In the human body, many soft tissues with hierarchically ordered composite structures, such as cartilage, skeletal muscle, the corneas, and blood vessels, exhibit highly anisotropic mechanical strength and functionality to adapt to complex environments. In artificial soft materials, hydrogels are analogous to these biological soft tissues due to their “soft and wet” properties, their biocompatibility, and their elastic performance. However, conventional hydrogel materials with unordered homogeneous structures inevitably lack high mechanical properties and anisotropic functional performances; thus, their further application is limited. Inspired by biological soft tissues with well‐ordered structures, researchers have increasingly investigated highly ordered nanocomposite hydrogels as functional biological engineering soft materials with unique mechanical, optical, and biological properties. These hydrogels incorporate long‐range ordered nanocomposite structures within hydrogel network matrixes. Here, the critical design criteria and the state‐of‐the‐art fabrication strategies of nanocomposite hydrogels with highly ordered structures are systemically reviewed. Then, recent progress in applications in the fields of soft actuators, tissue engineering, and sensors is highlighted. The future development and prospective application of highly ordered nanocomposite hydrogels are also discussed.

Many biological organisms with exceptional freezing tolerance can resist the damages to cells from extra-/intracellular ice crystals and thus maintain their mechanical stability at subzero temperatures. Inspired by the freezing tolerance mechanisms found in nature, here we report a strategy of combining hydrophilic/oleophilic heteronetworks to produce self-adaptive, freeze-tolerant and mechanically stable organohydrogels. The organohydrogels can simultaneously use water and oil as a dispersion medium, and quickly switch between hydrogel- and organogel-like behaviours in response to the nature of the surrounding phase. Accordingly, their surfaces display unusual adaptive dual superlyophobic in oil/water system (that is, they are superhydrophobic under oil and superoleophobic under water). Moreover, the organogel component can inhibit the ice crystallization of the hydrogel component, thus enhancing the mechanical stability of organohydrogel over a wide temperature range (−78 to 80 °C). The organohydrogels may have promising applications in complex and harsh environments.

Many biological organisms can tune their mechanical properties to adapt to environments in multistable modes, but the current synthetic materials, with bistable states, have a limited ability to alter mechanical stiffness. Here, we constructed programmable organohydrogels with multistable mechanical states by an on-demand modular assembly of noneutectic phase transition components inside microrganogel inclusions. The resultant multiphase organohydrogel exhibits precisely controllable thermo-induced stepwise switching (i.e., triple, quadruple, and quintuple switching) mechanics and a self-healing property. The organohydrogel was introduced into the design of soft-matter machines, yielding a soft gripper with adaptive grasping through stiffness matching with various objects under pneumatic-thermal hybrid actuation. Meanwhile, a programmable adhesion of octopus-inspired robotic tentacles on a wide range of surface morphologies was realized. These results demonstrated the applicability of these organohydrogels in lifelike soft robotics in unconstructed and human body environments.

Shape memory effect in polymer materials has attracted considerable attention due to its promising applications in a variety of fields. However, shape memory polymers prepared by conventional strategy suffer from a common problem, in which high strain capacity and excellent shape memory behavior cannot be simultaneously achieved. This study reports a general and synergistic strategy to fabricate high-strain and tough shape memory organohydrogels that feature binary cooperative phase. The phase- transition micro-organogels and elastic hydrogel framework act synergistically to provide excellent thermomechanical performance and shape memory effect. During shape memory process, the organohydrogels exhibit high strain capacity, featuring fully recoverable stretching deformation by up to 2600% and compression by up to 85% beneath a load ≈20 times the organohydrogel's weight. Furthermore, owing to the micro-organogel and hydrogel heterostructures, the interfacial tension derived from heterophases dominates the shape recovery of the organohydrogel material. Simple processing and smart surface patterning of the shape memory behavior and multiple shape memory effects can also be realized. Meanwhile, these organohydrogels are also nonswellable in water and oil, which is important for multimedia applications.

