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Interesting facts about plastics and rubber

We come across plastics and rubber everywhere in our daily lives. Discover fascinating stories, surprising facts and interesting background information – from historical developments and well-known products to key figures and innovations in the industry.

Results (423)

  • Global e-waste surging: Up 21% in 5 years

    The UN's 3rd Global eWaste Monitor reports 53.6 million metric tonnes (Mt) of e-waste was produced last year - substantially more than the weight of all adults in Europe. Global e-waste has risen 21% by weight in just five years, fueled by higher consumption rates of electric and electronic equipment, short life cycles, and few repair options. In 2030 the world is projected to produce about 50% more e-waste per capita compared with 2014. A record 53.6 million metric tonnes (Mt) of electronic waste was generated worldwide in 2019, up 21 per cent in just five years, according to the UN's Global E-waste Monitor 2020. The new report also predicts global e-waste - discarded products with a battery or plug - will reach 74 Mt by 2030, almost a doubling of e-waste in just 16 years. This makes e-waste the world's fastest-growing domestic waste stream, fueled mainly by higher consumption rates of electric and electronic equipment, short life cycles, and few options for repair. Only 17.4 per cent of 2019's e-waste was collected and recycled. This means that gold, silver, copper, platinum and other high-value, recoverable materials conservatively valued at US $57 billion - a sum greater than the Gross Domestic Product of most countries - were mostly dumped or burned rather than being collected for treatment and reuse. According to the report, Asia generated the greatest volume of e-waste in 2019, some 24.9 Mt, followed by the Americas (13.1 Mt) and Europe (12 Mt), while Africa and Oceania generated 2.9 Mt and 0.7 Mt respectively. Image: E-waste - discarded products with a battery or plug - will reach 74 Mt by 2030, almost a doubling of e-waste in just 16 years. This makes e-waste the world's fastest-growing domestic waste stream, fueled mainly by higher consumption rates of electric and electronic equipment, short life cycles, and few options for repair. (Quelle: Yassyn Sidki) Asia generated the greatest volume of e-waste in 2019, some 24.9 Mt, followed by the Americas (13.1 Mt) and Europe (12 Mt), while Africa and Oceania generated 2.9 Mt and 0.7 Mt respectively. Image: UN Global eWaste Monitor For perspective, last year's e-waste weighed substantially more than all the adults in Europe, or as much as 350 cruise ships the size of the Queen Mary 2, enough to form a line 125 km long. E-waste is a health and environmental hazard, containing toxic additives or hazardous substances such as mercury, which damages the human brain and / or coordination system. Other key findings from the Global E-waste Monitor 2020: Proper e-waste management can help mitigate global warming. In 2019, an estimated 98 Mt of CO2-equivalents were released into the atmosphere from discarded fridges and air-conditioners, contributing roughly 0.3 per cent of global greenhouse gas emissions In per capita terms, last year's discarded e-waste averaged 7.3 kg for every man, woman and child on Earth Europe ranked first worldwide in terms of e-waste generation per capita with 16.2 kg per capita. Oceania came second (16.1 kg) followed by the Americas (13.3 kg). Asia and Africa were much lower: 5.6 and 2.5 kg respectively E-waste is a health and environmental hazard, containing toxic additives or hazardous substances such as mercury, which damages the human brain and / or coordination system. An estimated 50 tonnes of mercury - used in monitors, PCBs and fluorescent and energy-saving light sources - are contained in undocumented flows of e-waste annually E-waste in 2019 was mainly comprised of small equipment (17.4 Mt), large equipment (13.1 Mt), and temperature exchange equipment (10.8 Mt). Screens and monitors, small IT and telecommunication equipment, and lamps represented 6.7 Mt, 4.7 Mt, and 0.9 Mt respectively Since 2014 the e-waste categories increasing fastest in total weight terms: temperature exchange equipment (+7 per cent), large equipment (+5 per cent), lamps and small equipment (+4 per cent). According to the report, this trend is driven by the growing consumption of those products in lower income countries, where those products improve the living standards. Small IT and telecommunication equipment have been growing more slowly, and screens and monitors have shown a slight decrease (-1 per cent), explained largely by lighter flat panel displays replacing heavy CRT monitors and screens Since 2014, the number of countries that have adopted a national e-waste policy, legislation or regulation in place has increased from 61 to 78. While a positive trend, this is far from the target set by the International Telecommunication Union which is to raise the percentage of countries with an e-waste legislation to 50 per cent The Global E-waste Monitor 2020 is a collaborative product of the Global E-waste Statistics Partnership (GESP), formed by UN University (UNU), the International Telecommunication Union (ITU), and the International Solid Waste Association (ISWA), in close collaboration with the UN Environment Programme (UNEP). The World Health Organization (WHO) and the German Ministry of Economic Cooperation and Development (BMZ) also substantially contributed to this year's Global E-waste Monitor 2020. Comments Image (r.): Cooling and heating devices (+7 per cent) have been the e-waste categories rising fastest in total weight terms since 2014, followed by large equipment (+5 per cent), lamps and small equipment (+4 per cent). driven by the growing consumption of those products in lower income countries. Small IT and telecommunication equipment have been growing more slowly, and screens and monitors have shown a slight decrease (-1 per cent), explained largely by lighter flat panel displays replacing heavy CRT monitors and screens. Source: UNU/UNITAR SCYCLE "The findings of this year's UNU-affiliated Global E-waste Monitor suggest that humanity is not sufficiently implementing the SDGs. Substantially greater efforts are urgently required to ensure smarter and more sustainable global production, consumption, and disposal of electrical and electronic equipment. This report contributes mightily to the sense of urgency in turning around this dangerous global pattern." - David M. Malone, Rector United Nations University (UNU) & UN Under Secretary General "Far more electronic waste is generated than is being safely recycled in most parts of the world. More cooperative efforts are required to make aware of this increasing issue and take appropriate countermeasures supplement by appropriate research and training. I am pleased that UNITAR now joins this important Global E-waste Statistics Partnership of UNU, ITU and ISWA, illustrating how valuable these activities are." - Nikhil Seth, Executive Director, United Nations Institute for Training and Research (UNITAR) & UN Assistant Secretary-General ''The Global E-waste Monitor highlights the pressing issue of e-waste management in today's digitally connected world in that the way we produce, consume, and dispose of electronic devices has become unsustainable. Monitoring e-waste streams will contribute to the achievement of the Sustainable Development Goals and tracking the implementation of the ITU Connect 2030 Agenda. The Monitor serves as a valuable resource for governments to improve their global e-waste recycling rate by developing the necessary/needed/required e-waste policies and legislation. ITU will continue to support the efforts made in this report towards the global response required in identifying solutions for e-waste." - Doreen Bogdan-Martin, Director, Telecommunication Development Bureau, International Telecommunication Union (ITU) "E-waste quantities are rising 3 times faster than the world's population and 13 per cent faster than the world's GDP during the last five years. This sharp rise creates substantial environmental and health pressures and demonstrates the urgency to combine the fourth industrial revolution with circular economy. The fourth industrial revolution either will advance a new circular economy approach for our economies or it will stimulate further resource depletion and new pollution waves. The progress achieved in e-waste monitoring by the Global E-waste Statistics Partnership is a sign of hope that the world can manage not only to monitor closely the e-waste rise but also to control their impacts and set up proper management schemes" - Antonis Mavropoulos, President, International Solid Waste Association (ISWA) "Informal and improper e-waste recycling is a major emerging hazard silently affecting our health and that of future generations. One in four children are dying from avoidable environmental exposures. One in four children could be saved, if we take action to protect their health and ensure a safe environment. WHO is pleased to join forces in this new Global E-waste Monitor to allow evidence, information about health impacts and joint solutions and policies to be made available to protect our future generations' health." - Maria Neira, Director, Environment, Climate Change and Health Department, World Health Organization (WHO

