Search Results (312)

Self-healing coatings can replace conventional coatings and are capable of self-healing and continuing to protect the substrate after coating damage. In this study, two types of self-healing resins were synthesized as coatings: Type-A via Diels–Alder crosslinking of furfuryl-modified diglycidyl ether bisphenol A with bismaleimide, and Type-B through epoxy blending/curing to form a semi-interpenetrating network. FTIR and Raman spectroscopy confirmed the formation of Diels–Alder (DA) bonds, while GPC tests indicated incomplete monomer conversion. Both resins were applied to glass and wood substrates, with performance evaluated through TGA, colorimetry (ΔE), gloss analysis, and scratch-healing tests (120 °C/30 min). The results showed that Type-A resins had a higher healing efficiency (about 80% on glass substrates and 60% on wood substrates), while Type-B resins had a lower healing rate (about 65% on glass substrates and 55% on wood substrates). However, Type-B is more heat-resistant, has a slower decomposition rate between 300 and 400 °C, higher gloss retention, and less color difference (ΔE) between wood and glass substrates. The visible light transmission of Type-B (74.14%) is also significantly higher. Full article

Traditional polyurethanes have gained widespread application due to their excellent mechanical properties, wear resistance, and processability. However, these materials are susceptible to cracking or fracture under environmental stresses. In recent years, self-healing polyurethanes have garnered significant attention as a critical research field owing to their key capabilities, such as repairing physical damage, restoring mechanical strength, structural adaptability, and cost-effective manufacturing. This review systematically examines the healing mechanisms, structural characteristics, and performance metrics of self-healing polyurethanes, with in-depth analysis of their repair efficacy across various applications—particularly in flexible electronic devices. It demonstrates that self-healing polyurethanes overcome traditional failure modes in flexible electronics through self-repair-function integration mechanisms. Their stimuli-responsive healing behavior is driving the evolution of this field toward an intelligent regenerative electronics paradigm. Full article

Conductive hydrogels hold great promise for biomedical and electronic applications. However, their practical use is often limited by poor self-healing capability, which can affect long-term stability and durability. To address this, we developed alginate/polyacrylamide-based conductive hydrogels incorporating FeCl₃ and AlCl₃, named CH-Fe and CH-Al, respectively. We systematically studied the influence of metal cations on the hydrogels’ mechanical and electrical properties. CH-Al showed the most optimized performance, with a 329% increase in tensile strength and a 323% improvement in conductivity compared to the blank hydrogel. Additionally, CH-Al demonstrated excellent self-healing ability, with nearly 100% recovery after damage. The introduction of Al³⁺ improved conductivity by forming dynamic electron-conductive pathways through interactions with the polymer network. The self-healing behavior arises from reversible metal–ligand coordination bonds, which enable rapid recovery of the hydrogel’s structure after mechanical disruption. This study successfully developed a conductive hydrogel that combines high electrical conductivity, robust mechanical strength, and an intrinsic self-healing ability, offering significant potential for applications in bioelectronic devices, flexible sensors, and implantable medical technologies. Full article

