Category: Chemistry

by Tokyo Institute of Technology

As we seek more efficient utilization of waste thermal energy, use of “phase change materials (PCMs)” is a good option. PCMs have a large latent heat capacity and the ability to store-and-release heat as they change from one state of matter to another. Among many PCMs, sugar alcohols (SAs), a class of organic compounds commonly used as sweeteners, stand out due to their low cost, non-toxic, non-corrosive, and biodegradable nature.

In particular, SAs generally have their melting point in 100–200 °C, which is an important temperature range where a huge amount of waste heat exists but is currently being discarded in our world.

However, SAs usually suffer from the issue of supercooling where, instead of solidifying, they remain in a liquid state even at temperatures well below the melting point. The supercooling degrades the quality (or “exergy”) of stored thermal energy because thermal energy at lower temperature has less usefulness. (Note: Thermal energy at room temperature is totally useless, no matter how much of it exists.)

Now, in a new study, researchers from Tokyo Institute of Technology (Tokyo Tech) led by Professor Yoichi Murakami have discovered that confining SAs in covalent organic framework (COF) crystals effectively resolves the issue of supercooling. Their findings, published in the journal Materials Horizons, have the potential to revolutionize SAs as heat-storage materials.

Dr. Murakami, who is a Professor at the Laboratory for Zero-Carbon Energy at Tokyo Tech, explains, “We propose a new materials concept with which the stored thermal energy can be retrieved at a much higher temperature than before, by largely mitigating the long-standing issue of supercooling that degrades the stored thermal energy. We have created a new class of solid-state PCMs based on abundant, non-toxic, and low-cost SAs.”

Normally, pure D-mannitol (Man), one of SAs, has a melting point of 167 °C, but it usually solidifies at random temperatures around 80–120 °C, which is a large supercooling of about 47–87 °C. To resolve this issue, the researchers introduced Man into the crystals of COF-300, one of the most typical COFs. They discovered that while the melting of Man confined in the COF occurred at around 150–155 °C, the freezing of the Man confined in the COF reproducibly occurred in the slightly lower temperature range of 130–145 °C. Therefore, the supercooling has been suppressed to only 10–20 °C, much smaller than the previous supercooling of about 47–87 °C.

“These results indicate that the fusion–freezing cycles of the Man–COF composite occur within a narrow temperature range of 130–155 °C without large or random supercooling,” says Prof. Murakami, highlighting the discovered effect of the COF confinement.

According to their published paper, earlier works confined SAs in rigid inorganic porous materials such as nanoporous silica and alumina to form solid-state PCMs, but they failed to resolve the supercooling issue of SAs. COFs are not only flexible porous materials but also have much smaller pores (in the order of single-nanometer scale) than those of previous inorganic nanoporous materials.

The present study is expected to pave the way for the new class of solid-state heat storage materials based on green and low-cost SAs for efficient thermal energy storage.

More information: Yoichi Murakami et al, Composite formation of covalent organic framework crystals and sugar alcohols for exploring a new class of heat-storage materials, Materials Horizons (2023). DOI: 10.1039/D3MH00905J

Journal information: Materials Horizons 

Provided by Tokyo Institute of Technology 

by University of Liverpool

New research by the University of Liverpool’s Chemistry Department represents an important breakthrough in the field of polymer science.

In their study, Liverpool researchers use mechanochemistry to characterize how a polymer chain in solution responds to a sudden acceleration of the solvent flow around it.

The paper, “Experimental quantitation of molecular conditions responsible for flow-induced polymer mechanochemistry,” is published in Nature Chemistry and is featured on the front cover.

This new approach answers a fundamental and technological question that has preoccupied polymer scientists for the past 50 years.

Since the 1980s, researchers have been trying to understand the unique response of dissolved polymer chains to suddenly accelerating solvent flows but had been constrained to highly simplified solvent flows that provided limited exploitable insights into the behavior of real-world systems.

The new discovery by Liverpool chemists Professor Roman Boulatov and Dr. Robert O’Neill has significant scientific implications for several areas of physical sciences as well as at a practical level for polymer-based rheological control used in many multi-million dollar industrial processes such as enhanced oil and gas recovery, long distance piping and photovoltaics manufacturing.

Professor Roman Boulatov said, “Our finding addresses a fundamental and technical question in polymer science and potentially upends our current understanding of chain behavior in cavitational solvent flows.”

