Monomer Trapping Synthesis Toward Dynamic Nanoconfinement Self-healing Eutectogels for Strain Sensing.

The rapid advancement in attractive platforms such as biomedicine and human-machine interaction has generated urgent demands for intelligent materials with high strength, flexibility, and self-healing capabilities. However, existing self-healing ability materials are challenged by a trade-off between high strength, low elastic modulus, and healing ability due to the inherent low strength of noncovalent bonding. Here, drawing inspiration from human fibroblasts, a monomer trapping synthesis strategy is presented based on the dissociation and reconfiguration in amphiphilic ionic restrictors (7000-times volume monomer trapping) to develop a eutectogel. Benefiting from the nanoconfinement and dynamic interfacial interactions, the molecular chain backbone of the formed confined domains is mechanically reinforced while preserving soft movement capabilities. The resulting eutectogels demonstrate superior mechanical properties (1799% and 2753% higher tensile strength and toughness than pure polymerized deep eutectic solvent), excellent self-healing efficiency (>90%), low tangential modulus (0.367 MPa during the working stage), and the ability to sensitively monitor human activities. This strategy is poised to offer a new perspective for developing high strength, low modulus, and self-healing wearable electronics tailored to human body motion.

Bioinspired H-Bonding Connected Gradient Nanostructure Actuators Based on Cellulose Nanofibrils and Graphene.

The construction of flexible actuators with ultra-fast actuation and robust mechanical properties is crucial for soft robotics and smart devices, but still remains a challenge. Inspired by the unique mechanism of pinecones dispersing seeds in nature, a hygroscopic actuator with interlayer network-bonding connected gradient structure is fabricated. Unlike most conventional bilayer actuator designs, the strategy leverages biobased polyphenols to construct strong interfacial H-bonding networks between 1D cellulose nanofibers and 2D graphene oxide, endowing the materials with high tensile strength (172 MPa) and excellent toughness (6.64 MJ m-3). Furthermore, the significant difference in hydrophilicity between GO and rGO, along with the dense interlayer H-bonding, enables ultra-fast water exchange during water absorption and desorption processes. The resulted actuator exhibits ultra-fast driving speed (154° s-1), excellent pressure-resistant and cyclic stability. Taking advantages of these benefits, the actuator can be fabricated into smart devices (such as smart grippers, humidity control switches) with significant potential for practical applications. The presented approach to constructing interlayer H-bonding in gradient structures is instructive for achieving high performance and functionalization of biomass nanomaterials and the complex of 1D/2D nanomaterials.

Poly[µ(3)-aqua-µ(2)-2,4-dinitro-phenolato-rubidium(I)].

The asymmetric unit of the title compound, [Rb(C(6)H(3)N(2)O(5))(H(2)O)](n), comprises a rubidium cation, a 2,4-dinitro-phenoxide anion and a water mol-ecule. The Rb(+) cation is 11-coordinated by O atoms from 2,4-dinitro-phenolate anions and water mol-ecules. The metal centre is firstly coordinated by two µ(3)-H(2)O to form a one-dimensional ladder-shaped unit, [Rb(2)(µ(3)-H(2)O)(2)], which is further linked by 2,4-dinitro-phenolate to give the three-dimensional framework of the title compound. The crystal structure involves O-H⋯O hydrogen bonds.