Chuanzhuang Zhao

The Hofmeister series provides an empirical description of ion-specific effects, yet a quantitative framework connecting ion-specific hydration to polymer relaxation has remained elusive. Here, we establish such a framework for hydrogen-bonded hydrogels by introducing the dimensionless parameter Bc (the product of the Jones–Dole viscosity B coefficient and salt concentration c) as a quantitative descriptor of the hydration environment. Using poly(methacrylamide) (PMAm) hydrogels as a model system, we show that the effects of ion identity and salt concentration on polymer relaxation can be quantitatively correlated through Bc. Within the water-abundant regime (Bc < 0.2), polymer relaxation follows the scaling relationship ln(τp) ∼ Bc, whereas this scaling gradually deviates as the system enters the water-depleted regime (Bc > 0.2). This deviation suggests that polymer relaxation becomes progressively less dependent on hydration-mediated processes as the hydration environment becomes increasingly constrained. The resulting Bc framework provides a quantitative correspondence among ion identity, salt concentration, and temperature through their effects on polymer relaxation. This framework provides a quantitative basis for tuning hydrogel viscoelasticity and shape-memory actuation through salt-mediated modulation of the hydration environment. More broadly, the framework extends the Hofmeister effect from an empirical ion ordering to a quantitative description of relaxation behavior for hydrogen-bonded polymer networks by linking the hydration environment with polymer dynamics.

Dynamic hydrogels face the challenge of balancing performance robustness with dynamic responsiveness, and traditional strategies often fail to address both. Inspired by the synergistic regulation of structure and function through multiple weak interactions in biological systems, this review examines how synergistic strategies centered on hydrogen bonding can resolve this contradiction. We explore how hydrogen bonds, with their short‐range, directional, and reversible properties, form hierarchical synergistic networks with hydrophobic interactions, metal coordination, electrostatic interactions, and dipole interactions. Additionally, we emphasize the role of the solvent environment in coordinated regulation, revealing how ions, organic solvents, and small molecules indirectly modulate interpolymer hydrogen bonds by restructuring the hydrogen bond network of water or directly participating in competitive binding, thus governing the macroscopic performance of gels. Based on these synergistic principles, we describe their applications in realizing hydrogel functions such as high strength and toughness, impact resistance, adhesion, self‐healing, actuation, shape memory, and luminescence. Finally, we provide an outlook on emerging frontiers, including data‐driven design paradigms based on biological data mining and machine learning, as well as the integration of living cells to construct adaptive life‐material hybrid systems for next‐generation intelligent soft materials.

A critical challenge in multifunctional room‐temperature phosphorescent (RTP) hydrogels is the balance between the persistent afterglow and the editable phosphorescent information. Inspired by the Hawaiian bobtail squid ( Euprymna scolopes ), which modulates bioluminescence through symbiotic bacterial storage and release, a biomimetic RTP hydrogel system is introduced that overcomes this limitation. The hydrogel, synthesized via polymerization of acrylic acid (AA) with diethylenetriamine (DETA), followed by Ca ²⁺ coordination with COO ⁻ in polyacrylic acid (PAA) chains, exhibits remarkable phosphorescence (afterglow > 6.5 s) and three synergistic functionalities: 1) Dynamic information re‐editability via water erasing and salt printing for real‐time information programming; 2) Thermomechanical responsiveness enabling reversible stiffness modulation and thermal concealment of photonic information; 3) Self‐healing through dynamic hydrogen bonding, facilitating dynamic reconfiguration of luminescent patterns. This RTP hydrogel establishes a robust platform for the edition of information, which emphasizes the potential of bioinspired strategies for advancing intelligent materials in bioimaging, flexible displayers, and information encryption.

Bioadhesives have emerged as versatile and powerful tools for tissue repair and integration with biomedical devices, offering a wide range of applications that have captured significant clinical and scientific interest. Synthetic polypeptide adhesives are particularly promising candidates for bioadhesives, but often face limitations in adhesive strength. In this study, inspired by marine adhesive proteins, the secondary structure and hydrophobic-hydrophilic balance of polypeptides were precisely regulated to transform the polyelectrolyte to a strong adhesive. The resulting polypeptide adhesive demonstrated an adhesive strength exceeding 1.0 MPa, more than 10× higher than that of the previously reported synthetic polypeptide adhesive. The cohesion and adhesion of polypeptide adhesive can be optimized by adjusting the content of the secondary structure and hydrophobic residue ratios. More helices in polypeptides enhance the interactions between the polypeptide backbone and side chains as well as the interactions between polypeptides and substrates. In addition, these polypeptide adhesives exhibit excellent tolerance to strong acids or alkalis, remarkable adhesion to variable materials and tissues, and an impressive sealing performance.

Crystalline colloidal arrays (CCAs) composed of core–shell microspheres with thermoresponsive structural iridescence governed by Bragg's law have garnered significant attention for diverse applications. While core–shell microspheres with lower critical solution temperature (LCST) properties are extensively studied, upper critical solution temperature (UCST) counterparts remain unexplored, offering the potential to expand the application scope of thermoresponsive CCAs. In this study, poly(N‐acryloyl glycinamide) (PNAGA), a UCST homopolymer, is employed for the first time to synthesize core–shell microspheres. By copolymerizing NAGA with the hydrophilic co‐monomer acrylamide (AM) to form the shell, microspheres with soft shells capable of assembling into CCAs with bright iridescence are obtained. Owing to Bragg's law and the UCST properties of the shell, the diffraction wavelength of these CCAs depends on concentration, observation angle, and temperature. The CCAs exhibit thermoresponsive behavior, with a size transition temperature around 14°C. Upon heating, the shells swell, and the microspheres transition from a rigid to a soft state, leading to an increase in interparticle distance and enhanced stabilization of the ordered microsphere packing. This process results in a red shift and a significant increase in the intensity of the diffraction peak. The thermoresponsive properties of these CCAs highlight their potential as intelligent temperature‐sensing materials.