Co-author of the paper, Dr. Robert O’Neill added, “Our proof-of-the-approach demonstration reveals that our understanding of how polymer chains respond to sudden accelerations of solvent flows in cavitating solutions was too simplistic to support systematic design of new polymer structures and compositions for efficient and economical rheological control in such scenarios or for gaining fundamental molecular insights into flow-induced mechanochemistry.

“Our paper has important implications for our ability to study non-equilibrium polymer chain dynamics at the molecular length scales, and thus our capacity to answer fundamental questions of how energy flows between molecules and within them, and how it transforms from kinetic to potential to free energies.”

The research team plans to focus on expanding the scope and capabilities of their new method and exploiting it to map molecular-level physics that would allow accurate predictions of flow behavior for an arbitrary combination of polymer, solvent and flow conditions.

More information: Robert T. O’Neill et al, Experimental quantitation of molecular conditions responsible for flow-induced polymer mechanochemistry, Nature Chemistry (2023). DOI: 10.1038/s41557-023-01266-2

Journal information: Nature Chemistry 

Provided by University of Liverpool 

by University of Science and Technology of China

Professor Huang Hanmin’s research team from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) proposed a new paradigm of metal electron-shuttle catalysis, which has been pioneeringly employed to achieve alkylative aminomethylation of unactivated alkene for the first time. Their work was published in Nature Catalysis on August 21.

Transition metal-catalyzed carbon-carbon bond formation has been an integral part of contemporary organic chemistry research. However, the development of transition metal-catalyzed C(sp³)-C(sp³) bond formation has been relatively slow due to the generation of unstable alkyl-metal intermediates during the reaction, which lead to various side reactions, making it difficult to apply the classical catalytic paradigm to C(sp³)-C(sp³) bond formation.

The dicarbofunctionalization of alkenes, where two carbon functional groups are introduced at both ends of the alkene in a single operation, has gained attention for its ability to efficiently connect carbon atoms, thereby facilitating the construction of complex molecules. Existing research is often limited to the introduction of C(sp²) functional groups, or they require the pre-installation of coordinating groups onto the alkenes to stabilize the alkyl-metal intermediates. This undeniably reduces the substrate applicability and step economy of the reaction.

To solve the challenges of alkene difunctionalization reactions, the research team proposed a new paradigm of metal electron-shuttle catalysis. Specifically, they utilized a metal catalyst as an electron shuttle to initiate and quench radicals, thereby achieving the construction of multiple alkyl-alkyl bonds through radical-unsaturated bond addition, effectively avoiding the generation of unstable alkyl-metal intermediates.

In this study, the team employed a nickel catalyst as the electron shuttle and used N, O-acetals and alkyl halides as the alkylating agents to accomplish the dialkylation of unactivated alkenes. This method demonstrated excellent compatibility with simple alkenes, unactivated alkenes and polysubstituted alkenes.

Additionally, various types of alkylating agents could be applied under such reaction conditions. Secondary amines and paraformaldehyde could also replace N, O-acetals in the four-component reaction, further broadening the scope of the reaction’s applications.

This reaction offers an efficient method for the synthesis of fluorinated and non-fluorinated δ-amino acids and other unnatural amino acid derivatives. Moreover, this reaction introduces various functional groups, which could further transform to produce more valuable complex molecules. For instance, by reducing and cyclizing the reaction products, one can swiftly construct piperidine compounds, which are prevalent in pharmaceutical molecules. Researchers synthesized the pharmaceutical molecule Mepazine and its corresponding fluorinated derivatives through this transformation strategy, demonstrating the practical value of the reaction.

This reaction not only offers significant synthetic applicability but also serves as an exemplar of the metal electron-shuttle catalysis paradigm, showcasing the promising prospects of this catalytic approach. Further research into the metal electron-shuttle catalysis will play a pivotal role in the development of drug and functional molecule synthesis.

More information: Changqing Rao et al, Double alkyl–alkyl bond construction across alkenes enabled by nickel electron-shuttle catalysis, Nature Catalysis (2023). DOI: 10.1038/s41929-023-01015-1

Journal information: Nature Catalysis 

Provided by University of Science and Technology of China

by ARC Centre of Excellence in Exciton Science

Achieving photochemical upconversion in a solid state is a step closer to reality, thanks to a new technique that could unlock vital innovations in renewable energy, water purification and advanced health care.

