Load-bearing biological tissues, such as muscles, are highly fatigue-resistant, but how the exquisite hierarchical structures of tissues contribute to their excellent fatigue resistance is not well understood. In this work, we study antifatigue properties soft materials with using polyampholyte hydrogels (PA gels) a simple model system. PA gels tough and self-healing, consisting reversible ionic bonds at 1-nm scale, cross-linked polymer network 10-nm bicontinuous hard/soft phase networks...

Significance Life provides the best demonstration of complex and adaptive nonequilibrium system, which executes biological functions through structure transformation. Creating lifelike materials to achieve part or full is a grand challenge. Traditional memories from hard dry are static, with no ability forgetting; here we propose use soft wet hydrogels dynamic spontaneous but learning-strength-dependent forgetting by using transformation, in analogy human brain. We believe concept...

Polyampholyte hydrogels (PA gels) are drawing great attention for their excellent mechanical properties including self-healing, high toughness, and fatigue resistance. These performances found to be attributed the hierarchical structure of PA gels, consisting reversible ionic bonds at 1 nm scale, permanent polymer network 10 bicontinuous phase 100 scale. In this work, we systematically studied formation these gels aiming answer following three questions: (1) how separation occurs? (2) what...

The multilevel fatigue resistance mechanism of tough and self-healing hydrogels with a hierarchical structure was revealed.

Phase-transformable ionic conductors (PTICs) show significant prospects for functional applications due to their reversible resistance switching property. However, the representative design principle of PTICs is utilizing melt-crystallization transition liquids, and temperatures such cannot be tuned as desired. Herein, a new strategy proposed with on-demand by using polymer cocrystal phase, whose melting temperature shows linear relationship compositions. Owing melt domains tunable migration...

Adhesion-switchable ionogels with ultralow hysteresis are developed through moisture-mediated phase separation using opposite-affinity ionic components. These show great potential in smart adhesives for targeted object capture.

Poly(glycolic acid) (PGA) is a unique biodegradable, aliphatic polyester having higher melting point (Tm) and better mechanical properties chemical resistance than its analogs. The unusual physical of PGA can be attributed to crystalline structure, chain packing interactions. Herein, we systematically investigated the spherulitic morphology, structural evolution in crystallization processes by time-resolved wide-angle X-ray diffraction (WAXD) FTIR spectrometry. exhibits fast it completely...

Soft materials with mechanical adaptability have substantial potential for various applications in tissue engineering. Gaining a deep understanding of the structural evolution and adaptation dynamics soft subjected to cyclic stretching gives insight into developing mechanically adaptive materials. Here, we investigate effect hierarchy structure on self-healing hydrogels under training. A polyampholyte hydrogel, composed hierarchical structures including ionic bonds, transient permanent...

Hydrogels have emerged as promising candidates for anticounterfeiting materials, owing to their unique stimulus-responsive capabilities. To improve the security of encrypted information, efforts are devoted constructing transient hydrogels with a dynamic information display. However, current studies design such hydrogel materials inevitably include sophisticated chemistry, complex preparation processes, and particular experimental setups. Herein, facile strategy is proposed realize by...

The magnetization reversal in four arrays of micron-size circular holes (antidots) a Permalloy film has been studied by means quantitative magneto-optic Kerr vector magnetometry and magnetic force microscopy. primitive antidot meshes the investigated here can be classified as square, rectangular, hexagonal, oblique. data show that hole induce anisotropy completely different from unpatterned film, with new hard axes along directions connecting nearest neighboring holes. Also coercive field is...

It has been shown previously that the thermoelectric properties of Zintl phase compound, YbZn2Sb2 can be finely tuned via substitution at cationic Yb-site. Here we report results investigation isoelectronic Zn by Mn in anionic (Zn2Sb2)2− framework. The p-type YbZn2−xMnxSb2 (0.0⩽x⩽0.4) samples have synthesized a solid-state reaction followed suitable cooling, annealing, grounding, and hot-pressing densification processes. In with x=0.0, 0.05, 0.10, 0.15, 0.2, 0.3, 0.4, electrical...