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  • Building a harder diamond

    Geometric structure of pentadiamond. White and black balls indicate C atoms with four and three adjacent C atoms, respectively. Image: University of Tsukuba Scientists at the University of Tsukuba create a theoretical carbon-based material that would be even harder than diamond. This work may have industrial applications for cutting and polishing in place of current synthetic diamond. Researchers at the University of Tsukuba used computer calculations to design a new carbon-based material even harder than diamond. This structure, dubbed "pentadiamond" by its creators, may be useful for replacing current synthetic diamonds in difficult cutting manufacturing tasks. Diamonds, which are made entirely of carbon atoms arranged in a dense lattice, are famous for their unmatched hardness among known materials. However, carbon can form many other stable configurations, called allotropes. These include the familiar graphite in pencil lead, as well as nanomaterials such as carbon nanotubes. The mechanical properties, including hardness, of an allotrope depend mostly on the way its atoms bond with each other. In conventional diamonds, each carbon atom forms a covalent bond with four neighbors. Chemists call carbon atoms like this as having sp3 hybridization. In nanotubes and some other materials, each carbon forms three bonds, called sp2 hybridization. Now, researchers at the University of Tsukuba have explored what would happen if carbon atoms were arranged in a more complex structure with a mixture of sp3 and sp2 hybridization. "Carbon allotropes with both sp2 and sp3 hybridized atoms have greater morphological diversity due to the huge number of combinations and arrangements in networks," says first author Yasumaru Fujii. To calculate the most stable atomic configuration, as well as estimate its hardness, the team relied on a computational method called density functional theory (DFT). DFT has been successfully used throughout chemistry and solid-state physics to predict the structure and properties of materials. Keeping track of the quantum states of all of the electrons in a sample, and especially their interactions, is usually an intractable task. Instead, DFT uses an approximation that focuses on the final density of electrons in space orbiting the atoms. This simplifies the calculation to make it suitable for computers, while still providing very precise results. The scientists found that the Young's modulus, a measure of hardness, of pentadiamond was predicted to be almost 1700 GPa, compared with about 1200 GPa for conventional diamond. "Not only is pentadiamond harder than conventional diamond, its density is much lower, equal to that of graphite," explains co-author Professor Mina Maruyama. "This work shows the power of designing materials ab initio. In addition to industrial cutting and drilling uses, pentadiamonds might be used in place of diamond anvil cells currently used in scientific research to recreate the extreme pressure inside planets" said senior co-author Professor Susumu Okada. Reference Fujii et al., Pentadiamond: A Hard Carbon Allotrope of a Pentagonal Network of sp2 and sp3 C Atoms, Physical Review Letters 125 (2020), http://dx.doi.org/10.1103/PhysRevLett.125.016001

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  • Scientists use a Teflon pipe to make a cheap, simple reactor for silica particle synthesis

    Experimental set-up of the microfluidic mixer for the continuous synthesis of SiO2 particles. Image: Yang Hui The synthesis of silica particles, used in bioimaging and drug delivery, could become considerably cheaper and more efficient by adopting a new flow synthesis method demonstrated by researchers in Australia and China, which involves a spiral channel and simple Teflon pipe to promote the rapid mixing of precursor fluids. Researchers in Australia and China have proposed an innovative and cost-effective new method for creating silica beads, which have a number of key uses, ranging from nanomedicine and bioimaging to the production of paper and polished concrete. The synthesis of silica particles for experimental and industrial uses began in the 1960s, and usually takes place in large batches, where controlled doping to induce functionality is difficult. Control of the synthesis parameters can be achieved through costly and time-consuming small-scale microfluidic reactors that require photolithography, etching, bonding and injection moulding, which are prone to clogging. Now, a surprisingly simple new approach has been demonstrated, and could be adopted for various applications at a low cost and with a high degree of reliability. Researchers at the ARC Centre of Excellence in Exciton Science, based at The University of Melbourne, and working with colleagues at South China Normal University, constructed a flow synthesis device using a polytetrafluoroethylene (PTFE) or 'Teflon' pipe wound around a rod and connected to two syringes. The key to the success of this approach is a spiral channel which promotes vortex flow characteristics, and this type of fluid flow encourages extremely efficient mixing of the precursor fluids. "When this happens you now have this very cheap and quite efficient chemical reactor," corresponding author Dr Eser Akinoglu said. "Once you have the fluids in a tube that is spiralled, then due to these vortexes, they mix very quickly and ... the overall reaction is more homogeneous, the product is homogeneous, and the silica particles have a uniform size and shape." While this new mechanism is unlikely to replace industrial-scale batch manufacturing for the creation of pure silica particles, it could well rival the microfluidic approach used in synthesising silica nanoparticles for specialised, niche applications, such as silica particles 'doped' with colourful dyes or encapsulating quantum dots for fluorescence. "From a material costs perspective, it's very reasonable," Dr Akinoglu said. "For the future, this flow synthesis method is ideal for the introduction of new components into the reaction ... you could put something else into this flow to mix together with the whole process and it will then be encapsulated in these silica particles." Reference Yang et al., A PTFE helical capillary microreactor for the high throughput synthesis of monodisperse silica particles, Chemical Engineering Journal (2020), http://dx.doi.org/10.1016/j.cej.2020.126063