A novel self-healing brass powder/waterborne acrylic decorative coating for wooden substrates was developed, in which γ-methacryloxypropyltrimethoxysilane (KH570)-modified brass powder (with a coupling agent concentration of 6% and reaction solution pH of 5) was employed as the filler, and melamine-formaldehyde (MF) resin-encapsulated water-based paint microcapsules were utilized as the healing agent. The brass powder content and the core–wall ratio of the topcoat microcapsules were identified as the predominant factors affecting both the optical and mechanical properties of the self-healing brass powder/waterborne acrylic coating on Basswood surfaces. Therefore, the brass powder content was selected as the primary influencing factor. With concentration gradients of 0.5%, 1%, 3%, 5%, 7%, 9%, and 10%, and under constant conditions of 3% microcapsule content and room temperature curing, the effect of brass powder content on the properties of self-healing microcapsule coatings with different core–wall ratios was investigated. The waterborne acrylic wood coating containing 3% brass powder and 3% microcapsules with a core–wall ratio of 0.58:1 exhibited superior overall performance. This optimized formulation not only maintained excellent optical properties but also significantly enhanced mechanical performance, while preserving outstanding aging resistance, liquid resistance, and self-healing capability. The coating demonstrated the following comprehensive performance metrics: a glossiness of 24.0 GU, color difference (ΔE) of 2.13, chromatic aberration (ΔE*) of 13.68, visible light reflectance of 0.5879, dominant wavelength of 587.47 nm, visible light transmittance of 74.33%, pencil hardness of H grade, impact resistance of 2 kg·cm, adhesion rating of class 2, surface roughness of 2.600 μm, along with excellent aging resistance and liquid resistance properties, while achieving a self-healing efficiency of 19.62%. The coating also exhibited a smooth and uniform microscopic morphology, with the chemical bonds of both the modified brass powder and microcapsules remaining intact within the coating matrix. Full article

Maximizing hydrocarbon recovery from mature and complex reservoirs is constrained by heterogeneity, sand production, and harsh operational conditions. While polyacrylamide (PAM)-based systems are pivotal in addressing these challenges, a comprehensive synthesis of their transformative evolution and multifunctional capabilities remains overdue. This review critically analyzes advancements in PAM-based materials for enhanced oil recovery (EOR), conformance control, and sand management. We show that nanomaterial integration (e.g., magnetic NPs, nanoclays) significantly augments PAM’s rheological control, thermal and salinity stability, interfacial properties, and wettability alteration. Furthermore, the emergence of supramolecular chemistry has endowed PAM systems with unprecedented resilience, enabling self-healing and adaptive performance under extreme subsurface conditions. The review highlights a crucial paradigm shift towards integrated reservoir management, synergizing these advanced chemical designs with mechanical strategies and leveraging sophisticated monitoring and predictive analytics. Critically, innovations in sustainable and bio-inspired PAM materials offer environmentally responsible solutions with enhanced biodegradability. This synthesis provides a holistic understanding of the state of the art. Despite persistent challenges in scalability and predictability, continually re-engineered PAM systems are positioned as an indispensable and increasingly sustainable cornerstone for future hydrocarbon recovery in the complex energy landscape. Full article

Next-generation pilot suits are evolving into intelligent, adaptive platforms that integrate advanced polymeric materials, smart textiles, and on-body artificial intelligence. High-performance polymers have advanced in mechanical strength, thermal regulation, and environmental resilience, with fabrication methods like electrospinning, weaving, and 3D/4D printing enabling structural versatility and sensor integration. In particular, functional nanomaterials and hierarchical nanostructures contribute critical properties such as conductivity, flexibility, and responsiveness, forming the foundation for miniaturized sensing and integrated electronics. The integration of flexible fiber-based electronics such as biosensors, strain sensors, and energy systems enables real-time monitoring of physiological and environmental conditions. Coupled with on-body AI for multimodal data processing, autonomous decision-making, and adaptive feedback, these systems enhance pilot safety while reducing cognitive load during flight. This review places a special focus on system-level integration, where polymers and nanomaterials serve as both structural and functional components in wearable technologies. By highlighting the role of nanostructured and functional materials within intelligent textiles, we underline a potential shift toward active human–machine interfaces in aerospace applications. Future trends and advancements in self-healing materials, neuromorphic computing, and dynamic textile systems will further elevate the capabilities of intelligent pilot suits. This review discusses interdisciplinary strategies for developing pilot wearables capable of responding to real-time physiological and operational needs. Full article