Supramolecular polymers (SMPs) have quite different crystallization behavior from the conventional polymers, because of confinement effects supramolecular units. Crystallization SMPs undergoes in a "confined" and "dynamic" manner. Herein, we selected 2-ureido-4[1H]-pyrimidione (UPy)-bonded poly(l-lactic acid) (PLLA) as model SMP investigated kinetics, polymorphic crystalline structure phase transition PLLAs (SM-PLLAs). SM-PLLAs were synthesized by end functionalization hydroxyl-terminated 2-...

Promoting the stereocomplexation ability of high-molecular-weight poly(l-lactic acid) (PLLA) and poly(d-lactic (PDLA) is an efficient way to improve thermal resistance resulting materials. Herein, we studied competing crystallization kinetics, polymorphic crystalline structure, lamellae structure PLLA/PDLA component in its miscible blends with poly(vinyl acetate) (PVAc) proposed a method PLLA PDLA through blending other polymer. Crystallization suppressed after addition PVAc, due dilution...

Due to the effects of microphase separation and physical dimensions, confinement widely exists in multi-component polymer systems (e.g., blends, copolymers) polymers having nanoscale such as thin films nanofibers. Semicrystalline usually show different crystallization kinetics, crystalline structure morphology from bulk when they are confined environments; this may dramatically influence performances resulting materials. Therefore, investigations on spherulitic semicrystalline essential both...

The tough and self-healing hydrogels composed of polyampholytes (PA gels) are drawing great attention due to their multiscale structures the resultant multiple mechanical properties. This work studies stress relaxation behavior PA gels reveals underlying structure evolutions by combining birefringence small-angle X-ray scattering measurements. show a fast strong that obeys stress-optical rule, which could be associated with chain segment orientation breaking ionic bonds. A slow weak phase...

ConspectusWidespread in chemistry and biochemistry, chirality strongly affects the biological, chemical, material, physical properties. As a downstream derivative, enantiopure polymers of opposite can cocrystallize stereocomplex (SC) their enantiomeric blends or block copolymers, which endows materials with improved properties specific functions such as enhanced melting temperature, thermal stability, crystallizability, hydrolytic resistance. A well-studied stereocomplexable polymer is...

Abstract The growing urgence of information protection promotes continuously the development information‐encryption technique. To date, hydrogels have become an emerging candidate for advanced materials, because their unique stimulus responsiveness. However, current methods to design multi‐level information‐encrypted usually need sophisticated chemistry or experimental setup. Herein, a novel strategy is reported fabricate with encryption/decryption functions through spatially programming...

Polymorphism and crystal transition are common phenomena of semicrystalline polymers. These two behaviors known to be controlled by the nucleation chain mobility polymers, both which constrained entanglement at molecular level. However, role in polymorphic crystallization phase polymers has not been well understood. Herein, we use isotactic polybutene-1 (PB-1) as a model polymer present crucial kinetics solid-solid transition. A series less-entangled PB-1 with different degrees were...

Understanding the physical principle that governs stimuli-induced swelling and shrinking kinetics of hydrogels is indispensable for their applications. Here, we show self-healing could be intrinsically asymmetric. The structure frustration, formed by large difference in heat solvent diffusions, remarkably slows down kinetics. plateau modulus viscoelastic gels found to a key parameter governing formation frustration and, turn, asymmetric This work provides fundamental understandings on...

Copolymerization of diacids and diamines can produce copolyamides with diversified physical properties. Due to the interplay between even–even odd–even diamine-diacid units, even–even/odd–even show much different crystal polymorphism phase transition behavior from typical (co)polyamides. Herein, we synthesized novel nylon 5,6 6,6 salts investigated their crystallization kinetics, crystalline structure, behavior. The display isodimorphic behavior, solution-crystallized experience α–γ Brill...

Objective: To reduce hip joint muscles’ activation during walking with an active exoskeleton. Background: Few studies examine the optimal assistance timing of exoskeleton based on muscle characteristics. Methods: Sixteen gender-balanced healthy adults (mean age 28.8 years) performed four tasks (each over 20 min). Tasks were different in loading and assistance. Muscle was collected by surface electromyography. The oxygen consumption evaluated performance proposed strategy. Results:...