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  • Researchers sharply reduce time needed for glass and ceramic 3D printing

    Interparticle photo-cross-linkable suspension enables 3D structuring of transparent SiO2 glass components through rapid heating profiles. Image: Motoyuki Iijima, Yokohama National University The fabrication of complex ceramic or glass structures via stereolithography, a type of 3D printing, has long been held back by how much time it takes at the back-end of the process, which can take up to two days. A new technique reduces this time down to less than 5 hours. Stereolithography prints objects from CAD files out of a powder suspended in a liquid. Objects are built layer by layer out of this liquid by shining a light, or laser, into the liquid-and-powder suspension, also called a "colloid." (Milk, for example, is also a colloid, but of milk fats suspended in water) The laser causes some of the particles that are sensitive to light to join up together, or "cross-link," and form layers made of particles embedded in polymers (long chains of molecules) - a hardening process called "curing." The laser in effect "writes" layers in the liquid suspension, and these layers, printed out on top of one another, form a 3D object composed of the binding agent and the powder. Ceramic or glass stereolithography holds the potential to fabricate parts with much more accurate and complex geometries--including hollow objects or ones with intricate internal structures that can reduce weight while maintaining strength--than could ever be achieved by conventional manufacturing with these substances. Such complexity of ceramic and glass design offers a raft of new biomedical, structural, and energy system applications. The cured object, termed 'green' once it has been printed, still has a couple of additional stages to go though at high temperature: debinding--or removal of its binding agents - and sintering - the fusing of the powder particles firmly together. After debinding, the object is termed 'brown', and the finished product can be obtained after sintering. However, in order to avoid structural collapse during this process--as a result of the production of gas bubbles that could shatter the strong but brittle ceramic or glass--debinding and sintering are performed extremely slowly, typically taking up to 48 hours. "Until now, this time-consuming and costly constraint has limited 3D printed glass and ceramic parts to highly specialized applications," said Motoyuki Iijima, an engineering researcher at Yokohama National University, whose team has developed a new colloid recipe that sharply reduces the time needed for debinding and sintering. "What you want instead is to get closer to the speed of conventional glass or ceramic production but combined with the complexity offered by 3D printing and similar additive manufacturing processes." The research team published their findings in the journal Communications Materials on May 20. To prove their recipe concept, the researchers wanted to manufacture transparent glass. This particular colloid recipe takes silica (SiO2) particles that have been modified with polyethyleneimine (a type of polymer) and oleic acid, a type of fatty acid that occurs in many animal and vegetable fats or oils. These particles are then mixed in an alcohol-based solvent along with a photo-initiator - the recipe ingredient that is sensitive to light and initiates the curing. Crucially, the recipe also allows for a much smaller amount of monomers - the particles that perform the cross-linking - than is normal in glass and ceramic stereolithography, and encourages more cross-linking by other particles. Normally, the large amount of monomers is what requires the slow debinding and sintering process because a rapid burning of monomers would generate the gas that threatens the structure of the object. By being able to use only tiny amounts of monomers in the colloid, the researchers managed to get the debinding and sintering time down to less than 5 hours. Having demonstrated how much faster this process can be performed for transparent glass, the researchers now want to extend the liquid suspension recipe, with its short processing time, to any kind of ceramic or glass. Reference Arita et al., Rapid three-dimensional structuring of transparent SiO2 glass using interparticle photo-cross-linkable suspension, Communications Material 1 (2020), http://dx.doi.org/10.1038/s43246-020-0029-y

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  • Growing polymers with different lengths

    It is hard to imagine everyday life without materials made of synthetic polymers. Clothes, car parts, computers or packaging - they all consist of polymer materials. Lots of polymers are present in nature, too, such as DNA or proteins. Polymers are built on a universal architecture: they are composed of basic building blocks called monomers. Polymer synthesis involves linking monomers together to form long chains. Imagine threading glass beads onto a string and creating chains of different length (and weight). Polymerization processes with limits An important industrial process for producing polymers is free radical polymerisation (FRP). Each year the chemical industry uses FRP to produce 200 million tonnes of polymers of various types, such as polyacrylic, polyvinyl chloride (PVC) and polystyrene. Although this production method has many advantages, it also has its limitations. FRP produces an uncontrollable mixture of countless polymers of different lengths; in other words, its dispersity is high. Dispersity is a measure of how uniform or non-?uniform the length of the polymer chains in a material is. Material's properties are determined to a large extent by this dispersity. In the case of everyday polymers, polymers with both low and high dispersity are required. In fact, for many high-?tech applications including pharmaceuticals or 3D printing, high dispersity can even be an advantage. Polymers with new properties However, if chemists want to produce polymer materials with very specific properties, they must first and foremost be able to adjust the dispersity as desired. This lets them produce a wide range of polymer materials that either contain uniform polymer species, i.e. have a low dispersity, or are highly dispersed with a great number of polymers of different lengths. Until now, this has hardly been possible. A group of researchers led by Athina Anastasaki, Professor of Polymer Materials at the Department of Materials Science, has now developed a method of controlling radical polymerisation, thus enabling researchers to systematically and completely control the dispersity of polymer materials. The results of their research were recently published in the journal Chem. In the past, in order to be able to control the radical polymerisation process at least to some extent, chemists would use a single catalyst. While this ensures that the resulting polymer chains become uniformly long, it doesn't allow the overall dispersity to be controlled as desired. Two catalysts do the trick Now the ETH researchers simultaneously employ two catalysts with different effects - one is highly active, the other only slightly active. This enabled them to adjust the dispersity precisely as a function of the ratio in which they mixed the two catalysts. If the more active catalyst was more abundant, more uniform polymers were produced, which meant the resulting material had low dispersity. If, however, the less active catalyst was more abundant, a large number of different polymer molecules were formed. This work means Anastasaki and her team have created a basis for the development of new polymer materials. In addition, their process is also scalable; it works not only in the laboratory, but also when applied to larger quantities of substances. Another advantage of this method is that even polymers with high dispersity can continue growing once the polymerisation process itself is complete - something that was previously considered impossible. The high efficiency and scalability of the approach have already attracted interest from industry. Polymers produced with the new process could be put to use in medicine, vaccines, cosmetics or 3D printing. Reference Whitfield R, Parkatzidis K, Truong NP, Junkers T, Anastasaki A: Tailoring Polymer Dispersity by RAFT Polymerization: A Versatile Approach. Chem, Vol. 6, Issue 6, P 1340-?1352, June 11th 2020. doi: 10.1016/j.chempr.2020.04.020, http://dx.doi.org/10.1016/j.chempr.2020.04.020