Addressing the inherent brittleness of cement to mitigate infrastructure failures stemming from cracking is imperative. To accomplish both early crack resistance and subsequent self-healing capabilities, a biomimetic microstructure composed of a sodium polyacrylate (CSPA) network interwoven with hydration products was developed. The calcium-enriched polymer network formed via in situ polymerization of sodium acrylate (ANa) can enhance the mechanical properties of cement and achieve efficient self-healing of cracks. The porous structure of sodium polyacrylate (PANa) formed in pore solution at room temperature to simulate cement hydration conditions was observed by scanning electron microscopy (SEM). Feature peaks found by Fourier transform infrared (FTIR) spectroscopy as well as confocal Raman microscopy (CRM) suggested that ANa was polymerized successfully. Notably, CSPA samples demonstrated a remarkable 104% increase in flexural strength, attributed to the efficient transmission and dissipation of external forces along the polymer network embedded within the cement matrix. Additionally, after a 28-day hydration, CSPA specimens exhibited enhanced compressive strength compared to blank cement samples. This enhancement stems from the formation of a uniform polymer network, which effectively decreased the porosity and densified the microstructure of cement. Moreover, this organic–inorganic hybrid structure contributes to efficient crack healing, as the calcium-rich polymer network binds calcium ions and promotes the generation of healing products. The healing products consist of calcium hydroxide (CH), CaCO₃ (aragonite), C-S-H (calcium–silicate–hydrate), and PANa. Full article

Electroconductive, self-healing hydrogels have surfaced as a versatile tool for advanced wound care applications, since they combine classic hydrogels’ moist and biomimetic environment with the dynamic electrical responsiveness that can function as an accelerator of tissue repair processes. Recent advances report the automatic restoration of materials after mechanical disruption through various mechanisms, such as ionic or covalent bonds and supramolecular interactions. This property is crucial for biomaterials, as they are often applied in skin regions with high motility and, therefore, a high risk of breakage. By integrating within these networks compounds that are electrically active—polymers such as PEDOT:PSS or polypyrrole, or 2D nanomaterials such as graphene—it is possible to confer responsiveness to these hydrogels, which can lead to increases in fibroblast proliferation, antimicrobial properties, and angiogenesis. Furthermore, these biomaterials must have skin-mimicking mechanical properties and can also be loaded with drugs to improve their healing properties even further. This review synthesizes the chemistry behind the self-healing and electroconductive properties of these materials and expands on the available literature on this field and their biological outcomes, while also providing a look into the future of these promising materials, aiming at their integration in standard wound care strategies. Full article

The cement sheath is critical for ensuring the long-term safety and operational efficiency of oil and gas wells. However, complex geological conditions and operational stresses during production can induce cement sheath deterioration and cracking, leading to reduced zonal isolation, diminished hydrocarbon recovery, and elevated operational expenditures. This study investigates the development of a novel microbial self-healing well cement slurry system, employing fly ash as microbial carriers and sustained-release microcapsules encapsulating calcium sources and nutrients. Systematic evaluations were conducted, encompassing microbial viability, cement slurry rheology, fluid loss control, anti-channeling capability, and the mechanical strength, permeability, and microstructural characteristics of set cement stones. Results demonstrated that fly ash outperformed blast furnace slag and nano-silica as a carrier, exhibiting superior microbial loading capacity and viability. Optimal performance was observed with additions of 3% microorganisms and 3% microcapsules to the cement slurry. Microscopic analysis further revealed effective calcium carbonate precipitation within and around micro-pores, indicating a self-healing mechanism. These findings highlight the significant potential of the proposed system to enhance cement sheath integrity through localized self-healing, offering valuable insights for the development of advanced, durable well-cementing materials tailored for challenging downhole environments. Full article

