Molecularly Engineered Dual‐Crosslinked Hydrogel with Ultrahigh Mechanical Strength, Toughness, and Good Self‐Recovery

Abstract

A molecularly engineered dual-crosslinked hydrogel with extraordinary mechanical properties is reported. The hydrogel network is formed with both chemical crosslinking and acrylic-Fe(III) coordination; these, respectively, impart the elasticity and enhance the mechanical properties by effectively dissipating energy. The optimal hydrogel achieves a tensile stress of ca. 6 MPa at a large elongation ratio (>7 times), a toughness of 27 MJ m(-3) , and a stiffness of ca. 2 MPa, and has good self-recovery properties.

Tough Physical Double‐Network Hydrogels Based on Amphiphilic Triblock Copolymers

“…On the other hand, the B-DN3 gel with strong physical hydrophobic associations and sacrifi cial hydrogen bonds, shows a high elastic modulus of 2.2 ± 0.2 MPa, fracture stress of 10.5 ± 1.4 MPa, and fracture strain of 5.7 ± 0.7 mm mm −1 (Figure 3 a). Different from other DN gels and other tough hydrogels that show yielding or strain softening [5][6][7][8][9][10][11][12] this gel shows an unusual linear stress-strain curve up to the fracture strain of 600%. Meanwhile, the S-S curve shows large hysteresis in cyclic tensile tests ( Figure 4 ), and at room temperature the B-DN3 gel shows partial self-recovery properties.…”

“…In recent work, partially or completely recoverable tough hydrogels were successfully synthesized by using ionic bonds as recoverable sacrifi cial bonds. [8][9][10][11][12] However, ionic bonds are unstable in saline conditions, which limits the suitability of these materials in some physiological and mechanical applications. [ 9 ] In the recent work, hybrid hydrogels, which …”

Directed Motility of Hygroresponsive Biomimetic Actuators

“…[6][7][8][9][10][11][12][13][14][15][16][17][18] These materials are normally based on photoresponsive, thermoresponsive, chemoresponsive, electroactive, or hygrosensitive smart polymers. [19][20][21][22][23][24][25][26][27][28][29][30][31] However, precise external spatiotemporal control over the dynamics and kinematics of such biomimetic materials continues to posit a considerable challenge. With photomechanical actuators that are capable of externally controllable mechanical motion in response to light, generally one of two approaches to external control of motility is adopted.…”

Self-Healing Hydrogels as Biomedical Scaffolds for Cell, Gene and Drug Delivery

“…Hydrogels, due to its intrinsic structural inhomogeneity or lacking effective energy dissipation mechanism, usually have poor rheological and mechanical properties [53] . Although hydrogels seem to be fragile, there are many tissues such as (tendons, ligaments, meniscus and cartilage) even creatures (jellyfish and sea anemones) in hydrogel-like state [54] .…”