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  • Plastic in art, film, music and literature

    Topic of the Month Series launch: Plastics and art By Guido Deussing Sculpture by the French artist Niki de Saint Phalle (1930-2002) Despite all the prejudices: the chemistry between art and plastic is right! The use of synthetic materials does not make works of art “phoney” in any way. Accusing them of being artificial is wrong, because this would be based on the questionable requirement that art is supposed to be “natural”. History tells a different story: art has kept its distance from nature right from the start and has been undermining its authority step by step. Although art has superficially become more “artificial” in modern times with the introduction of plastic, this does not make it any less artistic – nature is not regaining any of the authority it has lost. While it is often the case that art theory is still battling with the issue of artificiality, art itself – and sculpture in particular – completed the integration process long ago in practice. Plastic sculptures experienced a veritable boom in the 1960s. Historically speaking, their history began before this, however: As long ago as 1916, the Russian sculptor Naum Gabo (1890 – 1977) created a sculpture called Tête No. 2 (Head No. 2) from Rhodoid (cellulose acetate, mainly used for billiard balls at the time) that was influenced by the cubist movement – in Paris, the city he chose to live in as his home. Art historians consider this to be a premiere – plastic was used as a material for artistic design for the first time. A short time later, Rhodoid was joined in the art world by celluloid, which catches fire easily, however – remember the early days of the cinema, when celluloid film went up in flames as soon as it got too hot in the projector (Source: Hamburg Film Museum). Transparent plastics create new potential Polymethyl methacrylate (PMMA), better known under its trade names Plexiglas, Lucite or Perspex, became available at the end of the 1920s too. The transparency of the new material made it possible for the visual arts to express themselves in completely new ways: light oscillation, which art enthusiasts normally ignore and sometimes even find distracting, now became part of the work of art and/or dissolved boundaries where spatial depth was concerned. A development that Gabo and Antoine Pevsner (1884 – 1962) had already anticipated on 5. August 1920 in their “Realistic Manifesto”: The two brothers declared that light and movement of it in an empty room were new sculptural tools and demanded elimination of the established materials. The manifesto marks the beginning of a tradition, a line that included László Moholy-Nagy (1895 – 1946), the constructivist who taught at Bauhaus in Weimar in the 1920s, and his „Space Modulator“ (1939) and can be traced all the way to the present (link to the chronological table) – e.g. to the German artists Adolf Luther (1912 – 1990, spherical concave mirror objects), Heinz Mack (born in 1930, luminokinetic art) or Uli Pohl (born in 1935, light sculptures made from plastic). Plastic – ideal material for the arts There are plenty of reasons for an artist to work with plastic and they are, first and foremost, completely pragmatic ones that have nothing to do with the effect they have and their spiritual significance. Plastic submits to practically all technical and aesthetic requirements. Its adaptability and versatility increase artistic design potential immensely and make it virtually a universal material: it is more pliable than glass, more malleable than wool and has the ability to imitate wood, stone, marble or metals exceptionally well and thus replace them. Artists frequently prefer plastic for cost reasons, on the one hand, because plastic is, after all, considerably less expensive than, say, bronze. On the other hand, natural materials always lose out where monumental art is involved, because no serious weight problems arise with light plastic – in contrast to marble or metal. The world-famous “Nanas” – colourfully painted sculptures of gigantic, corpulent women by the French artist Niki de Saint Phalle (1930 – 2002) – are unlikely to have spread so far without the weight advantage that polyester gave them either. This was, however, the only reason why Saint Phalle chose plastic: “I am not the slightest bit interested in the concept of plastic in itself or its ‘modern’ character. I paint it and people don’t know what kind of material it is. As far as I am concerned, the material is not important, it is a means to an end”, she admitted candidly (What artists say about plastic…). The fact that the basic substance was polyvinyl acetate in some cases and polyester resin in others also plays a secondary role in the lifelike human sculptures that the US sculptor Duane Hanson (1925 – 1996) created from the late 1960s onwards as representatives of the American way of life with the help of plaster casts. Because the material is always covered by clothing, ink and make-up. Inherent aesthetic qualities of the plastic are not apparent; the material is reduced to pure ‘fitness for purpose’. Sculpture by the French artist Niki de Saint Phalle (1930-2002). Source: Archiv Most artists grapple with the innovative new materials, on the other hand: “Plastics don’t have to look the way we encounter them day in, day out”, says the painter, sculptress and chemist Bussi Buhs, who was born in 1940 and teaches in Munich. “The only people who can prove this are artists who are willing to use their imagination and highlight the as yet still undiscovered sides of these organic materials – which combine in themselves the design potential of all other materials as ‘supermaterials’ that are felt to be colourfully female – by expressing them personally in their work.” What is important is to investigate the specific ways in which plastics articulate themselves and to enable them to “talk” in the work of art. New forms of expression are added to the art portfolio when these treasures are mined. Artistic autonomy is not surrendered here; the “language” of the plastic is not supposed to dictate the idea behind the work of art. In other words: the choice of material does not determine the artistic concept but vice-versa. The French sculptor César Baldaccini (1921 – 1998) stressed that the design of his “Expansions” made from polyurethane foam was determined by artistic creativity: “Once the process of the chemical reaction has been understood, the body starts to take action: this is physical, involving the hand. There are a thousand different ways to mould in order to produce very different shapes. There is also finishing by means of pressing that strengthens the surface. And I often make substantial changes in shape when I am doing this work. I can cut (up) the foam too and add a piece that has not been moulded yet. I can do whatever I want.” The pre-eminence of the idea applies to the light sculptures made of plastic created by the above-mentioned German sculptor Uli Pohl too: “It has been written