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Thermoset polymers are known for their superior thermomechanical properties, but the chemical crosslinking typically leads to intractability. This is reflected in the great differences between thermoset and thermoplastic shape-memory polymers; the former exhibit a robust shape memory but are not capable of redefining the permanent shape. Contrary to current knowledge, we reveal here that a classical thermoset shape-memory polyurethane is readily capable of permanent reshaping (plasticity) after a topological network rearrangement that is induced by transcarbamoylation. By employing the Jianzhi technique (also known as kirigami), unexpected shape-shifting versatility was observed for this otherwise classical material. As the essential carbamate moiety in polyurethanes is one of the most common polymer building units, we anticipate that our finding will have significant benefits beyond shape shifting. [ABSTRACT FROM AUTHOR]

Thermoset polymers are known for their superior thermomechanical properties, but the chemical crosslinking typically leads to intractability. This is reflected in the great differences between thermoset and thermoplastic shape-memory polymers; the former exhibit a robust shape memory but are not capable of redefining the permanent shape. Contrary to current knowledge, we reveal here that a classical thermoset shape-memory polyurethane is readily capable of permanent reshaping (plasticity) after a topological network rearrangement that is induced by transcarbamoylation. By employing the Jianzhi technique (also known as kirigami), unexpected shape-shifting versatility was observed for this otherwise classical material. As the essential carbamate moiety in polyurethanes is one of the most common polymer building units, we anticipate that our finding will have significant benefits beyond shape shifting. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high‐efficiency AWE. Herein, WC1‐x/Mo2C nanoparticle‐embedded carbon nanofiber (WC1‐x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1‐x, the electrocatalysts of WC1‐x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1‐x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm−2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d‐band center for WC1‐x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built‐in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high‐efficiency AWE. Herein, WC1‐x/Mo2C nanoparticle‐embedded carbon nanofiber (WC1‐x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1‐x, the electrocatalysts of WC1‐x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1‐x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm−2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d‐band center for WC1‐x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built‐in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields. [ABSTRACT FROM AUTHOR]

The traditional Chinese art of paper cutting, Jianzhi, also known as kirigami, generates beautiful and sophisticated patterns. In their Communication on page 11421 ff., Q. Zhao, T. Xie et al. made use of the Jianzhi technique to obtain classical thermoset polyurethanes with complex three‐dimensional shapes. The thermoset polymer has intrinsic plasticity and can be permanently and repeatedly reshaped in the solid state through a topological network rearrangement that is induced by transcarbamoylation. [ABSTRACT FROM AUTHOR]

Die traditionelle chinesische Kunst des Scherenschnitts, Jianzhi, führt zu wunderschönen und komplexen Mustern. In der Zuschrift auf S. 11593 ff. verwenden Q. Zhao, T. Xie et al. die Jianzhi ‐ Technik, um klassische duroplastische Polyurethane mit komplexen dreidimensionalen Formen zu erhalten. Das duroplastische Polymer zeichnet sich durch seine intrinsische Plastizität aus und kann durch eine topologische Netzwerk ‐ Reorganisation, die durch Transcarbamoylierung ausgelöst wird, permanent und wiederholt umgeformt werden. [ABSTRACT FROM AUTHOR]

We report herein an efficient method to synthesize 6-membered cyclic monothiocarbonates which are important intermediates for polymonothiocarbonate synthesis via the cycloaddition of carbonyl sulfide with 1,3-halohydrin using a low-cost base such as triethylamine and potassium carbonate. This protocol features excellent selectivity and efficiency, mild reaction conditions and easy-to-obtain starting materials. [ABSTRACT FROM AUTHOR]

Intelligent materials possess the function of self‐judgment and self‐optimization while sensing external stimuli such as stress, temperature, moisture, pH, electric or magnetic fields, or light. Besides, they often require self‐healing—the ability to repair damage spontaneously—or shape‐memory—the ability to return from a deformed state to their original shape induced by an external stimulus. Introducing such intelligence into superconducting (SC) devices is highly desirable to meet the critical requirement of maintenance‐free performance. Here, self‐healing and shape‐memory functions are realized in liquid metal based SC devices using smart packaging polymers. Without deteriorating their superconductivity, the SC devices can repair themselves by simply raising the temperature, without any other treatment. Beyond the specific functions achieved here, this work sheds new light on future SC devices with advanced functions such as self‐diagnosis, self‐adjusting, and sensing. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient way to fabricate reversible shape memory polymers via Digital Light Processing technology. • Allowing the construction of complex geometric shapes with reprogrammable shape-shifting performance. • Enabling regional control of reversible actuation beyond currently reported shape memory polymers. Reversible shape memory polymers (SMPs) have received extensive attention because of their unique deformation mechanisms and diverse shape-changing behaviors. However, the traditional methods of fabricating reversible SMPs usually result in the limitation of the accessible shapes and the corresponding shape-shifting behaviors. Herein, a reversible SMP with two crystalline phases is digital light-cured via thiol-acrylate chemistry with the assist of a digital light processing (DLP) technology. Thus, a set of special geometric patterns can be obtained by digitally defined exposure regions with a specified time, allowing the achievement of the 3D kirigami or origami reversible actuation. In addition, this strategy can be extended to the emerging advanced 3D or 4D printing technologies by introducing z-axis dimension or time gradient, facilitating the fabrication of sophisticated reprogrammable reversible shape memory devices, including 4D printed grabber and 3D printed movable cartoon character. Our approach based on DLP enables the rapid and precise manipulation of shape-changing materials, which can extend the possibilities for future development in aerospace and other potential applications. [ABSTRACT FROM AUTHOR]