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FCC-HCP phase transition plays a pivotal role in many intelligent materials, which also occurs in Pb under high pressures. However, its impacts on the spallation of polycrystalline, as well as the effects related to grain size, are still unclear. In this work, spallation behaviors of Pb polycrystals with different grain sizes under various shock loadings are investigated using the quasi-coarse-grained molecular dynamics (QCGD) method based on our recently developed response embedding atom model potential. The QCGD method is rigorously validated for applications in the metals exhibiting solid–solid phase transitions. Due to the restriction of the critical size for the phase transition nucleus, the coarsening level of the QCGD method cannot exceed two times the lattice parameter. Nevertheless, such a method enables us to explore the whole rule of the grain-size-dependence incipient spall strength. Our results suggest that the incipient spall strength exhibits a transition from the Hall–Petch to the inverse Hall–Petch relationship at about 13 nm and the spallation strength converging to that of a single crystal for grain sizes larger than 60 nm. As the grain size decreases, void nucleation becomes more prevalent than void growth, making the material better equipped to prevent the progression of damage into fractures. When the grain size is sufficiently large, voids nucleate and grow in the grain interior, making the spallation behave like in a single crystal. Interestingly, the phase transition from HCP to FCC phase enhances dislocation entanglement, leading to heterogeneous nucleation of voids in the grain interior. [ABSTRACT FROM AUTHOR]

We designed a trigonal symmetric imine-linked covalent organic framework (COF), TFPC-DAB, with control over the angularity of the building units, where a bent C2-symmetric diamine, such as 1,3-diaminobenzene (1,3-DAB or DAB), with an exo-angle of 120° was used instead of those with an exo-angle of 180°, in combination with a C3-symmetric trialdehyde, such as tri(4-formylphenoxy)cyanurate (TFPC). Its synthesis was accomplished by reacting the building units in a mixture of mesitylene/dioxane/6 M acetic acid under solvothermal conditions. The phase purity, thermal stability, and porosity of TFPC-DAB were established by various analytical techniques. Utilizing the Density Functional Tight Binding (DFTB+) simulation and Pawley refinement, the best fit of the small angle x-ray pattern was found to have an AA stacking of TFPC-DAB in the trigonal space group P3 with low refinement parameters. Such smart materials are in huge demand to detect hazardous corrosive chemicals, such as HCl and NH3. The dual features of electron deficient π-acidic triazine moiety and heteroatoms (N/O) from TFPC and electron rich phenyl units from DAB embodied in the framework enhance its luminescent property and thereby make it suitable for solvent-based HCl and NH3 sensing. The detection limits for HCl and NH3 in methanol were found to be 14 and 82 ppb, respectively. The effect of solvent polarity on the sensing studies was observed with much lower detection limits in dioxane: 2.5 and 11 ppb for HCl and NH3, respectively. A detailed theoretical calculation using density functional theory and configurational bias Monte Carlo modules was conducted for understanding interactions between the COF and HCl or NH3 analytes. [ABSTRACT FROM AUTHOR]

This review's main focus is highlighting and recognizing the significant scientific advances of smart expandable lost circulation material, i.e., shape memory polymers (SMPs) composites as loss circulation material (LCM) for drilling applications as innovative and futuristic materials. This review highlights and explains ways of producing new smart materials for LCM, which can be programmed by its SMP cycle. It briefly describes loss circulation further on loss circulation material and its classification. Only very few SMPs used as LCM, like shape memory polyurethane, thermoset shape memory polymer, shape memory epoxy, etc., either used as Grout, mixed with xanthan gum, or medium-size particles combined with base fluid, while the next section focuses on shape memory polymer as loss circulation material with the shape memory effect and programming over treating wide fractures. The last section consists of conclusion, prospects, and recommendations. [ABSTRACT FROM AUTHOR]

The treatment of vertebral compression fractures of the spinal necessitates the use of injectable bone repair materials with the adaptive modulus of elasticity. Currently, newly developed injectable self-curing materials for minimally invasive surgery are primarily categorized into calcium phosphate and calcium silicate systems, both of which exhibit excellent biocompatibility. However, calcium phosphate bone cement lacks adequate mechanical properties and the stress does not match between bone and material. Calcium silicate cement has a long curing time, low mechanical strength, and high alkalinity. These deficiencies render them inadequate for meeting clinical requirements. Therefore, we incorporated inorganic disodium phosphate, organic polyvinyl alcohol, and solid component cerium oxide into the matrix phase of tricalcium silicate bone cement to establish a ternary self-curing hydration reinforcement system and produced an organic-inorganic composite injectable bone cement. Even though the composite bone cement has a longer setting time, it exhibited high compressive strength (61.9Mpa) and fracture strain (7.88 %), demonstrating excellent mechanical properties. Furthermore, it also demonstrates good injectable properties (86 %), anti-collapse properties, good biological activity, and outstanding antibacterial properties. The composite bone cement has great potential to develop a new injectable self-curing material to replace PMMA bone cement in clinical vertebral compression fractures. [ABSTRACT FROM AUTHOR]

Based on the molecular dynamics (MD) simulation of glass transition temperature (Tg) and hydrogen bonding in the composite system of epoxy resin (Ep) and polyethylene glycol (PEG), this work developed shape memory Ep/PEG (EpP) films with controllable thermal response, recycling and reprocessing functions using melt dispersion and polymerizing‐pressing processes. EpP films with different PEG contents exhibit excellent shape memory performance, among which the shape recovery rate of EpP‐5 film can reach 92.7%, which can recover from complex structures to the initial shape. The PEG in the composite system can effectively regulate the thermal and mechanical properties of EpP, especially increasing the strain at break and reducing the Tg. Compared with EpP‐0 film. The Tg of EpP‐15 film increased by 40°C and the strain at break increased by 18.56%. Furthermore, compared with the EpP‐0 film, the recycling‐reprocessing temperature of EpP‐15 film has been reduced by 75°C. In summary, based on MD simulation, shape memory EpP films with controllable thermal response, recycling, and reprocessing functions have been successfully developed, and have shown considerable application prospects in the field of intelligent materials. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM), commonly referred to as 3D printing, has undergone significant advancements, particularly in the realm of stimuli-responsive 3D printable and programmable materials. This progress has led to the emergence of 4D printing, a fabrication technique that integrates AM capabilities with intelligent materials, introducing dynamic functionality as the fourth dimension. Among the stimuli-responsive materials, shape memory polymers have gained prominence, notably for their crucial applications in stress-absorbing components. However, the exact 3D shape morphing of 4D printed products is affected by both the 3D printing conditions as well as the stimuli activation. Hence it has been hard to precisely control the 3D shape morphing accuracy. To model and optimize the dynamic 3D evolution of the 4D printed parts, we conducted both simulation studies and real-world experiments and introduced a novel machine-learning approach extending the concept of normalizing flows. This method not only enables the process optimization of the dynamic 3D profile evolution by optimizing the process conditions during 3D printing and stimuli activation but also provides interpretability for the intermediate shape morphing process. This research contributes to a deeper understanding of the nuanced interplay between process parameters and the dynamic 3D transformation process in 4D printing. [ABSTRACT FROM AUTHOR]