that an object made of acrylic glass is first of all a transparent medium and that it is this transparency which transmits the light and reveals the surroundings. It should be pointed out by way of contrast that the design and the outcome of this are themselves the transport medium for the realisation of Pohl’s plastic ideas. Even his very first trials (‘models’) were not material tests with the aim of finding a possible design; instead of this, they were attempts to implement a specific concept.” (Quoted from the speech given by Dr Siegfried Salzmann [1928 – 1993] at the 1st Triennial for Small Sculptures in 1980, when he was Director of Wilhelm-Lehmbruck-Museum in Duisburg). Art made from plastic as a reflection of the time Irrespective of the autonomy of art: plastic is not a neutral material; it has a predetermined cultural and social context. The ideological attributes associated with it are not automatically abandoned as soon as art provides the framework. Plastic is considered to be modern, innovative, progressive – so it is no surprise that artists have associated utopian progress with the material too. US artists in particular have staged plastic: trendy, colourful and polished to a sheen. They have had to accept the criticism for doing this that they have given in to the pressure of the affluent society, since plastic has been considered the fruit and symbol of the focus on consumption and has been attacked for this. It is, however, more likely to be the case that art has merely held a mirror up to the society we live in. Critical responses like these do at any rate make it clear that there is greater pressure to justify the use of plastics as soon as resistance to our economic system starts to grow, as was the case from the end of the 1960s onwards. Synthetic materials were already frowned upon by system critics and environmental activists before the first oil crisis began in 1973. Interestingly enough, art was not paralysed by the anti-plastic trend; on the contrary, it even took advantage of it: plastic was used specifically to destroy the aura of the work of art, to desacralise it. Plastics were supposed to eliminate the quasi-religious, devotional approach art enthusiasts adopted in museums. The French artist and philosopher Hervé Fischer (born in 1941) went as far as to exhibit the remains of torn-up works of art in plastic sacks. And the Irish sculptor Les Levine (born in 1935) even advocated “disposable art” made from plastic that was supposed to be consumed. We think that goes much too far – both art and plastic are goods that are worth keeping (or at least recycling) Art and plastic: what artists say about plastic “Plastic is not a material that I like. It is a material I was forced to use because nothing else was available. It has to be said that this material is the only one in existence today that enables large, transportable volumes to be created: light and unbreakable.” Niki de Saint Phalle (1930 – 2002), French painter and sculptress, member of the Parisian group of artists “Nouveaux Réalistes”. First “Nanas” exhibition at the Galerie Alexandre Iolas, Paris, in September 1965 “What you have to say is more important than the material you use. The material must help to implement the idea. If plastics did not exist, this would not stop me working.” Armand Pierre Fernandez (1928 – 2005), known as Arman, French / US object artist and co-founder of “Nouveau Réalisme”. Became famous for his “Colères” (destroyed objects, incorporated and preserved in polyester resin) “Polyurethane – generally called foam plastic – has become the ideal vector for expressing concepts and ideas that correspond to my own attitude towards compression and density. Foam plastic is an interesting and very amusing material that appears to have an instinctive and sexual sense of humour.” John Angus Chamberlain, born in 1927, US artist (sculpture, film, photography). Representative of “Nouveau Réalisme” and “Abstract Expressionism”. Works with such materials as polyurethane and polymethyl methacrylate “Plastic is such an obviously modern material that many artists have believed it is enough simply to use plastics in order to update an outdated form of artistic expression and make it interesting. But although it is not capable of replacing a poor idea, this modern feel does exist, particularly when it is expressed technologically.” Hervé Fischer, born in 1941, French artist, cultural sociologist and philosopher. Established the movement “L’art sociologique” in 1971“ “In the final analysis, my work is done within the mechanical limits, the chemical laws of the materials that I use. The beauty that I am looking for is the beauty of simple scientific laws and the control of them by human beings.” Piotr Kowalski (1927 – 2004), Polish sculptor, started to live in Paris in 1953 and worked with plastics (polyester, acrylic resin) from 1957 onwards “To create something artistic from plastic, I think it is necessary to consider and really understand the main features of this material, its social application areas and its production potential. The manufacturing process became of greater interest to me than the object produced and I was of the opinion that this process had more to say about society and art than any aesthetic design or any work that an artist could create from it.” Les (Leslie Leopold) Levine, born in 1935, Irish sculptor, emigrated to Canada in 1958 and lives in New York. Works with polyester resin, polymethyl methacrylate and polystyrene “The aesthetic form of plastic products is generally developed by engineers and designers on the basis of their purpose. To my way of thinking, it is only possible to demonstrate what these materials – which have still not been investigated completely yet and still have to reveal their full potential – are capable of if purpose is ignored. I suspect that there is something profoundly erotic and sacred behind the Proteus-like ability of these materials to adapt to any form of mimicry and their ability to enter spiritual realms via transparency.” Bussi Buhs, born in 1940, German painter, sculptress and chemist; experiments with plastics from 1961 onwards, establishment and leadership of the plastics workshop at the Academy of Fine Arts in Munich from 1971 to 2005, lecturer for plastics technology. Works with such materials as polyester and acrylic “I am willing to use any material, any medium to make light directly or indirectly visible. Every material has to be dematerialised, so that the desired effect is achieved. Transparent materials like Plexiglas already have the ability to look immaterial as they are. This is why I used Plexiglas very often in the 60s. I abandoned this material when it was discovered by designers.” Academy of Fine Arts in Düsseldorf from 1950 to 1953, creative work in the luminokinetic art field since 1956, co-founder of the Düsseldorf group of artists known as “ZERO” in 1957

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  • Nanofiber masks can be sterilized multiple times without filter performance deterioration

