Summary Thermosets play a key role in the modern plastics and rubber industries, comprising ~20% of polymeric materials with a worldwide annual production of ~65 million tons. 1 , 2 The high density of crosslinks that gives thermosets their useful properties ( e.g ., chemical/thermal resistance, and tensile strength) comes at the expense of degradability and recyclability. Here, using the industrial thermoset polydicyclopentadiene (pDCPD) as a model system, we show that when a small number of cleavable bonds are selectively installed within the strands of thermoset plastics, the resulting materials can display the same mechanical properties as the native material, yet they are able to undergo triggered degradation to yield soluble, recyclable products of controlled size and functionality. In contrast, installation of cleavable crosslinks, even at comparably high loadings, does not produce degradable materials. These findings reveal cleavable bond location as a design principle for controlled thermoset degradation. Moreover, a new class of recyclable thermosets poised for rapid deployment is introduced.

Textbooks describe excess protons in liquid water as hydronium (HO) ions, although their true structure remains lively debated. To address this question, we have combined Raman and infrared (IR) multivariate curve resolution spectroscopy with ab initio molecular dynamics and anharmonic vibrational spectroscopic calculations. Our results are used to resolve, for the first time, the vibrational spectra of hydrated protons and counterions and reveal that there is little ion-pairing below 2 M. Moreover, we find that isolated excess protons are strongly IR active and nearly Raman inactive (with vibrational frequencies of ∼1500 ± 500 cm), while flanking water OH vibrations are both IR and Raman active (with higher frequencies of ∼2500 ± 500 cm). The emerging picture is consistent with Georg Zundel's seminal work, as well as recent ultrafast dynamics studies, leading to the conclusion that protons in liquid water are primarily hydrated by two flanking water molecules, with a broad range of proton hydrogen bond lengths and asymmetries.

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In recent decades, flexible, reconfigurable, and fast-response self-healing polymers have attracted considerable attention for both industrial field and scientific research. Mechanical blending remains the most mature, economical, effective, and the simplest approach to produce polymer blends, which can combine several distinctive advantages from different thermoplastic materials. However, such a process cannot be simply applied to thermosetting materials due to their permanent molecular structures. The synthesis of high-performance polymer blends connected by covalent cross-links remains a big challenge for the present industrial system. In this paper, we proposed a novel approach to synthesize polymer blends via blending thermosetting vitrimer containing dynamic covalent networks with thermoplastic polymers. It is demonstrated that the intrinsic relationship could be established by controlling the bond exchange reactions between the thermoset and the thermoplastic, thus triggering copolymerization. Due to the highly controlled processing conditions, the synthesized polymer is highly flexible, recyclable, and reprocessable, and possesses self-healing behavior at the same time. In addition, it shows potential applications in adhesive film and wearable electronics. This new technology opens a new way to reprocess thermoset in a fashion similar to thermoplastic in the current polymer industry.

Room temperature deformable PLA/TPU/PEG blends demostrate superior shape memory properties under low temperature environments due to the induced plasticizing effect.

Previous studies have suggested that leadership style may have an impact on job insecurity among employees. Authentic leaders encourage the development of the people around them by practicing real values, beliefs and behaviours, being subordinate oriented and making honest evaluations of the behaviour and performance of employees. Authentic leadership, often considered the ‘root construct’ of other positive leadership forms, conforms to Chinese culture and hence, may be the most suitable leadership style for organizations following this culture. As the effect of authentic leadership on job insecurity is unclear, this study aimed to examine the mechanism between job insecurity and authentic leadership and further explore the mediating effect of psychological empowerment and psychological capital. The results of this study, involving 451 employees from 68 departments of a communications enterprise in China, revealed that authentic leadership has a cross‐level negative impact on employees' job insecurity. Moreover, psychological empowerment and psychological capital played a multiple mediating role between authentic leadership and job insecurity.