Exciton Science researchers based at UNSW Sydney have demonstrated that a key stage in the upconversion process can be achieved in the solid state, making it more likely that a functioning device can be manufactured at commercial scale. Possible applications include hydrogen catalysis and solar energy generation.

Their work has been published in ACS Energy Letters and is likely to drive major changes in the approach of scientists around the world researching this challenging but potentially transformational field.

Professor Tim Schmidt of UNSW Sydney, an Exciton Science Chief Investigator and the senior author on the paper, said, “I think people are going to immediately start copying us. I consider this a breakthrough because this approach can be adapted to upconverting into the ultraviolet or from the infrared. There’s so much we can do with it.”

Upconversion involves gluing two low-energy photons of light together to create more energetic, visible light, which can be captured by solar cells or harnessed for other purposes.

The technical term for the gluing process is “triplet-triplet annihilation,” which produces a “singlet exciton.” An exciton is a quasiparticle which exists when an electron and the hole it is bound to becomes excited by light or another source of energy.

Controlled and reliable triplet-triplet annihilation and the photochemical upconversion it enables could raise the efficiency limit of solar energy devices from 33.7% to 40% or beyond.

Much of the fundamental research on upconversion is performed with liquid samples. For the mechanism to be useful in real-world devices applications, it must be effectively demonstrated in a solid state.

In this work, Exciton Science Research Fellow Dr. Thilini Ishwara and her colleagues created a thin film of nanostructured alumina stained with a sensitizer.

The pores of the structure are filled with emitter molecules in concentrated solution, which allows a highly promising photon generation quantum yield of 9.4%.

The next step for the researchers is to move beyond the concentrated solution used in this approach and to achieve similar results in an entirely solid state, potentially by using a gel-like substance.

“If you can make it small enough, you could use it for even doing chemistry in the body,” Thilini said.

“You can generate higher energy light at a targeted place inside the body to treat tumors or create medicines with laser precision.

“Water purification is another use for upconversion. If you can upconvert the visible spectrum into quite a harsh UV, you can kill bugs and save millions of lives each year in the developing world.”

Other applications potentially able to be powered by new upconversion techniques include infrared technology like night vision, and even 3D printing.

More information: Thilini Ishwara et al, Nanoporous Solid-State Sensitization of Triplet Fusion Upconversion, ACS Energy Letters (2023). DOI: 10.1021/acsenergylett.3c01678

Journal information: ACS Energy Letters 

Provided by ARC Centre of Excellence in Exciton Science

by Martha Höhne, Leibniz Institute for Catalysis

Wouldn’t it be an elegant solution to use the substance that is most damaging to the climate and threatens the future as a raw material for economic goods and everyday items? In fact, carbon dioxide (CO₂), an unavoidable byproduct of civilization, is already being used in the laboratory to produce lower olefins, alcohols and fuels in combination with hydrogen and other chemical reactants, all of which can be obtained sustainably. For such processes to become industrial practice, they must be able to run under “fluctuating” conditions.

“Fluctuating” means that these processes must also function with fluctuating supplies of energy and starting materials. This is new for chemistry, but cannot be avoided if the energy, for example for the production of hydrogen by electrolysis, is to come from renewable sources such as sun and wind in the future. These are not available continuously and not at all on windless nights.

However, the influence of dynamic conditions on chemical reactions has hardly been studied so far, as Prof. Dr. Angelika Brückner and Prof. Dr. Evgenii Kondratenko at the Rostock Leibniz Institute for Catalysis explain. Their research group is involved with work on developing catalysts for CO₂ hydrogenation to higher hydrocarbons under fluctuating conditions.

From climate gas to raw material

In the grand scheme of things, the goal is to replace petroleum as a raw material base and at the same time to ennoble a problematic waste gas, carbon dioxide, into a raw material. But CO₂ is an inert gas and hardly reacts on its own.

To obtain commercially useful compounds, especially basic materials for the chemical synthesis of valuable products, the extremely stable carbon-oxygen bonds in CO₂ must be activated. This is done catalytically by hydrogenation, i.e., hydrogen is added, which can produce a variety of different hydrocarbon compounds. The more carbon atoms they contain in the molecule, the higher their valence.

For the process, the chemists modified the so-called Fischer-Tropsch synthesis, which was developed almost a hundred years ago for the hydrogenation of carbon monoxide (CO). To do this, they replaced the highly toxic CO with CO₂.

