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Developing advanced engineering polymers that combine high strength and toughness represents not only a necessary path to excellence but also a major technical challenge. Here for the first time a rigid‐flexible interlocking polymer (RFIP) is reported featuring remarkable mechanical properties, consisting of flexible polyurethane (PU) and rigid polyimide (PI) chains cleverly woven together around the copper(I) ions center. By rationally weaving PI, PU chains, and copper(I) ions, RFIP exhibits ultra‐high strength (twice that of unwoven polymers, 91.4 ± 3.3 MPa), toughness (448.0 ± 14.2 MJ m−3), fatigue resistance (recoverable after 10 000 cyclic stretches), and shape memory properties. Simulation results and characterization analysis together support the correlation between microstructure and macroscopic features, confirming the greater cohesive energy of the interwoven network and providing insights into strengthening toughening mechanisms. The essence of weaving on the atomic and molecular levels is fused to obtain brilliant and valuable mechanical properties, opening new perspectives in designing robust and stable polymers. [ABSTRACT FROM AUTHOR]

Skin‐like optoelectronic devices have progressed in leaps and bounds, permitting considerable applications such as remote medical diagnosis, optical communication, biometric authentication, and 3D vision imaging. However, achieving extendable imaging in such frontier detectors poses a formidable challenge for stretchable electronic materials and remains largely unexplored. Herein, an ultrasensitive intrinsically stretchable organic photodiode is configured by the spatially modularizable‐assembled elastic photoactive film for faint near‐infrared light detection and extendable imaging. The performance metrics of the stretchable organic photodiodes rival that of commercial photodetectors, including high specific detectivity (D*noise) over 1012 Jones at 850 nm, ultralow noise current of 4.1 × 10−15 A Hz−1/2 and high stretchability up to 100%. Furthermore, it is the first time to simultaneously achieve the extendable near‐infrared cryptographic imaging and stable photoplethysmography signal detection based on stretchable photodiodes. These results signify a significant advancement toward enabling practical scenarios for stretchable organic optoelectronics. [ABSTRACT FROM AUTHOR]

Because of the complex nonlinear relationship between working conditions, the prediction of tribological properties has become a difficult problem in the field of tribology. In this study, we employed three distinct machine learning (ML) models, namely random forest regression (RFR), gradient boosting regression (GBR), and extreme gradient boosting (XGBoost), to predict the tribological properties of polytetrafluoroethylene (PTFE) composites under high-speed and high-temperature conditions. Firstly, PTFE composites were successfully prepared, and tribological properties under different temperature, speed, and load conditions were studied in order to explore wear mechanisms. Then, the investigation focused on establishing correlations between the friction and wear of PTFE composites by testing these parameters through the prediction of the friction coefficient and wear rate. Importantly, the correlation results illustrated that the friction coefficient and wear rate gradually decreased with the increase in speed, which was also proven by the correlation coefficient. In addition, the GBR model could effectively predict the tribological properties of the PTFE composites. Furthermore, an analysis of relative importance revealed that both load and speed exerted a greater influence on the prediction of the friction coefficient and wear rate. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: 2D covalent organic framework (2D‐COF), a modular three‐dimensional material, is easily influenced by the component module. The assembly of different functionalized modules gives 2D‐COF unique performance. The modular structure not only allows for customization but also allows for variety, which gives 2D‐COF a wide range of functions. Hence, many building blocks with catalytic, ligand, semiconductor, luminescent, and redox centers are integrated into the COF scaffold. The connection and assembly of such modules determine the nature of the final block material. The intra‐layer connections of the modules form a monolayer mesh chemical structure, and the subsequent stacking of the monolayer mesh structure produces the final crystalline porous material—2D‐COF. This review describes in detail the potential of COF materials as optoelectronic materials and our understanding of optoelectronic processes, starting from monolayer reticulation chemistry to final 3D stacked structures, thus establishing a new paradigm for the rational design of well‐defined novel 2D‐COF optoelectronic materials and devices. [ABSTRACT FROM AUTHOR]

Artificial sensory nerves can simulate the functions of visual perception and information processing of the human brain, which is indispensable for the immediate visualization of the environment and awareness requisite to avoid the potential harm. However, it still remains a long‐standing challenge to integrate recognition learning with real‐time processing function in a single device. Herein, an interface defects‐tuning strategy is proposed for developing a novel bi‐functional phototransistor. Benefiting from the tuned polymer‐perovskite layer‐heterointerface defects, the photogenerated charge trapping and de‐trapping capacities are significantly improved, thereby facilitating the photogenerated carrier separation and injection. The prepared organic‐inorganic hybrid phototransistors can perfectly mimic the human visual synaptic behaviors with a quick response speed (<35 ms, far below that of human eyes to incident light (225 ms)). More importantly, the phototransistor exhibited obvious visual adaptation toward wide‐ranging light stimuli, and realized unique desensitization to simulate the self‐protection behavior of the human visual systems. Specifically, the adaptation timescales of the device under dim and high light conditions are superior to bio‐systems (<2 min). Consequently, the reported strategy for the preparation of bi‐functional phototransistors provides a brand‐new perspective for next‐generation artificial nervous systems. [ABSTRACT FROM AUTHOR]