In this study, by combining the polymers of polyvinylidene fluoride (PVDF) and 10,12-pentacosadinoic acid and adding the zinc oxide (ZnO) nanoparticles to their solution, three component composite nanofibers were electrospun and their thermo-chromic reversibility were investigated. Different amounts of ZnO nanoparticles based on the weight of PVDF were added to the mixture of PVDF/PDA (polydiacetylene) polymers and composite nanofibers were produced by electrospinning method. Adding ZnO to the electrospinning solvent affects nanofibers structural morphology and helps formation of beads in the electrospun nanofibers in comparison with that of PVDF/PDA sample. The crystal structure of the samples and the chemical changes in the structure of the polymers indicate that the addition of ZnO nanoparticles increases the stability of the nanofiber structure against heat and chromic change. Samples containing more than 2% ZnO with different UV irradiation times were reversible up to 140 °C. The best thermo-chromic reversibility of the PVDF/PDA/ZnO composite nanofibers could be obtained by sample containing 3% ZnO nanoparticles where the minimum irreversible temperature with an UV irradiation time of 5 min for this sample is 170 °C. [ABSTRACT FROM AUTHOR]

The TMS Board of Directors recently approved professional membership for a diverse group of new members from countries like the United States, Pakistan, Canada, and Zimbabwe, representing institutions ranging from universities to technology companies. This decision underscores TMS's commitment to inclusivity and collaboration within the minerals, metals, and materials science field. The list of new members welcomed in May and August 2024 includes individuals from various countries and institutions, showcasing a global community of researchers and professionals working together in fields like materials science and engineering. The document highlights international collaboration and knowledge exchange among researchers and professionals from countries such as the United States, Japan, Germany, and South Korea, emphasizing the importance of global partnerships in advancing scientific research efforts. [Extracted from the article]

One of the defining properties of self-healing materials is their capacity to spontaneously and independently repair damage, i.e. without any intervention from an outside source. This is one of the ways in which these materials are distinguished from others. In comparison to polymers, designing and implementing a self-healing mechanism in metals is a challenging task due to the inherent high melting temperatures and low atomic diffusivities of metals. This makes it difficult to develop and execute a self-healing mechanism in metals. The materials that are frequently used in engineering, automobile, aviation, and deep ocean oil well applications are subjected to a significant amount of pressure during the manufacturing process. The forms of material damage that are typically encountered in these applications include plastic flow instability, compromise to the automobile structural integrity, fatigue, and shape deformation. As a result of this, the industry is on the hunt for composite materials that not only have a high strength but also excel in their mechanical and tribological attributes. This article gives a summary and analysis of the numerous research efforts that have been done to generate self-healing metals and the applications that can make use of them. In conclusion, we talk about a few potential directions that future studies into the self-healing characteristics of metals could take. [ABSTRACT FROM AUTHOR]

This work presents a hybrid multidirectional mechanical energy harvester to enhance the performance of a cantilever-based harvester when subjected to multidirectional excitations. The multidirectional capabilities are achieved by employing a pendulum structure. Hybrid transduction is provided by combining a piezoelectric element and an electromagnetic transducer. A reduced-order model is presented based on the electromechanical Lagrangian formulation, and numerical analyses are performed to characterize the system behavior. A comparison based on energy harvesting performance is established among the novel multidirectional hybrid energy harvester (MHEH), the classical piezoelectric harvester (CPEH), and a multidirectional piezoelectric harvester (MPEH). Results show that the addition of the pendulum alone indeed provides multidirectional capabilities, but the overall performance can be reduced in some scenarios since it works as an energy absorber. This limitation is overcome by the hybridization strategy of the MHEH, by incorporating an electromagnetic transducer into the pendulum support. Overall, a significant improvement is achieved in all scenarios by utilizing the hybrid system. [ABSTRACT FROM AUTHOR]

We study the emergence of chemical intelligence in proteinoid–ZnO nanocomposites through their interaction with visible light. When these novel materials are exposed to light, they display electrical spiking behaviour that is similar to the action potentials of neurons. We examine the influence of various light conditions, such as wavelength, intensity, and duration, on the photo-response of these nanocomposites. The results indicate that higher light intensity and longer duration are associated with increased frequency and amplitude of voltage spikes. Furthermore, blue light is more effective than red light in this regard. This light-dependent behaviour indicates a form of chemical intelligence, in which the material learns and responds to external stimuli. The results of our research emphasise the potential of proteinoid–ZnO nanocomposites to develop bio-inspired, light-sensitive systems, which can lead to advancements in areas such as photocatalysis, unconventional computing, and adaptive materials. This study enhances the understanding of chemical intelligence and how it is demonstrated in synthetic nanomaterials. [ABSTRACT FROM AUTHOR]

Dynamic covalent bonds endow liquid crystal elastomers (LCEs) with network rearrangeability, facilitating the fixation of mesogen alignment induced by external forces and enabling reversible actuation. In comparison, the bond exchange of supramolecular interactions is typically too significant to stably maintain the programmed alignment, particularly under intensified external stimuli. Nevertheless, remaking and recycling of supramolecular interaction‐based polymer networks are more accessible than those based on dynamic covalent bonds, as the latter are difficult to completely dissociate. Thus, preparing an LCE that possesses both supramolecular‐like exchangeability and covalent bond‐level stability remains a significant challenge. In this work, we addressed this issue by employing metal‐ligand bonds as the crosslinking points of LCE networks. As such, mesogen alignment can be repeatedly encoded through metal‐ligand bond exchange and stably maintained after programming, since the bond exchange rate is sufficiently slow when the programming and actuation temperatures are below the bond dissociation temperature. More importantly, the metal‐ligand bonds can be completely dissociated at high temperatures, allowing the LCE network to be dissolved in a solvent and reshaped into desired geometries via solution casting. Building on these properties, our LCEs can be fabricated into versatile actuators, such as reversible folding origami, artificial muscles, and soft robotics. [ABSTRACT FROM AUTHOR]

Achieving structural reconfiguration of supramolecular bottlebrush block copolymers toward topological engineering is of particular interest but challenging. Here, we address the creation of supramolecular architectures to discover how assembled topology influences the structured aggregates, combining hydrogen‐bonded (H‐bonded) bottlebrush block copolymers and electrostatic interaction induced polymer/inorganic eutectics. We first design H‐bonding linear‐brush block copolymer P(NBDAP‐co‐NBC)‐b‐P(NBPEO), bearing linear block P(NBDAP‐co‐NBC) (poly(norbornene‐terminated diaminopyridine‐co‐norbornene‐terminated hexane)) with pendant H‐bonding DAP (diaminopyridine) motifs, and PEO (poly(ethylene oxide)) densely grafted P(NBPEO) brush block. Thanks to H‐bonding association between DAP and thymine (Thy), incorporation of Thy‐functionalized polystyrene (Thy‐PS65) enables solution self‐assembly and formation of H‐bonded bottlebrush block copolymers, generating augmented nanospheres with increasing Thy‐PS65 amount. Noteworthy that integration of inorganic cluster silicotungstic acid (STA) to P(NBC‐co‐NBDAP)‐b‐P(NBPEO), endows the formation of PEO/STA eutectic core. Therefore, co‐crystallization‐assistant self‐assembly at the interfaces of polymeric, inorganic and supramolecular chemistry is realized, reflecting multi‐stage morphology transformation from hexagonal platelets, needle‐like, curved rod‐like micelles, finally to end‐to‐end closed rings, by gradually increasing Thy‐PS65 while fixing STA content. Interestingly, such solution self‐assembly to co‐crystallization‐assistant self‐assembly strategy not only endows unique nanostructure transition, also induce in‐to‐out reconfiguration of PS domains. These findings clearly provide unique methodology towards programmable fabrication of geometrical objects promising in smart materials. [ABSTRACT FROM AUTHOR]