Iron catalyst changes

The structure and properties of the catalyst play a key role in determining which products are formed during CO₂ hydrogenation. In the case of Brückner and Kondratenko, it is an iron catalyst. But not all iron is the same, they say. They discovered that the catalyst changes in the reaction under fluctuating conditions: It keeps forming new “phases and species” in between, they say.

To precisely distinguish between favorable and obstructive phases, the researchers observe the catalyst at work, so to speak. This is done using highly specific operando-spectroscopic analysis methods based on infrared, UV and laser light. The catalyst samples are partly developed by the researchers themselves and partly obtained from their research partner at the Humboldt University in Berlin.

Catalytically, iron is often used in the form of oxides, explains Prof. Kondratenko. “But we prefer to obtain methane with it.” With the molecular formula CH₄, methane is the main component in natural gas and the simplest hydrocarbon. “However, we are after higher-value hydrocarbons, currently, for example, olefins.” These are indispensable basic chemicals that can be further refined chemically.

Active catalytic phase: Iron carbide

The Rostock scientists discovered that one phase in particular is crucial for CO₂ hydrogenation, in which iron carbide is formed at the catalyst surface. And they learned how to stabilize this carbide phase and avoid the interfering phases. For example, by using iron oxalate, an iron salt of oxalic acid (FeC₂O₄), instead of the usual iron oxide as the catalyst material. The team recently published two articles on this topic in Catalysis Science & Technology and the Journal of Catalysis.

A third publication of the group, in ACS Catalysis, reports on the problem of the decreasing activity of the iron catalyst. As a cause, the Rostock chemists discovered intermediates that convert to coke under certain circumstances. This is deposited as a tough layer on the catalyst surface and obscures the active species.

For future plants, the vision would be to convert the carbon dioxide right where it accumulates en masse and use it as a raw material, say Prof. Dr. Brückner and Prof. Dr. Kondratenko. In accordance with the principles of green chemistry and the circular economy, such a process would be particularly suitable in the environment of the currently largest CO₂ emitters, such as the cement industry, iron and steel production and the chemical industry itself, where the CO₂ can be further processed with “green” hydrogen into valuable hydrocarbons.

More information: Qingxin Yang et al, The role of Na for efficient CO2 hydrogenation to higher hydrocarbons over Fe-based catalysts under externally forced dynamic conditions, Journal of Catalysis (2023). DOI: 10.1016/j.jcat.2023.07.012

Andrey S. Skrypnik et al, Spatial analysis of CO2 hydrogenation to higher hydrocarbons over alkali-metal promoted iron(ii)oxalate-derived catalysts, Catalysis Science & Technology (2023). DOI: 10.1039/D3CY00143A

Qingxin Yang et al, Understanding of the Fate of α-Fe2O3 in CO2 Hydrogenation through Combined Time-Resolved In Situ Characterization and Microkinetic Analysis, ACS Catalysis (2023). DOI: 10.1021/acscatal.3c01340

Journal information: ACS Catalysis 

Provided by Leibniz Institute for Catalysis 

by Zhang Nannan, Chinese Academy of Sciences

Researchers from the Shanghai Institute of Ceramics of the Chinese Academy of Sciences, together with collaborators, have made a significant breakthrough in electrocatalytic water splitting, a key technology for converting intermittent solar and wind energy into clean hydrogen fuel.

According to the study published in Science Advances, quinary high-entropy ruthenium iridium-based oxide holds promise for large-scale application in proton exchange membrane water electrolyzer (PEMWE).

In the pursuit of a hydrogen society, electrocatalytic water splitting has emerged as a potential solution. However, the acidic operating environment of the proton exchange membrane (PEM) has posed challenges for the long-term use of ruthenium oxide (RuO₂). Now, the researchers led by Prof. Wang Xianying have discovered a quinary high-entropy five-membered ruthenium iridium-based oxide (M-RuIrFeCoNiO₂), which has promising applications in PEMWE.

They developed a unique synthesis strategy for M-RuIrFeCoNiO₂ to create abundant grain boundaries (GBs). This innovation significantly improves the catalytic activity and stability of RuO₂ in acidic oxygen evolution reactions (OER), overcoming previous limitations.