    Schematic diagram on spraying and dipping treatments of face mask filters. Image: American Chemical Society There is a worldwide shortage of N95 masks. Scientists tested the effectiveness of reusing masks through disinfection with ethanol. They were able to verify that nanofiber nonwoven masks and filters can be sterilized multiple times at home without deterioration of the particulate collection performance. With the global spread of coronavirus infections, personal protective equipments especially hygeine face masks are receiving much attention. Masks are essential items for the primary protection of the respiratory tract from viruses and bacteria that are transmitted through the air as droplets. N95 masks are currently difficult to obtain, so there is an urgent need for a safe method of prolonging their usability through disinfection and reuse with minimal loss of the performance and integrity. Particulate filtration and air permeability are key factors in determining performance while cleaning and disinfecting N95 certified masks. This is crucial in preventing infections. Shinshu University has a track record of conducting research on production methods and applications of "nanofiber non-woven fabric" since before the coronavirus outbreak. With this current social backdrop, a research team led by Professor Ick Soo Kim of Shinshu University's Institute for Fiber Engineering (IFES) with Ph.D. students Sana Ullah and Azeem Ullah and Professor Cha Hyung Joon of POSTECH (specially invited professor of IFES) with Ph.D. students Jaeyun Lee and Yeonsu Jeong looked into the effectiveness of sterilizing N95 masks. They looked at commercially available melt-blown nonwoven fabric N95 masks and nonwoven nanofiber masks with N95 filters. They examined the filtration efficiency, comfort of the wearer, and filter shape change after washing and disinfecting. The methods of disinfection test were directly spraying 75% ethanol on the mask filter and air drying, and soaking the mask filter in 75% ethanol solution for 5 minutes to 24 hours and leaving it to air dry naturally. Evaluation of breathing comfort by infrared thermal camera. Image: American Chemical Society Filtration efficiency of both of the filters (melt-blown filter and the nanofiber filter) was 95% or more before use, which indicates that the respiratory organs of the wearer can be effectively protected. The tests also clarified that the inside of the filter can be effectively sterilized by spraying ethanol 3 times or more or immersing it in an ethanol solution for more than 5 minutes. However, when the mask was reused after the ethanol disinfection, the filtration efficiency of the melt-blown filter decreased to 64%. On the other hand, the nanofiber filter did not deteriorate in filter performance even after 10 or more uses. Melt-blown filter works on the principle of electrostatic charge for removal of particulate matter, as in the result of ethanol spraying or dipping the electrostatic charge on the surface of melt-blown filter was lost, so efficiency of melt-blown filter was significantly decreased. On the other hand, filtration mechanism of nanofiber filter is independent of static charge and fully dependent on pore diameter, pore distribution, and morphology of nanofibers. As in the result of disinfection, morphology of nanofibers was not affected, thus it also maintained it's filtration as optimum as it was before use. In addition, the nanofiber filter has higher heat emission and carbon dioxide emission performance than the melt-blown filter, and exhibits excellent breathability. Similarly, it was confirmed that the nanofiber filter had lower cytotoxicity than the melt-blown filter when a safety experiment using human skin and vascular cells was performed. Comparison of mask filter performance after ethanol disinfection: The nanofiber filter has air permeability even after being washed. The melt-blown filter has its mesh structure changed by ethanol sterilization and its performance is deteriorated. Image: American Chemical Society As stated above, both mask filters have similar filtering performance at the time of first use, but after disinfecting and reusing, the nanofiber filter does not exhibit performance deterioration. In other words, nanofiber filters can be easily sterilized with ethanol at home and reused multiple times. "This research is an experimental verification of the biological safety of nanofiber masks and the maintenance of filtration efficiency after washing, which has recently become a problem," Professor Cha Hyung Joon states, who co-presided the research. Professor Ick Soo Kim hopes that nanofiber masks will serve as a means of prevention in the second and third wave of coronavirus infections. Reference Ullah et al., Reusability Comparison of Melt-Blown vs Nanofiber Face Mask Filters for Use in the Coronavirus Pandemic, ACS Applied Nano Material (2020), https://doi.org/10.1021/acsanm.0c01562

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  • Exciting new developments for polymers made from waste sulfur

    Researchers at the University of Liverpool are making significant progress in the quest to develop new sulfur polymers that provide an environmentally friendly alternative to some traditional petrochemical based plastics. University of Liverpool chemist and Royal Society Research Fellow, Dr Tom Hasell and his team, have published two papers which demonstrate practical and exciting developments for sulfur polymer technologies and application. This new research builds on their game changing discovery in 2019 when they reported a new catalytic process to make polymers out of sulfur. Sulfur is a waste product from many industrial processes and in recent years a growing number of materials scientists have become interested in using it as an environmentally alternative to oil from which to manufacture plastics. As well as being in plentiful supply, sulfur also has the added advantage of leading to more easily recyclable polymers. In a paper published in Angewandte Chemie, Dr Hasell and colleagues make an exciting discovery that addresses the weakness of sulfur polymers, a factor that has limited its application. Led by PhD student Peiyao Yan, the paper demonstrates that adding a second type of bonding, urethane bonds, to the materials increases the strength of sulfur polymers by up to 135 times. The way this second type of bonding is introduced means that its amount can be controlled, and in turn controls the physical properties of the polymers. The strengthened sulfur polymers were found to have shape-memory effects - they can be set in one shape, before being temporarily deformed into another. When heated a little, they 'remember' the previous shape and go back to it. This setting process and temporary deformation can be repeated multiple times. This is a first for sulfur polymers, and despite these unusual properties, the sulfur bonds of the polymers mean they are still easy to recycle and opens up potential applications in areas such as soft robotics, medicine, and self-repairing objects. In a second paper, published in Chemical Science, Dr Hasell's group teamed up with researchers at Flinders University in Australia to show that sulfur polymers could form rubber like materials that could be easily self-repaired to their original strength within minutes, just by applying an amine catalyst that helps the bonds in the broken surfaces heal back together. This new kind of rubber and catalyst can be used with low energy consumption to make flexible, repairable, sustainable objects - providing a very real and useful application for these new sulfur polymers. Dr Tom Hasell said: "Both of these papers really show the potential of polymers made from waste sulfur to be a viable replacement material for some traditional petrochemical based plastics. "Not only as a substitute material, but as one that is easier to recycle, and has exciting new properties for materials chemists to explore. "We are excited to see what ideas researchers have for using these new findings, in particular the memory shape and "re-programming" properties." Reference Yan et al., Inverse Vulcanized Polymers with Shape Memory, Enhanced Mechanical Properties, and Vitrimer Behavior, Angewandte Chemie (2020), https://doi.org/10.1002/anie.202004311