The MOF‐guest relationship is broken down in elementary phases, descriptors, and parameters. These descriptors and parameters allow precise descriptions of processes, whether they occur at the point when the guest enters the MOF, during the stay, or at the point of exiting. Description of these three phases is possible according to the location of the guest inside the MOF, the activity between MOF and guest, whether stimuli can be used, and whether a selective action can be exercised. The vocabulary provided herein can be useful to better formulate requirements when designing host‐guest interactions in, and building new classes of, intelligent materials. [ABSTRACT FROM AUTHOR]

Highlights Polypropylene composites with different contents of zinc‐ammonium salts (3, 5 and 7 wt%) and nanocellulose (1 wt%) after enzymatic bioconversion were characterized by structural, dispersion‐morphological, thermal, antimicrobial and mechanical analysis. It was shown that the use of a newly synthesized salt significantly affected the formation of the supermolecular structure of the polymer matrix and increased the nucleation activity, thermostability and flexibility of the composite materials. Moreover, the addition of the inorganic filler allowed to obtain composites with very good antimicrobial properties against Staphylococcus aureus, Escherichia coli and Candida albicans. An interesting relationship between the degree of filler dispersion in the polymer matrix and the formation of polymorphic varieties was elucidated in the study, which contributes to the improvement of final performance characteristics of composite materials. It is noteworthy that a hybrid filler in the form of nanometric cellulose and a biocidal additive containing zinc‐ammonium complex salt was used for the first time. Research has shown that such polymer composites can find application during the manufacture of smart packaging materials with enhanced barrier properties against oxygen and water vapor as well as improved biocidal characteristics, which will notably extend food storage time. At the same time, the presented process of obtaining the innovative composite materials is an excellent example of sustainable technologies for the design of antimicrobial treatments, while guaranteeing the possibility of further processing of these composite materials through material recycling. Zinc‐ammonium complex with antimicrobial properties was obtained The strength properties and thermal stability of the composites were improved Degree of filler dispersion in polymer affects formation of polymorphic varieties The composites can be applied in the production of smart packaging materials [ABSTRACT FROM AUTHOR]

Synthetic duplexes with high stabilities have promising potential for mimicking biomolecular functions and developing supramolecular smart materials. Herein, we describe the synthesis and stimuli‐responsive properties of molecular duplexes derived from indolocarbazole–pyridine (I−P) oligomers. These duplexes adopt nonclassical helical structures, stabilized by I−P hydrogen‐bonding pairs in anhydrous chlorinated solvents. Notably, the longest duplex 62 (11‐mer)2 displays remarkable stability, forming twenty hydrogen bonds; its exchange energy barrier was determined to be ΔG≠=22.0 kcal ⋅ mol−1 at 75 °C in anhydrous (CDCl2)2. Upon the addition of water, a hydrated duplex 62 (11‐mer)2⊃10H2O was formed, with one water molecule inserted between each I−P hydrogen‐bonding pair. The Hill coefficient (n) for this process is 6.1, demonstrating extremely positive cooperativity. Conversely, the hydrated duplex 62 (11‐mer)2⊃10H2O was completely converted into the original anhydrous duplex 62 (11‐mer)2 when the temperature was increased. Interconversion between these two distinct duplexes can be repeatedly carried out by varying the temperature. Furthermore, reversible switching between hetero‐duplexes and homo‐duplexes was also demonstrated by controlling the temperature, with concomitant changes in the characteristic emission signals. [ABSTRACT FROM AUTHOR]

Maximizing materials utilization efficiency via enhancing their reconfigurability and multifunctionality offers a promising avenue in addressing the global challenges in sustainability. To this end, significant efforts have been made in developing reconfigurable multifunctional smart materials, which can exhibit remarkable behaviors such as morphing and self-healing. However, the difficulty in efficiently manipulating and controlling matter at the building block level with manageable cost and complexity, which is crucial to achieving superior responsiveness to environmental clues and stimuli, has significantly hindered the further development of such smart materials. Here we introduce a concept of Robo-Matter, which can be activated and controlled through external information exchange at the building block level, to enable a high-level of controllability, mutability and versatility for reconfigurable multifunctional smart materials. Using specially designed micro-robot building blocks with symmetry-breaking active motion modes, tunable anisotropic interactions, and interactive coupling with a programmable spatial-temporal dynamic light field, we demonstrate an emergent Robot-Matter duality, which enables a spectrum of desirable behaviors spanning from matter-like properties such as ultra-fast self-assembly and adaptivity, to robot-like properties including active force output, smart healing, smart morphing and infiltration. Our work demonstrates a promising direction for designing next-generation smart materials and large-scale robotic swarms. The authors introduce the concepts of Robo-Matter and Robot-Matter duality, using magnetic spinner micro-robots. A wide range of functionalities and applications beyond the capability of both traditional inert and active materials is enabled. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive block copolymer nanoparticles (NPs) have received close attention in recent years owing to their tremendous application potential in smart materials. Azobenzene‐containing NPs are widely studied due to the advantages of light as a stimulus and fast reversible trans–cis isomerization of azobenzene chromophores. However, the inefficient preparation process and difficult reversible transformation of morphologies limit their development. Herein it is demonstrated that the light‐triggered reversible swelling behavior of wormlike NPs with high azobenzene content could be realized via confined deformation. These worms are prepared in large quantities via polymerization‐induced self‐assembly based on the copolymerization of 11‐(4‐(4‐butylphenylazo)phenoxy)undecyl methacrylate (MAAz) and N‐(methacryloxy)succinimide (NMAS) monomers. Upon UV/visible light irradiation, the reversible deformation of worms is achieved when the feed molar ratio of NMAS/MAAz is relatively high or via crosslinking using diamines, which leads to the reduction of the photoisomerization efficiency. The diameter variation of the worms is influenced by the amount and types of crosslinkers. Moreover, the scalability of this strategy is further proved by the fabrication of photo‐ and reductant‐responsive crosslinked worms. It is expected that this study not only provides a new route to affording reversible photoresponsive NPs but also offers a unique insight into the reversible photodeformation mechanism of azobenzene‐containing NPs. [ABSTRACT FROM AUTHOR]