The deliberate integration of foreign metal elements and GBs into the oxide catalyst played a pivotal role in improving OER activity and stability. This groundbreaking approach effectively solves the thermodynamic solubility problems associated with different metal elements.

Practical application tests showed remarkable results, as a PEMWE using the M-RuIrFeCoNiO₂ catalyst maintained a high current density of 1 A cm^-2 for more than 500 hours. This achievement marks a significant advancement in PEMWE technology and holds promise for the large-scale production of clean hydrogen fuel.

This study not only demonstrates a novel synthesis strategy for high entropy oxides, but also provides valuable insights into their activity and stability in the context of PEMWE, contributing to the advancement of clean energy solutions.

More information: Chun Hu et al, Misoriented high-entropy iridium ruthenium oxide for acidic water splitting, Science Advances (2023). DOI: 10.1126/sciadv.adf9144

Journal information: Science Advances 

Provided by Chinese Academy of Sciences 

by KeAi Communications Co.

The transfer of plastic waste from land to oceans and its subsequent accumulation within the food chain poses a major threat to both the environment and human health. Consequently, the development of renewable, low-cost and eco-friendly alternative materials has garnered tremendous attention and interest.

Starch is a highly desirable material for the production of bioplastics due to its abundance and renewable nature. However, limitations such as brittleness, hydrophilicity and thermal properties restrict its widespread application.

Addressing these concerns, a group of researchers from State Key Laboratory of Pulp and Paper Engineering at South China University of Technology presents a novel strategy for fabricating a fully bio-based starch plastic that exhibits numerous advantages, including superior flexibility, waterproof capability, excellent thermal processability and self-adaptability.

“Native starch exhibits great stiffness due to the strong hydrogen bonding between its molecular chains, resulting in challenges during thermal processing,” explains Xiaoqian Zhang, the first author of the study published in Green Energy & Environment. “A covalent adaptable network was constructed to effectively weaken the hydrogen bonding and improve the stress relaxation of starch chains.”

“In the production of the fully bio-based starch plastic, dialdehyde starch was subjected to a mild Schiff base reaction with a plant oil-based diamine. This reaction resulted in the formation of dynamic imine bonds, which exhibited the ability to be cleaved and reformed reversibly under heat stimulation. Consequently, the starch plastic demonstrated remarkable thermal processability,” Zhang said.

“Additionally, the presence of long aliphatic chains in the diamine enhanced the steric hinderance of the starch molecule chains, leading to improved flexibility and hydrophobicity of the starch plastic.”

Xiaohui Wang, corresponding author of the study, added, “Our transparent starch plastic, which contains imine bonds, also demonstrates self-healing capability. It can repair not only scratches but also large-area damage with a simple heat-pressing treatment.”

Notably, the self-healing efficiency reached more than 88% in terms of mechanical properties. Such desirable properties render the starch plastic highly appealing for various practical applications. “Through this study, we have successfully introduced a novel design strategy for developing sustainable, thermal processable, and degradable bioplastics using fully bio-based materials,” concluded Wang.

More information: Xiaoqian Zhang et al, Flexible, thermal processable, self-healing, and fully bio-based starch plastics by constructing dynamic imine network, Green Energy & Environment (2023). DOI: 10.1016/j.gee.2023.08.002

Provided by KeAi Communications Co.

by National Institute of Standards and Technology

In movies, when we see fiery car crashes or flaming planes on runways, we know they are not real. But in the real world, fuel fires must be quenched with special kinds of chemicals, and the ones that have been most commonly used are known as aqueous film-forming foams (AFFFs). However, environmental and health concerns about AFFFs have launched widespread efforts to detect, monitor and eventually eliminate them. Now, researchers at the National Institute of Standards and Technology (NIST) have released new reference materials to expedite these efforts.

What makes the foams so effective are chemical compounds called per- and polyfluoroalkyl substances (PFAS), enabling them to suppress fuel fires much more quickly and efficiently compared with other alternatives. Unlike water dumped on a flame, which wouldn’t work in a scenario where a flammable liquid is causing the fire, the foams not only spread over the fire but prevent it from reigniting by suppressing oxygen flow and fuel vapors. AFFFs were first introduced in the 1940s and have been used since that time not only in emergencies but also in firefighter training exercises.

Due to their significant ability to resist heat and chemical changes, the PFAS in these foams break down slowly over time, giving them the name “forever chemicals.” The foams can easily leak into nearby water and soil and affect the surrounding ecology, raising concerns because PFAS have been linked to negative health effects such as certain cancers.

