A Stiffness‐Switchable, Biomimetic Smart Material Enabled by Supramolecular Reconfiguration

Abstract

In nature, stiffness‐changing behavior is essential for living organisms, which, however, is challenging to achieve in synthetic materials. Here, a stiffness‐changing smart material, through developing interchangeable supramolecular configurations inspired from the dermis of the sea cucumber, which shows extreme, switchable mechanical properties, is reported. In the hydrated state, the material, possessing a stretched, double‐stranded supramolecular network, showcases a soft‐gel behavior with a low stiffness and high pliability. Upon the stimulation of ethanol to transform into the coiled supramolecular configuration, it self‐adjusts to a hard state with nearly 500‐times enhanced stiffness from 0.51 to 243.6 MPa, outstanding load‐bearing capability (over 35 000 times its own weight), and excellent puncture/impact resistance with a specific impact strength of ≈116 kJ m−2 (g cm−3)−1 (higher than some metals and alloys such as aluminum, and even comparable to the commercially available protective materials such as D3O and Kevlar). Moreover, this material demonstrates reconfiguration‐dependent self‐healing behavior and designable formability, holding great promise in advanced engineering fields that require both high‐strength durability and good formability. This work may open up a new perspective for the development of self‐regulating materials from supramolecular‐scale configuration regulation.

Bioinspired Hydrogels as Platforms for Life-Science Applications: Challenges and Opportunities

“…Similar to the dermis of the sea cucumber, the variable stiffness is important for living organisms. Inspired from the dermis, stiffness-changing smart materials with interchangeable hydrogels with switchable mechanical properties were developed [162]. The doublestranded supramolecular network showed reconfiguration-dependent self-healing behavior and tuned formability, being a promising biomimetic material with high durability.…”

Tailored one-pot lignocellulose fractionation to maximize biorefinery toward versatile xylochemicals and nanomaterials

“…For the solid stream, near-quantitative conversion of the cellulose component was valorized to glucose, nanocellulose or nanomaterials. 47,48 In the liquid stream, lignin fractions were easily recovered with a yield of 70% as a potential source of aryl ether-retained lignin polyols. After a further RCF process, 69% yield of alkylphenol monomers relative to MWL was obtained.…”

Cellulose Nanopaper: Fabrication, Functionalization, and Applications

“…As the most abundant natural polymer, cellulose is the main structural component of plant’s cell wall (Fig. 1 a, c) and many microorganisms (such as fungi, bacteria, and algae) [ 1 , 2 ]. Cellulose is composed of β-D-glucopyranose units linked by β-(1–4) glycosidic bonds [ 3 – 5 ].…”