Smart materials react to external triggers by changing size, color, mechanical properties, or permeability. The next generation of smart materials will be able to not only recognize and react to external triggers but also to their dynamics. The only existing example of such a material is heating rate‐sensitive polymorphous cross‐linked syndiotactic polypropylene. This study presents a new principle of a heating rate‐sensitive material on the example of cross‐linked and fully amorphous quenchable semi‐crystalline polyethylene terephthalate (x‐PET). The x‐PET is stretched to high elongation above its melting temperature and constrained quenched to a fully amorphous state. Then the polymer is heated to 120–170 °C with different heating rates. Due to its heating‐rate sensitivity, x‐PET shrinks to different stabilized lengths dependent on the heating rate. The new length can be used to read out the heating rate and to specifically answer to this by mechanically switching a process. Detailed analytics of this process reveal that amorphous stretched x‐PET is starting the retraction above Tg and simultaneously stopping it by crystallization. The different rates of these processes result in the heating rate sensitivity of x‐PET. [ABSTRACT FROM AUTHOR]

Thermochromic smart windows have emerged as a focal point in energy research. In this study, a novel approach is introduced for developing thermoresponsive materials for smart windows, utilizing microscopic agglomeration of molecules to regulate incident light. The groundbreaking material, β‐CD‐Val‐IBAm4, is constructed by grafting four isobutylated valines onto natural β‐cyclodextrins. This material exhibits a unique "hand‐in‐hand" effect, resulting from the interaction of isobutylated valine side chains, which leads to molecular aggregation and reduced light transmission at elevated temperatures. The hydration–dehydration process is related to molecular aggregation rather than crosslinking, ensuring the structural integrity and uniformity of the smart windows. Molecular dynamics simulations and 2D NOESY confirm the thermal response mechanism of β‐CD‐Val‐IBAm4. When dissolve in a glycerol‐water binary solvent system, the material forms a thermochromic liquid with outstanding optical performance (ΔTsol of 1 mm liquid can reach 69.8%) and long‐term stability. This innovative approach opens new avenues for the advancement of next‐generation smart window technologies. [ABSTRACT FROM AUTHOR]

Natural materials possess inherent multilength‐scale structures, showcasing outstanding mechanical properties such as strain‐stiffening, high damping, and shape‐memory features under ambient conditions. Such integrated properties are highly desirable for advanced materials in biomedical devices and soft robots but remain challenging in synthetic materials. Herein, a novel strategy of sequential ion treatment is employed to introduce micro/nanoscale‐ordered structures and molecular‐scale stimulus responses into hydrogel‐derived self‐assembly fibers under ambient conditions. The treated fibers exhibit strain‐stiffening properties with a high toughness of 257 MJ m−3 and 73% damping capacity comparable to spider silk. Owing to their cross‐linking network and reversible secondary structure, those fibers exhibit outstanding water‐stability, wet stretchability, and hydration‐responsive shape‐memory performance, with ultimate elongation of 407%, shape‐fixity ratio of 94%, and shape‐recovery rate of 97%. This work furthers the green fabrication of smart materials with multifunction and presents promising applications in diverse fields, including biomimetics and biomedicine. [ABSTRACT FROM AUTHOR]

Smart electrospun hybrid nanofibers represent a cutting‐edge class of functional nanostructured materials with unique collective properties. This review aims to provide a comprehensive overview of the applications of smart electrospun hybrid nanofibers in the fields of energy, catalysis, and biomedicine. Electrospinning is a powerful tool to fabricate different types of nanofibers’ morphologies with precise control over structure and compositions. Through the incorporation of various functional components, such as nanoparticles, nanomoieties, and biomolecules, into the (co)polymer matrix, nanofibers can be tailored into smart hybrid materials exhibiting responsiveness to external stimuli such as temperature, pH, or light among others. Herein recent advancements in fabrication strategies for electrospun smart hybrid nanofibers are discussed, focusing on different electrospinning tools aimed at tailoring and developing smart hybrid nanofibers. These strategies include surface functionalization, doping, and templating, which enable fine‐tuning of mechanical strength, conductivity, and biocompatibility. The review explores the challenges and recent progress in the development of smart hybrid nanofibers. Issues such as scalability, reproducibility, biocompatibility, and environmental sustainability are identified as key for improvement. Furthermore, the applications of smart nanofibers in biomedicine, environment, energy storage, and smart textiles underscore their potential to address the challenges in development of nanostructured materials for emerging technologies. [ABSTRACT FROM AUTHOR]

4D printing magneto‐responsive shape memory polymers (SMPs) using biodegradable nanocomposites can overcome their low toughness and thermal resistance, and produce smart materials that can be controlled remotely without contact. This study presented the development of 3D/4D printable nanocomposites based on poly (lactic acid) (PLA)‐poly (butylene adipate‐co‐terephthalate) (PBAT) blends and magnetite (Fe3O4) nanoparticles. The nanocomposites are prepared by melt mixing PLA‐PBAT blends with different Fe3O4 contents (10, 15, and 20 wt%) and extruded into granules for material extrusion 3D printing. The morphology, dynamic mechanical thermal analysis (DMTA), mechanical properties, and shape memory behavior of the nanocomposites are investigated. The results indicated that the Fe3O4 nanoparticles are preferentially distributed in the PBAT phases, enhancing the storage modulus, thermal stability, strength, elongation, toughness, shape fixity, and recovery of the nanocomposites. The optimal Fe3O4 loading is found to be 10 wt%, as higher loadings led to nanoparticle agglomeration and reduced performance. The nanocomposites also exhibited fast shape memory response under thermal and magnetic activation due to the presence of Fe3O4 nanoparticles. The 3D/4D printable nanocomposites demonstrated multifunctional multi‐trigger shape‐memory capabilities and potential applications in contactless and safe actuation. [ABSTRACT FROM AUTHOR]

Fabricating photonic crystals (PCs) with dynamic multi‐stimuli‐responsive structural colors, recordable colors, and self‐healable properties is significant for their emerging applications, yet remains a big challenge. Here, an all‐in‐one multifunctional PC (MFPC) film with outstanding mechanochromic, thermochromic, solvatochromic, color/shape‐recordable, self‐healable, and adhesive functions is designed and prepared by simply non‐close‐assembling silica particles into the unique 2‐[[(Butylamino)carbonyl]oxy]ethyl acrylate (BCOEA) followed by photopolymerization. The success is mainly due to the rational combination of non‐close‐packing structures and BCOEA's characteristics, including its urethane groups with numerous sacrificial hydrogen bonds, temperature‐dependent refractive index, swellable and deformable polymer network, as well as low glass‐transition temperature. The MFPC's hue and color saturation can be reversibly and dynamically modulated by strain/pressure/solvents and temperature, respectively, thereby realizing visually and spectrally sensing these stimuli. More interestingly, the color‐responsiveness combined with other functions endows MFPCs with fascinating emerging applications, including multilayer optical filters, inkless printing, reconfigurable multicolor patterns, stretching‐based anti‐counterfeiting, etc. This work offers a new perspective for designing next‐generation smart photonic materials and will facilitate their all‐round applications. [ABSTRACT FROM AUTHOR]