The development of multifunctional conductive hydrogels with rapid self-healing capabilities and powerful sensing functions is crucial for advancing wearable electronics. This study designed and prepared a polyvinyl alcohol (PVA)–borax hydrogel incorporating carbon nanotubes (CNTs) and biomass carbon nanospheres (CNPs) as dual-carbon fillers. This hydrogel exhibits excellent conductivity, mechanical flexibility, and self-recovery properties. Serving as a highly sensitive piezoresistive sensor, it efficiently converts mechanical stimuli into reliable electrical signals. Sensing tests demonstrate that the CNT/CNP/PVA–borax hydrogel sensor possesses an extremely fast response time (88 ms) and rapid recovery time (88 ms), enabling the detection of subtle and rapid human motions. Furthermore, the hydrogel sensor also exhibits outstanding cyclic stability, maintaining stable signal output throughout continuous loading–unloading cycles exceeding 3200 repetitions. The hydrogel sensor’s characteristics, including rapid self-healing, fast-sensing response/recovery, and high fatigue resistance, make the CNT/CNP/PVA–borax conductive hydrogel an ideal choice for multifunctional wearable sensors. It successfully monitored various human motions. This study provides a promising strategy for high-performance self-healing sensing devices, suitable for next-generation wearable health monitoring and human–machine interaction systems. Full article

Microbial contamination is a global concern with impacts on a variety of industries ranging from marine to biomedical applications. Recent research on hydrophilic polymer-based coatings is focused on combining antifouling polymers with nanomaterials to enhance mechanical, optical, and stimuli-responsive properties, yielding colour changing, self-healing, and super hydrophilic materials. This study combines the hydrophilic and antifouling properties of vitamin B5 analogous methacrylamide (B5AMA)-based polymers with stimuli-responsive anthocyanin-dye-loaded cellulose nanocrystals (CNCs) to develop antifouling materials with colour changing capabilities upon bacterial contamination. Poly(B5AMA)-grafted CNCs were prepared through surface-initiated photoiniferter reversible addition fragmentation chain transfer (SP-RAFT) polymerization and characterized through proton nuclear magnetic resonance (¹H-NMR), transmission electron microscopy (SEM/TEM), and X-ray photon spectroscopy (XPS) to confirm the formation of surface-grafted polymer chains. The bare CNCs and poly(B5AMA)-grafted CNCs were loaded with anthocyanin dye and evaluated for pH-dependent colour changing capabilities. Interestingly, anthocyanin-loaded CNCs demonstrated vibrant colour changes in both solution and dried film form upon bacterial contamination; however, limited colour changing capabilities of the composites, specifically in dried film form, were attributed to the enhanced dispersibility and antifouling capabilities of the polymer-coated CNCs. Full article

The rapid growth in large-scale distributed video conferencing, remote education, and real-time broadcasting poses significant challenges to traditional centralized streaming systems, particularly regarding scalability, cost, and reliability under high concurrency. Centralized approaches often encounter bottlenecks, increased bandwidth expenses, and diminished fault tolerance. This paper proposes a novel decentralized real-time broadcasting system employing a peer-to-peer (P2P) chain topology based on IPv6 networking and the Secure Reliable Transport (SRT) protocol. By exploiting the global addressing capability of IPv6, our solution simplifies direct node interconnections, effectively eliminating complexities associated with Network Address Translation (NAT). Furthermore, we introduce an innovative chain-relay transmission method combined with distributed node management strategies, substantially reducing reliance on central servers and minimizing deployment complexity. Leveraging SRT’s low-latency UDP transmission, packet retransmission, congestion control, and AES-128/256 encryption, the proposed system ensures robust security and high video stream quality across wide-area networks. Additionally, a WebSocket-based real-time fault detection algorithm coupled with a rapid fallback self-healing mechanism is developed, enabling millisecond-level fault detection and swift restoration of disrupted links. Extensive performance evaluations using Video Multi-Resolution Fidelity (VMRF) metrics across geographically diverse and heterogeneous environments confirm significant performance gains. Specifically, our approach achieves substantial improvements in latency, video quality stability, and fault tolerance over existing P2P methods, along with over tenfold enhancements in frame rates compared with conventional RTMP-based solutions, thereby demonstrating its efficacy, scalability, and cost-effectiveness for real-time video streaming applications. Full article