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  • Polymers can fine-tune attractions between suspended nanocubes

    Colloids are complex mixtures in which microscopic particles of one substance are suspended evenly throughout another. They can be prepared in many different ways, but to achieve desirable properties in the final mixture, researchers must maintain a delicate control over the interactions which take place between the particles. In new research published in EPJ E, a team led by Remco Tuinier at the Eindhoven University of Technology in the Netherlands demonstrate this level of control for a type of colloid in which the suspended particles take the form of hollow, nanoscale cubes - a case which has only previously been explored through theoretical calculations. Such varieties of functional colloid can be useful in a range of technologies, including materials which manipulate the paths of light travelling through them, as well as highly sensitive light sensors. Their intricate preparation requirements can be achieved by adding in polymers which don't stick to the microparticles, creating zones of lower density around them. When these zones overlap, the particles become attracted to each other in characteristic ways. This behaviour can be finely tuned through three different techniques: adding polymer molecules in different concentrations; varying the size difference between particles and polymer molecules; and changing the particle shapes. For hollow silica nanocubes suspended in a solution containing molecules of polystyrene, Tuinier's team measured how the scattering of light passing through the mixture was affected by the polymer's concentration. Together with visual observations, this allowed them to assess the stability of the mixture. Altogether, they found that their experimental results agreed remarkably well with previous theoretical calculations. Their conclusions provide new insights into the diverse physics of colloidal mixtures, and could soon allow for new advances in technologies which sense and manipulate the flow of light. Reference F. Dekker, Á. González García, A.P. Philipse, R. Tuinier (2020), Phase stability of dispersions of hollow silica nanocubes mediated by non-adsorbing polymers, Eur. Phys. J. E 43:38. DOI 10.1140/epje/i2020-11962-y, http://dx.doi.org/10.1140/epje/i2020-11962-y

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  • Graphene smart textiles developed for heat adaptive clothing

    Graphene thermal smart materials. Image: The University of Manchester New research on the two-dimensional (2D) material graphene has allowed researchers to create smart adaptive clothing which can lower the body temperature of the wearer in hot climates. A team of scientists from The University of Manchester's National Graphene Institute have created a prototype garment to demonstrate dynamic thermal radiation control within a piece of clothing by utilising the remarkable thermal properties and flexibility of graphene. The development also opens the door to new applications such as, interactive infrared displays and covert infrared communication on textile. The human body radiates energy in the form of electromagnetic waves in the infrared spectrum (known as blackbody radiation). In a hot climate it is desirable to make use the full extent of the infrared radiation to lower the body temperature that can be achieved by using infrared-transparent textiles. As for the opposite case, infrared-blocking covers are ideal to minimise the energy loss from the body. Emergency blankets are a common example used to deal with treating extreme cases of body temperature fluctuation. The collaborative team of scientists demonstrated the dynamic transition between two opposite states by electrically tuning the infrared emissivity (the ability to radiate energy) of the graphene layers integrated onto textiles. One-atom thick graphene was first isolated and explored in 2004 at The University of Manchester. Its potential uses are vast and research has already led to leaps forward in commercial products including; batteries, mobile phones, sporting goods and automotive. The new research published today in journal Nano Letters, demonstrates that the smart optical textile technology can change its thermal visibility. The technology uses graphene layers to control of thermal radiation from textile surfaces. Professor Coskun Kocabas, who led the research, said: "Ability to control the thermal radiation is a key necessity for several critical applications such as temperature management of the body in excessive temperature climates. Thermal blankets are a common example used for this purpose. However, maintaining these functionalities as the surroundings heats up or cools down has been an outstanding challenge." Prof Kocabas added: "The successful demonstration of the modulation of optical properties on different forms of textile can leverage the ubiquitous use of fibrous architectures and enable new technologies operating in the infrared and other regions of the electromagnetic spectrum for applications including textile displays, communication, adaptive space suits, and fashion". This study built on the same group's previous research using graphene to create thermal camouflage which would fool infrared cameras. The new research can also be integrated into existing mass-manufacture textile materials such as cotton. To demonstrate, the team developed a prototype product within a t-shirt allowing the wearer to project coded messages invisible to the naked eye but readable by infrared cameras. "We believe that our results are timely showing the possibility of turning the exceptional optical properties of graphene into novel enabling technologies. The demonstrated capabilities cannot be achieved with conventional materials." "The next step for this area of research is to address the need for dynamic thermal management of earth-orbiting satellites. Satellites in orbit experience excesses of temperature, when they face the sun, and they freeze in the earth's shadow. Our technology could enable dynamic thermal management of satellites by controlling the thermal radiation and regulate the satellite temperature on demand." said Kocabas. Professor Sir Kostya Novoselov was also involved in the research: "This is a beautiful effect, intrinsically routed in the unique band structure of graphene. It is really exciting to see that such effects give rise to the high-tech applications." he said. Advanced materials is one of The University of Manchester's research beacons - examples of pioneering discoveries, interdisciplinary collaboration and cross-sector partnerships that are tackling some of the biggest questions facing the planet.

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  • Aerosol-printed graphene unveiled as low cost, faster food toxin sensor