Dynamic response room temperature phosphorescence (RTP) is a hot topic in smart materials research due to its unique RTP‐response characteristics under external stimuli. However, its precisely control are currently challenging. Here, an alkyl chain‐induced lattice‐softening strategy is proposed to precisely regulate photoactivated dynamic RTP (PDRTP). By adjusting the alkyl chain flexibility of hybrid metal halide matrices, oxygen permeability can be adjusted, thereby achieving finely manipulate of the photoactivation equilibrium time, RTP lifetime, and RTP wavelength of the resulted host–guest doped materials within the ranges of 10–600 s, 0.05‐1.62 s, and 405–595 nm, respectively. It is also demonstrated the potential application of the PDRTP materials in afterglow oxygen sensing and multi‐level information encryption. This study not only proposes an effective method for regulating the photosensitivity of PDRTP materials, but also points out a new direction for exploring gas permeability in dense‐packed crystalline materials. [ABSTRACT FROM AUTHOR]

People are exploring the potential application of 3D printing in food, biomedicine and environment, but it is urgent to find suitable bio-ink. Bio-ink compounded with starch and hydrocolloid can not only improve the rheology, structure and printability of starch-based edible bio-ink, but also endow it with other functional characteristics, so that it can be applied to food, biomedicine and even the environment, and meet the strategic needs of national health, green and sustainable development. In this paper, hydrocolloids are reviewed as potential means to regulate the physicochemical properties of starch, which endows it with good printability and presents excellent printing products. The specific applications of the bio-ink in the fields of food, biomedicine and environment in hypoglycemic, lipid-lowering, swallowable food, delivery, intelligent materials, and bio-sensor are also discussed. Then, the challenges and future development trends of realizing large-scale application are prospected. Proper physicochemical properties of starch-hydrocolloid are positively correlated with printability. The presentation of excellent printability has realized the application in different fields, not only satisfies most people, but also create benefits for some specific people. This review is expected to provide some theoretical guidance for the further development of 3D printing technology and its large-scale application. [ABSTRACT FROM AUTHOR]

Smart polymeric coatings play a crucial role in protecting steel surfaces from corrosion and wear. One of progressive smart behavior is self-healing behavior especially in self-healing epoxy coatings. Creating or improving the second smart behavior is known as a new trend for these smart materials. This study aims to investigate the effects of ZrO 2 nanoparticles on the self-lubricating behavior as the second smart behavior of the linseed oil-loaded microcapsule/epoxy composite coatings. To do so, the in-situ polymerization method was used for the synthesis of linseed oil-loaded microcapsule. Results showed that the average size of prepared linseed oil-loaded microcapsules was 563 nm. The composite coatings were prepared by different content of ZrO 2 nanoparticles (0, 3, 6, 9, 12, and 15 wt%) and constant content of linseed oil-loaded microcapsules (5 wt%). The tribological performance of samples was studied using pin-on-disk test. The worn surface of the samples was also studied using field emission scanning electron microscope (FESEM) images. Results proved that the frictional coefficient and wear rate of the samples were significantly decreased by increasing the concentrations of the ZrO 2 nanoparticles up to 9 wt%. The lowest friction coefficient and wear rate values of 0.085 and 0.142 × 10−6 mm3/Nm were obtained for 5 wt% linseed oil-loaded microcapsules/epoxy with 9 wt% ZrO 2 which were about 82 % and 88 % lower than those of pure epoxy coating. [ABSTRACT FROM AUTHOR]

The rapid development of wireless technology has heightened the requirement for antenna performance. Traditional antennas, characterized by their static performance, are no longer sufficient to accommodate the dynamic requirements of modern wireless systems. The advent of reconfigurable antennas has opened new horizons for unleashing the full potential of wireless communication systems. These antennas are versatile and can switch various performance modes in a simple yet ingenious structure. Based on the cutting‐edge research, this paper deeply explores their core design principles, the latest breakthroughs, and the ingenious methods. Through an in‐depth analysis of a multitude of reconfigurable antenna design cases, existing design methods are categorized into four categories: electronic and optical switches, structural physical change, smart materials, and bistable composites. Each category is subjected to a meticulous dissection, revealing the underlying design mechanisms, highlighting innovativeness, and discussing both the strengths and limitations. Furthermore, by conducting a comprehensive comparative analysis, this paper concludes the forthcoming challenges and prospective trajectories for this research domain. Therefore, this paper can serve as a valuable reference for researchers seeking to deepen their understanding and application of various reconfiguration methods in the design of reconfigurable antennas, guiding them toward the forefront of antenna technology innovation. [ABSTRACT FROM AUTHOR]

Triply periodic minimal surface (TPMS) structures with excellent properties of stable energy absorption, light weight, and high specific strength could potentially spark immense interest for novel and programmable functions by combining smart materials, e.g. shape memory polymers (SMPs). This work proposes TPMS lattices with hybrid configurations and materials that are composed of viscoelastic and shape-memory materials with the aim to bring temperature-dependent mechanical properties and additional dissipation mechanisms. Different configurations and diverse materials of polylactic acid (PLA), fiber-reinforced PLA, and polydimethylsiloxane (PDMS) are induced, generating five types of TPMS lattices, including (Schoen’s I-WP) IWP uniform lattice, IWP lattice with density gradient, hybrid configurations, hybrid materials, and filled PDMS, which are fabricated by 3D printing. The fracture morphologies and the distribution of carbon fibers are demonstrated via scanning electron microscopy with a focus on the influence of carbon fiber on shape-memory and mechanical properties. Shape recovery tests are conducted, which proves good shape memory properties and reusable capability of TPMS lattice. The combined methods of experiments and numerical simulation are adopted to evaluate mechanical properties, which presents multi-stage energy absorption ability and tunable vibration isolation performances associated with temperature and hybridization designs. This work can promote extensive research and provide substantial opportunities for TPMS lattices in the development of functional applications. [ABSTRACT FROM AUTHOR]

Achieving smart single‐phase materials with switchable thermal expansion is challenging, as most materials undergo volumetric thermal expansion upon heating. Here, it is reported that the porphyrin‐based metal‐organic frameworks (MOFs) can show switchable thermal expansion, ranging from negative to positive, by controlling the central metal ions. The pristine compound, along with those functionalized with Ni2+ or FePz2+ (Pz stands for pyrazine) show pronounced negative thermal expansion (NTE), while the FeCl2+ functionalized analogue shows moderate positive thermal expansion (PTE). Detailed molecular dynamic simulations shed light on that the NTE originates from the collective low‐frequency phonon modes, concerning the in‐plane/out‐of‐plane rotations and trampoline‐like vibrations of porphyrin groups. The introduction of FeCl2+ can disrupt the planarity of the porphyrin groups, stiffening the NTE related phonons, thus leading to the PTE. In contrast, the introduction of Ni2+ or FePz2+ groups can maintain the planar structure, thereby preserving the NTE. This study not only provides a molecular‐level understanding of thermal expansion but also opens a pathway for tailoring thermal expansion through post‐synthesis modification of molecular structures. [ABSTRACT FROM AUTHOR]