Because of these concerns, organizations including the Department of Defense (DOD) are starting to eliminate the use of PFAS-containing materials. Under the 2020 National Defense Authorization Act, the DOD will be required to stop purchasing AFFFs from manufacturers by October 2023 and will stop using them by October 2024.

To help with this phaseout, NIST researchers have collaborated with the DOD on a series of AFFF reference materials (RMs) containing PFAS. During the phaseout process, older AFFFs will still be around, and the RMs will help organizations identify foams with PFAS so they can remove them from use.

While manufacturers aim to meet the new military specifications for their foams to contain less than 1 parts per million (ppm) PFAS, “There are still legacy AFFFs sitting across the country, and they will need to have measurements made to show if they contain PFAS,” said NIST chemist Jessica Reiner. “If they do contain PFAS, then they will need to be disposed of properly.”

NIST has released four RMs containing different formulations of PFAS in the foams: RM 8690 PFAS in AFFF I, RM 8691 PFAS in AFFF II, RM 8692 PFAS in AFFF III, and RM 8693 PFAS in AFFF IV are available from NIST.

“These four RMs contain many of the different PFAS used in the legacy AFFFs that are being phased out. The RMs are useful for labs that want to test for these,” said Reiner.

The RMs will also help the military when purchasing alternative fire suppressants.

“Because the military has to stop purchasing these foams, they need to test for PFAS in the new foams that they buy. By having these RMs, they can measure for PFAS. Manufacturers producing new foams could also use the RM when they need to test if they are PFAS free,” said Reiner.

NIST researchers sent the RMs to a number of other labs to be tested in what’s called an interlaboratory study. They learned scientists had a hard time measuring PFAS in foam form. NIST researchers then designed the new reference materials in a specific way so that each individual formulation is diluted to make it easier to use.

Analytical labs, academic institutions, and the U.S. Department of Transportation are a few other examples of groups that can use the RMs. “For example, anyone in a toxicology group could use these RMs for scientific experiments, such as delivering doses of the compounds to study their effects on cells,” said Reiner.

Provided by National Institute of Standards and Technology 

by Tsinghua University Press

by Society of Chemical Industry

Scientists in China have fabricated a high-strength elastomer with self-healing properties. The polymer has significant potential in the field of flexible electronic devices.

In a study, published in Polymer International, researchers from a consortium of universities across Shanghai, China, have described a new poly(vinyl alcohol) (PVA)-based elastomer that can self-repair after damage, to maintain shape and performance. The flexible polymer is a solution to a longstanding issue with the durability of flexible electronic devices.

In recent years, flexible electronics have been attracting a lot of attention across multiple industries, with potential applications including flexible patch sensors to monitor blood glucose concentration, and flexible energy storage devices for wearable electronics. Currently however, the long-term stability of such materials is an issue, as Dr. Zili Li, Associate Professor at Fudan University, China, and corresponding author of the study, explained.

Speaking to SCI, he said, “Flexible polymer materials have been extensively explored in electronic devices, especially for health care and AI science. We want to solve the long-term reliability of the polymer matrix, which may be broken due to the external force damage, corrosion, or fatigue during operation.”

The study focuses on improving the properties of PVA, a polymer with excellent mechanical properties, but with poor stretchability and self-healing performance due to strong intramolecular and intermolecular bonds.

By using a one-step esterification reaction, the researchers added side chains onto the main PVA backbone, to create a graft polymer and subsequently incorporated Fe³⁺ ions into the matrix.

The resulting polymer had good stretchability (fracture elongation of 1565.0%) and self-healing performance (self-healing efficiency of 53.4% at room temperature) while maintaining excellent mechanical properties.

The team tested the performance of the graft polymer by coating the elastomers in a silver nanowire network to create a strain sensor. The resulting sensor exhibited high sensitivity and good self-healing performance. The authors noted that this result demonstrates “the wide potential applicability of the prepared PVA-based elastomers in health care, electrocardiography and safety monitoring.”

More information: Xingran Xu et al, Tailoring high mechanical performances of self‐healable poly(vinyl alcohol)‐based elastomers via judicious grafting of side chains, Polymer International (2023). DOI: 10.1002/pi.6515

Provided by Society of Chemical Industry