    Researchers in the USA have developed a graphene-based electrochemical sensor capable of detecting histamines (allergens) and toxins in food much faster than standard laboratory tests. The team used aerosol-jet printing to create the sensor. The ability to change the pattern geometry on demand through software control allowed rapid prototyping and efficient optimization of the sensor layout. Commenting on the findings, which are published today in the IOP Publishing journal 2D Materials, senior author Professor Mark Hersam, from Northwestern University, said: "We developed an aerosol-jet printable graphene ink to enable efficient exploration of different device designs, which was critical to optimizing the sensor response." As an additive manufacturing method that only deposits material where it is needed and therefore minimizes waste, aerosol-jet-printed sensors are low-cost, straightforward to make, and portable. This could potentially enable their use in places where continuous on-site monitoring of food samples is needed to determine and maintain the quality of products, as well as other applications. Senior author Professor Carmen Gomes, from Iowa State University, said: "Aerosol-jet printing was fundamental to the development of this sensor. Carbon nanomaterials like graphene have unique material properties such as high electrical conductivity, surface area, and biocompatibility that can significantly improve the performance of electrochemical sensors. "But, since in-field electrochemical sensors are typically disposable, they need materials that are amenable to low-cost, high-throughput, and scalable manufacturing. Aerosol-jet printing gave us this." The team created high-resolution interdigitated electrodes (IDEs) on flexible substrates, which they converted into histamine sensors by covalently linking monoclonal antibodies to oxygen moieties created on the graphene surface by a CO2 thermal annealing process. They then tested the sensors in both a buffering solution (PBS) and fish broth, to see how effective they were at detecting histamines. Co-author Kshama Parate, from Iowa State University, said: "We found the graphene biosensor could detect histamine in PBS and fish broth over toxicologically-relevant ranges of 6.25 to 100 parts per million (ppm) and 6.25 to 200 ppm, respectively, with similar detection limits of 2.52 ppm and 3.41 ppm, respectively. These sensor results are significant, as histamine levels over 50 ppm in fish can cause adverse health effects including severe allergic reactions - for example, scombroid food poisoning. "Notably, the sensors also showed a quick response time of 33 minutes, without the need for pre-labelling and pre-treatment of the fish sample. This is a good deal faster than the equivalent laboratory tests." The researchers also found the biosensor's sensitivity was not significantly affected by the non-specific adsorption of large protein molecules commonly found in food samples and used as blocking agents. Senior author Dr Jonathan Claussen, from Iowa State University, said: "This type of biosensor could be used in food processing facilities, import and export ports, and supermarkets where continuous on-site monitoring of food samples is needed. This on-site testing will eliminate the need to send food samples for laboratory testing, which requires additional handling steps, increases time and cost to histamine analysis, and consequently increases the risk of foodborne illnesses and food wastage. "It could also likely be used in other biosensing applications where rapid monitoring of target molecules is needed, as the sample pre-treatment is eliminated using the developed immunosensing protocol. Apart from sensing small allergen molecules such as histamine, it could be used to detect various targets such as cells and protein biomarkers. By switching the antibody immobilized on the sensor platform to one that is specific towards the detection of suitable biological target species, the sensor can further cater to specific applications. Examples include food pathogens (Salmonella spp.), fatal human diseases (cancer, HIV) or animal or plant diseases (avian influenza, Citrus tristeza)." Reference Parate et al., Aerosol-jet-printed graphene electrochemical histamine sensors for food safety monitoring, 2D Materials 7 (2020), http://dx.doi.org/10.1088/2053-1583/ab8919

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  • Polymere ink of the future in printed electronics

    The energy levels of the two materials perfectly match, such that charges are spontaneously transferred from one polymer to the other, shown by Kai Xu and Simone Fabiano, Linköping University. Image: Thor Balkhed A research group led by Simone Fabiano at the Laboratory of Organic Electronics, Linköping University, has created an organic material with superb conductivity that doesn't need to be doped. They have achieved this by mixing two polymers with different properties. In order to increase the conductivity of polymers, and in this way obtain higher efficiency in organic solar cells, light-emitting diodes and other bioelectronic applications, researchers have until now doped the material with various substances. Typically, this is done by either removing an electron or donating it to the semiconductor material with a dopant molecule, a strategy that increases the number of charges and thereby the conductivity of the material. "We normally dope our organic polymers to improve their conductivity and the device performance. The process is stable for a while, but the material degenerates and the substances we use as doping agents can eventually leach out. This is something that we want to avoid at any cost in, for example, bioelectronic applications, where the organic electronic components can give huge benefits in wearable electronics and as implants in the body", says Associate Professor Simone Fabiano, head of the Organic Nanoelectronics group within the Laboratory of Organic Electronics at Linköping University. The research group, with scientists from five countries, has now succeeded in combining the two polymers, producing a conducting ink that does not require any doping to conduct electricity. The energy levels of the two materials perfectly match, such that charges are spontaneously transferred from one polymer to the other. The results have been published in Nature Materials. The blue one is the donor polymer solution, the red one is the acceptor. Both pristine polymers are non-conductive. When they meet each other, electrons from the donor polymer will automatically be transferred to the acceptor polymer, leaving free moving charges on both polymers. Image: Thor Balkhed "The phenomenon of spontaneous charge transfer has been demonstrated before, but only for single crystals on a laboratory scale. No one has shown anything that could be used at an industrial scale. Polymers consist of large and stable molecules that are easy to deposit from solution, and that's why they are well suited for large-scale use as ink in printed electronics", says Simone Fabiano. Polymers are simple and relatively cheap materials, and are commercially available. No foreign substances leach out from the new polymer mixture. It remains stable for a long time and withstands high temperatures. These properties are important for energy harvesting/storage devices as well as wearable electronics. "Since they are free of doping agents, they are stable over time and can be used in demanding applications. The discovery of this phenomenon opens completely new possibilities for improving the performance of light-emitting diodes and solar cells. This is also the case for other thermoelectric applications, and not least for research within wearable and close-body electronics", says Simone Fabiano. "We have involved scientists at Linköping University and Chalmers University of Technology, and experts in the US, Germany, Japan, and China. It has been a really great experience to lead this work, which is a large and important step in the field", he says. Principal funding for the research has come from the Swedish Research Council and the Wallenberg Wood Science Center. It has also been conducted within the framework for the strategic initiative in advanced functional materials, AFM, at Linköping University. "Fundamentally, doping in conducting polymers, generating high electrical conductivity, has so far only been achieved by combining a non-conducting dopant with a conducting polymer. Now, for the first time, the combination of two conducting polymers renders a composite system that is highly stable and highly conducting. This discovery defines a major new chapter in the field of conducting polymers, and will spark many novel applications and interest world-wide", says professor Magnus Berggren, director of Laboratory of Organic Electronics at Linköping University. References [1] https://www.nobelprize.org/prizes/chemistry/2000/8940-pressemitteilung-der-nobelpreis-in-chemie-2000/ [2] Xu et al., Ground-state electron transfer in all-polymer donor–acceptor heterojunctions, Nature Materials (2020), http://dx. doi. org/10. 1038/s41563-020-0618-7

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