Nature has evolved a myriad of dedicate‐designed structures that assist in prey capture. Spiders employ their web structures for vibrational sensing and prey capture, analogous to a component of a neurosensory system. Here, we propose a spider web‐inspired sensor with integrated energy‐absorption and force perception capabilities by 3D printing. The conductive carbon black/TPU composite made from TPU granules and carbon black particles are employed for 3D printing. We analyze the underlying sensing mechanism of conductive CB/TPU composites stemming from the enhanced dispersion of the CB particles. Through 3D printing method, we are allowed to regulate the structure's form, filling density, arrangement, and printing path to tailor the static mechanical properties, initial resistance, and force sensitivity of the spider‐web inspired structure. The static mechanical model for single silk of the spider‐web inspired structure is constructed. We explore the energy absorption capability of spider‐web inspired structures with different structural parameters, and demonstrate its impact perceiving characteristics at different falling height. Additionally, we assembled a circuit to visually reflect the falling height of the impacting ball through the brightness of the LED light. This study provides insights to endowing structural materials with intelligent characteristics, contributing to their practical applications in the fields of biomedical, soft robotics, and artificial skin, etc. Highlights: A spider web‐inspired sensor is 3D printed with CB/TPU composites.The sensor has integrated force perception and energy‐absorption capabilities.The sensitivity capabilities can be regulated by parameter design.The mechanical model of the bioinspired structure is constructed.Its impact perceiving characteristics are demonstrated by two applications. [ABSTRACT FROM AUTHOR]

Soft actuators are constituted by a type of intelligent materials, and they can generate reversible mechanical motions under external stimuli. They usually achieve continuous actuation by manual turning on or off the power supply, which significantly increases the operation complexity. In contrast, self-oscillating actuators can achieve autonomous motions under constant stimuli, and have recently attained great advancements, as well as promoted the development of autonomous soft robotics. In this review, the latest achievements of soft oscillators are summarized. First, the self-oscillating mechanisms mainly including oscillating chemical reactions and self-shadowing-induced mechanical negative feedback loops are discussed. The oscillators constructed with various materials and configurations, driven by different stimuli and applied in different fields are then presented in detail. Finally, the difficulties and hopes of oscillators are presented. Overall, self-oscillating actuators are in the stage of vigorous development, and we believe that in the future, they will be used in various fields and make many scenarios more intelligent and autonomous. [ABSTRACT FROM AUTHOR]

Robotic grasping is a common operation scenario in industry and agriculture, in which the force sensing function is a significant factor to achieve reliable grasping. Existing force sensing methods of flexible grippers require intelligent materials or force sensors embedded in the flexible gripper, which causes such problems of higher manufacturing requirements and contact surface properties changing. In this paper, a novel rope-driven force sensing flexible gripper is designed based on the fin-shaped gripper structure, which can realize the grasping sensing functions of contact nodes and contact forces without the need for force sensors. Firstly, the rope-driven force sensing flexible gripper is designed, including the driving unit, the transmission part, the gripper unit, and the force sensing unit. The force sensing unit and the gripper unit are connected by rope, and the prototype of the rope-driven force sensing flexible gripper is completed. Secondly, a force sensing algorithm and control system based on finite element method and grasping geometric relationship are designed to realize the rope-driven force sensing flexible gripper grasping control and sensor data acquisition and processing. Finally, the experimental system of the rope-driven force sensing flexible gripper is built, and the grasping experimental tests of objects with different diameters and different contact nodes are carried out to verify the force sensing function of the rope-driven force sensing flexible gripper. The force sensing flexible gripper designed in this paper can provide a new idea for the design and force sensing method of intelligent robotic grasping system in robotic teaching, scientific research, and industrial applications. [ABSTRACT FROM AUTHOR]

High electrical conductivity, along with high piezoresistive sensitivity and stretchability, are crucial for designing and developing nanocomposite strain sensors for damage sensing and on-line structural health monitoring of smart carbon fiber-reinforced polymer (CFRP) composites. In this study, the influence of the geometric features and loadings of carbon-based nanomaterials, including reduced graphene oxide (rGO) or carbon nanofibers (CNFs), on the tunable strain-sensing capabilities of epoxy-based nanocomposites was investigated. This work revealed distinct strain-sensing behavior and sensitivities (gauge factor, GF) depending on both factors. The highest GF values were attained with 0.13 wt.% of rGO at various strains. The stability and reproducibility of the most promising self-sensing nanocomposites were also evaluated through ten stretching/relaxing cycles, and a distinct behavior was observed. While the deformation of the conductive network formed by rGO proved to be predominantly elastic and reversible, nanocomposite sensors containing 0.714 wt.% of CNFs showed that new conductive pathways were established between neighboring CNFs. Based on the best results, formulations were selected for the manufacturing of pre-impregnated materials and related smart CFRP composites. Digital image correlation was synchronized with electrical resistance variation to study the strain-sensing capabilities of modified CFRP composites (at 90° orientation). Promising results were achieved through the incorporation of CNFs since they are able to form new conductive pathways and penetrate between micrometer-sized fibers. [ABSTRACT FROM AUTHOR]

This review focuses on advancements in polymer science as it relates to three-dimensional (3D) and four-dimensional (4D) printing technologies, with a specific emphasis on applications in the biomedical field. While acknowledging the breadth of 3D and 4D printing applications, this paper concentrates on the use of polymers in creating biomedical devices and the challenges associated with their implementation. It explores integrative modeling and experimental insights driving innovations in these fields, focusing on sustainable manufacturing with biodegradable polymers, a comparative analysis of 3D and 4D printing techniques, and applications in biomedical devices. Additionally, the review examines the materials used in both 3D and 4D printing, offering a detailed comparison of their properties and applications. By highlighting the transformative potential of these technologies in various industrial and medical applications, the paper underscores the importance of continued research and development. The scope of this review also includes an overview of future research directions to address current challenges, enhance material capabilities, and explore practical applications. [ABSTRACT FROM AUTHOR]

Flexible grippers are a promising and pivotal technology for robotic grasping and manipulation tasks. Remarkably, magnetorheological (MR) materials, recognized as intelligent materials with exceptional performance, are extensively employed in flexible grippers. This review aims to provide an overview of flexible robotic grippers and highlight the application of MR materials within them, thereby fostering research and development in this field. This work begins by introducing various common types of flexible grippers, including shape memory alloys (SMAs), pneumatic flexible grippers, and dielectric elastomers, illustrating their distinctive characteristics and application domains. Additionally, it explores the development and prospects of magnetorheological materials, recognizing their significant contributions to the field. Subsequently, MR flexible grippers are categorized into three types: those with viscosity/stiffness variation capabilities, magnetic actuation systems, and adhesion mechanisms. Each category is comprehensively analyzed, specifying its unique features, advantages, and current cutting-edge applications. By undertaking an in-depth examination of diverse flexible robotic gripper types and the characteristics and application scenarios of MR materials, this paper offers a valuable reference for fellow researchers. As a result, it facilitates further advancements in this field and contributes to the provision of efficient gripping solutions for industrial automation. [ABSTRACT FROM AUTHOR]