A fabrication strategy for biphasic gels is reported, which incorporates high-internal-phase emulsions. Closely packed micro-inclusions within the elastic hydrogel matrix greatly improve the mechanical properties of the materials. The materials exhibit excellent switchable mechanics and shape-memory performance because of the switchable micro- inclusions that are incorporated into the hydrogel matrix. The produced materials demonstrated a self-healing capacity that originates from the noncovalent effect of the biphasic heteronetwork. The aforementioned characteristics suggest that the biphasic gels may serve as ideal composite gel materials with validity in a variety of applications, such as soft actuators, flexible devices, and biological materials.

for applications in aerospace, smart devices, and biomedical materials. [1][2][3] Among these materials, shape-morphing polymers (SMPs) are particularly attractive because their forms can be programmed to perform transformations or motions in response to external stimuli (e.g., temperature, light, solvent, and electric fields). [3][4][5][6][7][8][9][10][11] Currently, two general approaches are used to obtain unparalleled shape-programming flexibility. The first involves geometric assistances to produce complex SMP shapes, such as kirigami and origami art, as well as 3D printing. [12][13][14][15][16][17] Alternatively, another approach is through the use of an innovational polymer network design, which employs functional components to expand the programmability of SMPs. [18][19][20][21][22][23] For example, SMPs with dynamic covalent polymer networks and reversible crosslinking netpoints exhibit unique shape reconfiguration and programmability. [18][19][20][21] However, despite these exciting prospects, most SMPs with the single control routes only allow complex temporary shapes to recover a former permanent state, ultimately limiting the versatility of these materials and our ability to control them for complex applications. Owing to the intrinsic restriction of the permanently crosslinked polymer network, such single programming inevitably lacks a mechanism Programmable materials that can change their inherent shapes or properties are highly desirable due to their promising applications. However, among various programmable shape-morphing materials, the single control route allows temporary states to recover the unchangeable former state, thus lacking the sophisticated programmability for their shape-encoding behaviors and mechanics. Herein, dual-programmable shape-morphing organohydrogels featuring supramolecular heteronetworks are developed. In the system, the metallo-supramolecular hydrogel framework and micro-organogels featuring semicrystalline comb-type networks independently respond to different stimuli, thereby providing orthogonal dual-switching mechanics and ultrahigh mechanical strength. The supramolecular heteronetworks also possess excellent self-healing properties. More notably, such orthogonal supramolecular heteronetworks demonstrate hierarchical shape morphing performance that far exceeds conventional shape-morphing materials. Utilizing this dual programming strategy of the orthogonal supramolecular heteronetworks, the material's permanent shape can be manipulated in a step-wise shape morphing process, thereby realizing sophisticated shape changes with a high degree of freedom. The organohydrogels can act as a biomimetic smart device for the on-demand control of unidirectional liquid transport. Based on these characteristics, it is anticipated that the supramolecular organohydrogels may serve as adaptive programmable materials for a variety of applications. Gel MaterialsProgrammable materials are capable of changing their inherent shapes or exquisite properties to adapt to complex environments a...

Adaptive materials with reconfigurable surface topography in response to external environments have attracted considerable attention in various fields. Here, adaptive superamphiphilic organohydrogels with reconfigurable surface topography are reported, featuring a high degree of freedom. The organohydrogels can simultaneously adapt to different surrounding mediums and reversibly switch between hydrogel-and organogeldominated surface reconfigurations to realize adaptive superhydrophilic and superoleophilic transitions. Meanwhile, these adaptive organohydrogels possess a heteronetwork complementary effect to elicit surface self-healing capacity. Importantly, owing to these organohydrogels' reversible wettability transition, excellent surface morphing performance and bioinspired strategy, various geometrically complex biomimetic topographies can be programmed, offering unique unidirectional transport for opposite-featured liquids in multimedia environments. Smart organohydrogel-based microfluidic devices are also developed for on-demand remote programming of liquid transport. Therefore, the organohydrogels suggest a reconfigurable surface topography design strategy, and would act as adaptive programmable materials for smart surface applications.

Janus composite nanosheets of PNIPAM/silica/PDEAEMA are synthesized by sequential ATRP grafting two polymers from the corresponding sides of the Janus silica nanosheets. They are dually responsive to pH and temperature since wettability of the two sides is tunable accordingly. The nanosheets can serve as a responsive solid emulsifier. Type and stability of the emulsions are triggered by simply changing pH and temperature.