit cu PEDOT a fost robust și suficient de stabil pentru a-și menține performanța „când este folosit ca element de încălzire.
| Posted: Sep 29, 2017 | |
Nanocoating makes electrically heated textiles possible(Nanowerk News) Commuters, skiers, crossing guards and others who endure frozen fingers in cold weather may look forward to future relief as manufacturers are poised to take advantage of a new technique for creating electrically heated cloth developed by materials scientist Trisha Andrew and colleagues at the University of Massachusetts Amherst. They have made gloves that keep fingers as warm as the palm of the hand. |
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| In a new paper in Applied Materials & Interfaces („Transforming Commercial Textiles and Threads into Sewable and Weavable Electric Heaters”), the scientists describe how they use a vapor deposition method for nano-coating fabric to create sewable, weavable, electrically heated material. The demonstration glove they made can keep fingers toasty for up to eight hours. The three-layered glove, with one layer coated by the conducting polymer poly(3,4-ethylenedioxytiophene), also known as PEDOT, are powered by a button battery weighing 1.8 grams. A dime weighs just under 2.27 grams. | |
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| A three-layered glove developed by materials chemist Trisha Andrew has one layer coated by the conducting polymer PEDOT and is powered by a button battery weighing 1.8 grams. (Image: UMass Amherst) | |
| The authors point out, „Lightweight, breathable and body-conformable electrical heaters have the potential to change traditional approaches to personal thermal management, medical heat therapy, joint pain relief and athletic rehabilitation.” | |
| Andrew says, „We took a pair of cotton gloves and coated the fingers to allow a small amount of current to pass through, so they heat up. It’s regular old-fashioned cotton cloth. We chose to make a pair of gloves because the fingers require a high curvature that allows us to show that our material is really flexible. The glove is powered by a small coin battery and they run on nano-amps of current, not enough to pass current through your skin or to hurt you. Our coating works even when it’s completely dunked in water, it will not shock you, and our layered construction means the conductive cloth does not come into contact with your skin.” | |
| She adds, „We hope to have this reach consumers as a real product in the next few years. Maybe it will be two years to a prototype, and five years to the consumer. I think this is the most consumer-ready device we have. It’s ready to take to the next phase.” | |
| Until recently, textile scientists have not used vapor deposition because of technical difficulties and high cost of scaling up from the laboratory. But recently, manufacturers are finding that the technology can be scaled up while remaining cost-effective, the researchers say. Using the vapor deposition method described in their paper, Andrew and colleagues also coated threads of a thick cotton yarn commonly used for sweaters. It performed well and offers another avenue for creating heated clothing, the authors state. | |
| Andrew says, „One thing that motivated us to make this product is that we could get the flexibility, the nice soft feel, while at the same time it’s heated but not making you sweaty. A common thing we hear from commuters is that in the winter, they would love to have warmer fingers.” In their laboratory tests, her research team reports, four fingers of the test glove warmed to the same temperature as the palm, and „the wearer could feel the heat transferred from the fabric heaters to her fingers a few seconds after the voltage was applied.” | |
| Andrew and chemistry postdoctoral researcher Lushuai Zhang, with chemical engineering graduate student Morgan Baima, conducted several tests to assure that their gloves could stand up to hours of use, laundering, rips, repairs and overnight charging. Andrew notes, „Right now we use an off-the-shelf battery that lasts for eight hours, but you would need a rechargeable to make these more practical.” | |
| Further, „If you are skiing and rip your glove, you can repair it just by sewing it back together with plain thread.” | |
| They arranged for biocompatibility testing at an independent lab where mouse connective tissue cells were exposed to PEDOT-coated samples and responses compared to positive and negative controls. They report that their PEDOT-coated materials are safe for contact with human skin without causing adverse reactions to the chemicals used. | |
| They also addressed questions of heat, moisture and skin contact stability to prevent the wearer from experiencing any electric shock from a wet conducting element. Andrew says, „Chemically, what we use to surround the conductive cloth looks like polystyrene, the stuff used to make packing peanuts. It completely surrounds the conducting material so the electrical conductor is never exposed.” | |
| Experimenting with different variables in the vapor nano-coating process, they found that adjusting temperature and chamber pressure were important in achieving optimal surface coverage of the cloth. In a test of the fabric’s ability to resist cracking, creasing or other changes when heated, they generated a temperature of 28 degrees C (82.4 F) with connection to a 4.5-V battery and 45 degrees C (113 F) connected to a 6-V battery for an hour, and found „no dramatic morphology changes,” indicating that the PEDOT-coated cotton textile was rugged and stable enough to maintain its performance” when used as a heating element. |