Due to their advantageous characteristics, shape memory alloys (SMAs) are prominent representatives in smart materials. They can be used in application fields such as soft robotics, biomimetics, and medicine. Within this work, a fiber–elastomer composite with integrated SMA wire is developed and investigated. Bending and torsion occur when the SMA is activated because of the anisotropic structure of the textile. The metrological challenge in characterizing actuators that perform both bending and torsion lies in the large active deformation of the composite and the associated difficulties in fully imaging and analyzing this with optical measurement methods. In this work, a multi-sensor camera system with up to four pairs of cameras connected in parallel is used. The structure to be characterized is recorded from all sides to evaluate the movement in three-dimensional space. The energy input and the time required for an even deflection of the actuator are investigated experimentally. Here, the activation parameters for the practical energy input required for long life with good deflection, i.e., good efficiency, were analyzed. Different parameters and times are considered to minimize the energy input and, thus, to prevent possible overheating and damage to the wire. Thermography is used to evaluate the heating of the SMA wire at different actuation times over a defined time. [ABSTRACT FROM AUTHOR]

Textile-reinforced cementitious composites have great potential to offer novel design opportunities for thin-section structures thanks to their superior material capabilities. In this work, new cementitious composites with novel reinforcement configurations are developed, which have superior mechanical properties. The cementitious composites contain inclined through-the-thickness reinforcements, and their enhanced performance on thin-section material hardening under flexural loading is demonstrated. Furthermore, a new practical FE modeling approach is proposed that involves the combined use of multiple cohesive regions and 1D reinforcement elements that pass through these regions with a bilinear material law. This approach provides a new computationally efficient modelling framework whereby reinforcement pull-out during hardening is readily captured without resorting to computationally demanding interface laws between the reinforcement and the cementititous matrix. The model can model enhanced hardening of new configurations and provides comparable results with the experimental findings. The model can be used in the modelling and design of novel cementitious composites with engineered reinforcement configurations. Overall, this study aims to open up new avenues for the smart material design of cementitious composites with novel structural reinforcements. [ABSTRACT FROM AUTHOR]

Polymeric composites are prone to undergoing damage, such as microcracks, during their operation, which can ultimately lead to catastrophic failure. To contradict such a problem, efforts have been carried out, by the scientific community, towards developing self-healing composites that, by mimicking biological systems, can autonomously and prematurely repair flaws, extending the durability and improving the security of materials. The present review explores the progress made in this area, focusing on extrinsic self-healing methods, as these can be employed to a variety of materials. Reservoir-based techniques, which resort to capsules, hollow fibers or microvascular networks, and thermoplastic-based ones are overviewed, prioritizing innovative approaches made in recent years. At last, promising practical applications for self-healing composites are highlighted and future challenges and opportunities are pointed out. [ABSTRACT FROM AUTHOR]

Additive manufacturing technology has been applied to the textile field because of its multifunctionality low cost and high efficiency. The advantage of this technology in the textile field is that it breaks through the complexity of traditional manufacturing technology in terms of material scale structure and function. With the progress of printing equipment and the research and development of new intelligent materials the additive manufacturing of textiles is gradually developing from 3D printing to 4D printing. The application of 3D-printed textiles is mainly divided into two categories. The first category is the integration of textile preparation and molding and the second category is the integration of textile materials and structures. 4D printing is also an advanced manufacturing technology that has been applied in the textile field. Different from 3D printing 4D printing combines textile design with smart materials and the printed microstructures can be changed in size shape or function according to the pre-designed trajectory at a specific time and under activation conditions. There are various types of 3D printing technologies but the basic characteristics of textiles limit the types of additive manufacturing technologies that can be used for manufacturing. In addition while 4D printing technologies primarily use 3D printing equipment the functional properties of the materials to be printed and the required driveability of the printed structures also limit the types of technologies available for textile additive manufacturing. As a result the main types of additive manufacturing forming methods that are more commonly used for 3D printing and 4D printing of textiles are material extrusion forming light-curing forming jet forming and powder bed melt forming which cover a wide range of material forms including solids filaments or particles liquids photosensitive resins or adhesive materials and powders metal or plastic powders . Each forming method and material type has its own unique application scenarios and advantages for different types of additively manufactured textiles. Based on the basic principles and main features of additive manufacturing the process of textile additive manufacturing can be divided into seven key steps including creation of the CAD model processing model pre-printing preparation printing model taking out the printed fabricated part post-processing and application. The design and production ideas of additive manufacturing emphasize taking full advantage of the unique benefits of additive manufacturing at the design stage while also considering post-production processing and the overall life cycle of the product. The discussion on design and fabrication ideas for textile additive manufacturing focuses on four main directions textile fibers flexible textiles hybrid textile structures and bionic textiles. The development of textile additive manufacturing from 3D printing to 4D printing represents a significant advancement in the field of smart manufacturing and reflects the gradual expansion of traditional 3Dprinted static textiles to 4D-printed smart textiles. It introduces a new level of functionality adaptability and customization and is expected to disrupt traditional textile design textile manufacturing and interaction with textiles. [ABSTRACT FROM AUTHOR]

Monolayer atomic crystals show significant advantages in improving charge storage kinetics for electrode materials. While notable progress is made, challenges remain in producing nanocrystals with desirable configurations, dimensions, and crystallographic properties. Here, 1D single‐crystal nanobelts assembled from monolayer sodium titanate nanobelts are reported with highly exposed active sites as anode materials for sodium‐ion batteries (SIBs). The unique structural properties of the 1D single‐crystal nanobelts offer excellent electrochemical activity, electrochemo‐mechanical stability, and well‐maintained structural integrity, leading to highly efficient sodium ion storage performance. Insights into the electrochemical reaction processes, as revealed by in situ transmission electron microscopy, in situ synchrotron X‐ray diffraction, and theoretical calculations, indicate that the 1D single‐crystal nanobelts enable favorable sodium ion storage kinetics and a low‐strain characteristic. This facilitates fast charge/discharge capability and long‐term cycling stability for up to 5000 cycles at 20 C. Moreover, the 1D single‐crystal nanobelts demonstrate practical applicability. A pouch cell assembled with the 1D single‐crystal nanobelts anode and iron‐based Prussian blue cathode exhibits highly stable cycling, achieving a low capacity fading ratio of ≈0.05% per cycle over 150 cycles. This study provides an innovative design principle to enhance the charge storage capability of electrode materials through intelligent structural nanoengineering. [ABSTRACT FROM AUTHOR]

The document provides a comprehensive list of upcoming conferences, workshops, and fairs related to materials and corrosion. These events will be held in various locations around the world, including Germany, France, the United States, India, Italy, Canada, Turkey, Norway, Japan, Ireland, and the Czech Republic. The topics covered in these events range from bio-based coatings to artificial intelligence in materials science. Each event is organized by different organizations and societies, such as Vincentz Network, ASM International, ASTM, and the German Materials Society. More information about each conference can be found through the provided links. [Extracted from the article]

Polyoxometalates (POMs) are multifunctional anionic metal‐oxygen complexes with structural and electronic diversity, as well as tunable acid‐base and redox properties, resulting in their potential as building blocks for constructing temperature‐responsive polyoxometalates‐based materials (TRPMs). TRPMs represent a class of intelligent materials exhibiting property changes in response to temperature fluctuations, offering distinctive applications in various fields such as catalysis, medicine, sensors, imaging, and so on. Though many TRPMs are reported, a systematic review including recent advances is still absent. This review provides insights into recent advancements in temperature‐responsive mechanisms, nanostructure design strategies, and the characterization of TRPMs. Special emphasis is placed on enhancing the temperature‐responsive properties of TRPMs by incorporating POMs into suitable organic ligands, such as ionic liquid cations, deep eutectic solvent cations, cationic surfactants, and polymers. The incorporation of organic ligands with POMs not only enables temperature‐responsive phase transitions but also enhances other properties, such as catalyst selectivity and drug loading capacity, expanding TRPMs applications. Consequently, this review summarizes the applications of TRPMs in catalysis, drug delivery and release, and chemical sensing, as well as discusses future technological challenges. The in‐depth understanding of TRPMs may help in the design of TRPMs from the nanoscale, guiding and inspiring future development. [ABSTRACT FROM AUTHOR]