Fault detection and remaining useful life (RUL) prediction are critical tasks in self-healing network (SHN) environments and industrial cyber–physical systems. These domains demand intelligent systems capable of handling dynamic, high-dimensional sensor data. However, existing optimization-based approaches often struggle with imbalanced datasets, noisy signals, and delayed convergence, limiting their effectiveness in real-time applications. This study utilizes two benchmark datasets—EFCD and SFDD—which represent electrical and sensor fault scenarios, respectively. These datasets pose challenges due to class imbalance and complex temporal dependencies. To address this, we propose a novel hybrid framework combining Attention-Augmented Convolutional Neural Networks (AACNN) with transformer encoders, enhanced through Enhanced Ensemble-SMOTE for balancing the minority class. The model captures spatial features and long-range temporal patterns and learns effectively from imbalanced data streams. The novelty lies in the integration of attention mechanisms and adaptive oversampling in a unified fault-prediction architecture. Model evaluation is based on multiple performance metrics, including accuracy, F1-score, MCC, RMSE, and score*. The results show that the proposed model outperforms state-of-the-art approaches, achieving up to 97.14% accuracy and a score* of 0.419, with faster convergence and improved generalization across both datasets. Full article

Postoperative adhesions are a prevalent complication following abdominal surgeries, often leading to significant clinical challenges. This study introduces an innovative solution utilizing a polyethylene glycol (PEG)-based triblock copolymer to form an injectable, self-healing hydrogel aimed at preventing these adhesions. The hydrogel, formulated with temperature-responsive and self-healing properties through the incorporation of poly (N-isopropyl acrylamide) (PNIPAM) and anion–pi interactions, was synthesized using reversible addition–fragmentation chain transfer (RAFT) polymerization. The hydrogel’s physical properties, biocompatibility, hemostatic effect, and anti-adhesive capabilities were rigorously tested through in vitro and in vivo experiments involving rat models. It demonstrated excellent biocompatibility, effective tissue adhesion, and robust hemostatic properties. Most notably, it exhibited significant anti-adhesive effects in a rat abdominal wall–cecum model, reducing adhesion formation effectively compared to controls. The PEG-based injectable hydrogel presents a promising approach for postoperative adhesion prevention. Its ability to gel in situ triggered by body heat, coupled with its self-healing properties, provides a substantial advantage in clinical settings, indicating its potential utility as a novel anti-adhesion material. Full article

This paper reviews the applications and performance advantages of ultra-high-performance concrete (UHPC), engineered cementitious composite (ECC), and recycled aggregate concrete (RAC) in composite flexural members. UHPC is characterized by its ultra-high strength, high toughness, excellent durability, and microcrack self-healing capability, albeit with high costs and complex production processes. ECC demonstrates superior tensile, flexural, and compressive strength and durability, yet it exhibits a lower elastic modulus and greater drying shrinkage strain. RAC, as an eco-friendly concrete, offers cost-effectiveness and environmental benefits, although it poses certain performance challenges. The focus of this review is on how to enhance the load-bearing capacity of composite beams or slabs by modifying the interface roughness, adjusting the thickness of the ECC or UHPC layer, and altering the cross-sectional form. The integration of diverse concrete materials improves the performance of beam and slab elements while managing costs. For instance, increasing the thickness of the UHPC or ECC layer typically enhances the load-bearing capacity of composite beams or plates by approximately 10% to 40%. Increasing the roughness of the interface can significantly improve the interfacial bond strength and further augment the ultimate load-bearing capacity of composite components. Moreover, the optimized design of material mix proportions and cross-sectional shapes can also contribute to enhancing the load-bearing capacity, crack resistance, and ductility of composite components. Nevertheless, challenges persist in engineering applications, such as the scarcity of long-term monitoring data on durability, fatigue performance, and creep effects. Additionally, existing design codes inadequately address the nonlinear behavior of multi-material composite structures, necessitating further refinement of design theories. Full article