| Source: University of Massachusetts at Amherst | |
În timp ce în ultimul an nu a existat o revoluție în tehnologiile de armură a corpului, experții din industrie sunt de acord că au existat îmbunătățiri incrementale ale greutății și volumului total al soluțiilor de armură corporală
Cercetătorii au creat un material plastic cu costuri reduse, care ar putea deveni baza pentru îmbrăcăminte care răcește purtătorul
Combat tricou și pantaloni;Totul este conceput să facă parte dintr-un SISTEM, pentru a optimiza performanța atacatorului / operatorului
Cureaua TNVC / Unity Tactical CLUTCH este concepută special pentru transportul ascuns / ascuns pentru operatorii implicați în misiuni de operațiuni ascunse, dar se poate dubla ca o centură de combatere rapidă / reacție de urgență / tactică / luptă pentru operațiuni shooter activ / contraterorism
Materialul dezvoltat de Anthamatten și studentul absolvent Yuan Meng este un tip de polimer cu formă de memorie, care poate fi programat să păstreze o formă temporară până când este declanșat – de obicei prin căldură – pentru a reveni la forma sa originalăAnthamatten afirmă că polimerul cu formă de memorie ar putea avea o varietate de aplicații, inclusiv suturi, piele artificială, dozatoare medicale asistate de căldură și articole de îmbrăcăminte auto-asamblată.
| Posted: Feb 09, 2016 | |
Body temperature triggers newly-developed polymer to change shape(Nanowerk News) The material developed by Anthamatten and graduate student Yuan Meng is a type of shape-memory polymer, which can be programmed to retain a temporary shape until it is triggered—typically by heat—to return to its original shape. |
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| “Tuning the trigger temperature is only one part of the story,” said Anthamatten. “We also engineered these materials to store large amount of elastic energy, enabling them to perform more mechanical work during their shape recovery” | |
| The findings are being published this week in the Journal of Polymer Science Part B: Polymer Physics („Body temperature triggered shape-memory polymers with high elastic energy storage capacity”). | |
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| A time-lapse photo of a new shape-memory polymer reverting to its original shape after being exposed to body temperature. | |
| The key to developing the new polymer was figuring out how to control crystallization that occurs when the material is cooled or stretched. As the material is deformed, polymer chains are locally stretched, and small segments of the polymer align in the same direction in small areas—or domains—called crystallites, which fix the material into a temporarily deformed shape. As the number of crystallites grows, the polymer shape becomes more and more stable, making it increasingly difficult for the material to revert back to its initial—or “permanent”—shape. | |
| The ability to tune the trigger temperature was achieved by including molecular linkers to connect the individual polymer strands. Anthamatten’s group discovered that linkers inhibit—but don’t stop—crystallization when the material is stretched. By altering the number and types of linkers used, as well as how they’re distributed throughout the polymer network, the Rochester researchers were able to adjust the material’s stability and precisely set the melting point at which the shape change is triggered. | |
| Heating the new polymer to temperatures near 35 °C, just below the body temperature, causes the crystallites to break apart and the material to revert to its permanent shape. | |
| “Our shape-memory polymer is like a rubber band that can lock itself into a new shape when stretched,” said Anthamatten. “But a simple touch causes it to recoil back to its original shape.” | |
| Having a polymer with a precisely tunable trigger temperature was only one objective. Of equal importance, Anthamatten and his team wanted the material to be able to deliver a great deal of mechanical work as the shape transforms back to its permanent shape. Consequently, they set out to optimize their polymer networks to store as much elastic energy as possible. | |
| “Nearly all applications of shape memory polymers will require that the material pushes or pulls on its surroundings,” said Anthamatten. “However, researchers seldom measure the amount of mechanical work that shape-memory polymers are actually performing.” | |
| Anthamatten’s shape-memory polymer is capable of lifting an object one-thousand times its weight. For example, a polymer the size of a shoelace—which weighs about a gram—could lift a liter of soda. | |
| Anthamatten says the shape-memory polymer could have a variety of applications, including sutures, artificial skin, body-heat assisted medical dispensers, and self-fitting apparel. |
| Source: University of Rochester |
Read more: Body temperature triggers newly-developed polymer to change shape
inginerii mecanici ar putea reduce dependența de baterii de pe dispozitivele noastre mobile, asigurându-ne că avem putere pentru dispozitivele noastre, indiferent unde suntem.Tehnologia ar putea permite o combinație de energie încorporată în încălțăminte care să surprindă energia produsă de oameni în timpul mersului pe jos și să o stocheze pentru o utilizare ulterioară