The field of photo-responsive electrospun polymer nanofibers represents a significant advancement in materials science, providing innovative solutions across various domains, including sensory technologies, medical treatments, environmental monitoring, and smart devices. These nanofibers, characterized by their responsiveness to light, offer unique opportunities due to their high surface area, porosity, and ability to incorporate diverse functional materials. Electrospinning, a versatile technique that produces nanofibers with tunable properties, allows for the customization of these fibers’ physical and chemical characteristics, making them ideal candidates for advanced applications. This review aims to provide a comprehensive overview of the development and applications of light-responsive polymer nanofibers. It discusses the techniques of integrating light-responsive functionalities into nanofibers, including chemical insertion and physical doping, and explores the diverse responses these nanofibers exhibit upon light exposure, such as photoisomerization, photochromism, photocatalysis, and alterations in wettability. The structure of the review includes an introduction to the fundamental principles of electrospinning and photo-responsiveness, followed by detailed sections on the various applications of these advanced materials. Finally, future research directions are suggested, focusing on the integration of multifunctional compounds and the exploration of advanced nanofiber morphologies to enhance the applicability and performance of these cutting-edge materials. [ABSTRACT FROM AUTHOR]

Electroactive polymers (EAPs) deform when subject to an electric field, which is generated by two or more electrodes. To ensure proper function of the EAP, these electrodes are connected to a source and they are therefore required to be continuous such that no isolated islands exist. Increasing an EAP's performance using topology optimization while ensuring electrode connectivity is the goal of this work. A topology optimization formulation is introduced where electrode connectivity is ensured using the virtual temperature method. Numerical experiments demonstrate that this is an efficient method to guarantee connectivity. [ABSTRACT FROM AUTHOR]

Modern spacecraft and launch vehicle design is more oriented towards reducing system-level design and assembly complexities. In order to maintain high overall system performance while reducing these complexities, the use of smart materials and smart structural components is a well-known practice and is currently of rising interest to space systems' designers. The paper discusses a concept of smart space structures, in particular, a carbon fiber composites structure embedded with Optical Fiber Sensors (OFS) for spacecraft and launch vehicle applications. This study highlights the operational requirements for such tank and the smart features enabled by the optical fiber sensors. For the latter aspect, a quantitative comparison between Fiber Bragg Grating sensors (FBGs) and Distributed Optical Fiber Sensors (DOFS) based on Optical Frequency Domain Reflectometry (OFDR) is presented to state their core performance parameters, such as the sensitivity, sensing range, dynamic measurement capability, and spatial resolution. The increased performance and reliability in harsh environments associated with fiber optic sensors come with a reduction in size, mass, and power consumption compared to the conventional electronic sensors. Optical fiber sensors embedded in carbon fiber structures have proven their capability in providing accurate real-time measurements of temperature and monitoring structural integrity while detecting precisely possible points of rupture and failure as discussed and demonstrated in the literature review. The applications of fiber optic sensing in smart propellant tanks may extend to detecting fluid leakage, also providing increased precision in propellant gauging through temperature mapping, and can be used in on-ground qualification, pre-flight testing, as well as in-orbit operation, condition, and structural health monitoring. The article presents a statement for an optimal FOS embedding approach in composite pressure vessels and discusses the related placement and orientation method for the fiber optic sensors, coupled with a one component simplified analytical stress-strain transfer model deriving the stress component along the maximum principal direction (i.e., σ Max P r i n c i p a l ). The novel approach is believed to serve the optimal employment of embedded FOS in composite structures, e.g., pressure vessels and light-weight structures in spacecraft, among other applications. The simplified model is believed to pave the way for effective data interpretation and processing, utilizing the available limited computational resources on-board the spacecraft. • Smart propellant tank embedding fiber optic sensors for structural health monitoring. • The opto-mechanical model defines the local stress in the maximum principal strain direction. • Quasi-distributed optic fiber sensors employing arrays of FBGs for spacecraft monitoring. • Distributed fiber optic sensing based on OFDR for spacecraft applications. [ABSTRACT FROM AUTHOR]

Smart hinges for self-deployable solar sails have been prototyped by using shape memory polymer composites (SMPCs). During hinge lamination, a shape memory (SM) epoxy resin is deposited between carbon fiber reinforced (CFR) plies, and consolidation is obtained by an out-of-autoclave (OOA) process. The smart hinges have been assembled with CFR booms to prototype a small self-deployable square sail. Polymeric supports, made by fused deposition modelling (FDM), have been added for correct assembly and to drive the recovery of the SMPC hinges. Flexible heaters have been used as heating elements for SMPC hinge activation. The sail consisted of a polyimide membrane which was connected with the composite booms by flexible joints. The solar sail prototype size has been limited to 260 × 260 mm2 for on-Earth testing, with 4 hinges at the middle length of the composite booms. Recovery tests have shown the ability of the smart hinges to overcome the sail weight and additional friction forces, and the small sail has been successfully deployed in laboratory. Full recovery has been achieved in less than 3 min under different configurations. [ABSTRACT FROM AUTHOR]

Smart dental materials refer to materials used in dentistry with additional functionality to enhance treatment outcomes, which may improve oral health. Smart materials for dental restorations can react to stimuli such as a specific temperature, a different pH, or mechanical stress, repair small cracks or damage by themselves, and interact beneficially with biological surroundings. For example, they might release ions and promote tooth remineralization or have antibacterial properties to prevent bacterial growth. Others can have enhanced mechanical properties like strength and wear resistance to ensure these materials can withstand daily masticatory forces. This review presents our current comprehension of smart dental materials designed for tooth restoration. We focused on what these materials need to be effective, like durability, biocompatibility, and aesthetic requests, besides identifying new ideas for their design. A detailed analysis of the current challenges in formulating these materials, such as the balance between enough ions released with proper physicochemical properties and achieving the desired biological response, was discussed. We also discussed how these cutting-edge technologies are leveraged to overcome existing limitations, creating more dental materials with potential clinical translation. The review also discusses the practical challenges in implementation and the prospects for these materials in dentistry. [ABSTRACT FROM AUTHOR]

The text discusses the importance of sustainability in geotechnics, focusing on the integration of new materials and technologies to mitigate climate change while ensuring safety and stability. The Special Issue "Sustainability in Geotechnics" features contributions from nine countries across three continents, addressing topics such as mining tailings recovery, soil stabilization, and slope stability assessment. By embracing sustainable practices and innovative solutions, geotechnical engineers can contribute to a greener and more sustainable future, shaping a resilient built environment for modern society. [Extracted from the article]