Artificial spider silk from ion-doped and twisted core-sheath hydrogel fibres

Abstract

Spider silks show unique combinations of strength, toughness, extensibility, and energy absorption. To date, it has been difficult to obtain spider silk-like mechanical properties using non-protein approaches. Here, we report on an artificial spider silk produced by the water-evaporation-induced self-assembly of hydrogel fibre made from polyacrylic acid and silica nanoparticles. The artificial spider silk consists of hierarchical core-sheath structured hydrogel fibres, which are reinforced by ion doping and twist insertion. The fibre exhibits a tensile strength of 895 MPa and a stretchability of 44.3%, achieving mechanical properties comparable to spider silk. The material also presents a high toughness of 370 MJ m−3 and a damping capacity of 95%. The hydrogel fibre shows only ~1/9 of the impact force of cotton yarn with negligible rebound when used for impact reduction applications. This work opens an avenue towards the fabrication of artificial spider silk with applications in kinetic energy buffering and shock-absorbing.

Multi-Sacrificial Bonds Enhanced Double Network Hydrogel with High Toughness, Resilience, Damping, and Notch-Insensitivity

“…Figure 1 presents the preparation process and interactions of the CDN-gel. The alkoxy groups are first hydrolyzed into silanol groups in the presence of water, and the silanol groups then condensate to form a siloxane bond [ 24 , 25 ]. The free-radical grafting polymerization mechanism of the PVA/PAA hydrogel triggered by visible light with a CQ initiator was proposed in our previous work [ 20 ].…”

Redox‐Active Iron‐Citrate Complex Regulated Robust Coating‐Free Hydrogel Microfiber Net with High Environmental Tolerance and Sensitivity

“…1D conductive hydrogel microfibers could be the most important example of miniaturized hydrogels, whose fabrication are facing two main problems nevertheless: Dehydration versus conductivity: severe dehydration easily occurs as the fiber is spun in air, although a few researches have highlighted the significance of dehydration for enhancing the fiber strength and stretchability 11–13. There seems to be a trade‐off for bare hydrogel microfibers between fiber strength and ionic conductivity, which depend on adverse water contents.…”

“…To circumvent this issue, recently Ma et al reported a core–shell stretchable and conductive sodium polyacrylate hydrogel microfiber with a thin elastomer coating layer to prevent dehydration while maintaining good fiber elasticity 14. Nonetheless, the inert elastomer coating evitably leads hydrogel microfiber to be insensitive to environmental changes, which are unfavorable for sensing applications. Spinnability versus fiber strength: compared to electrospinning15,16 and extrusion spinning,9,10,17,18 microfluidic or draw‐spinning inspired from spider spinning procedure11–14,19,20 seems to be more suitable for fabricating long and uniform hydrogel microfibers. However, unless using the strategy of full dehydration, it is still challenging to compromise the spinnability and mechanical strength of hydrogel microfibers.…”

“…Spinnability versus fiber strength: compared to electrospinning15,16 and extrusion spinning,9,10,17,18 microfluidic or draw‐spinning inspired from spider spinning procedure11–14,19,20 seems to be more suitable for fabricating long and uniform hydrogel microfibers. However, unless using the strategy of full dehydration, it is still challenging to compromise the spinnability and mechanical strength of hydrogel microfibers.…”

Ductile cooling phase change material

“…[14][15][16][17][18] On the other hand, the high-water content in hydrogels leads to the liquidlike attributes of hydrogels, including permeability to a wide range of chemical and biological molecules, and transparency to optical and acoustic waves. [19][20][21][22] Moreover, the unique properties of hydrogels, such as its superior soness, wetness, responsiveness, biocompatibility, and bioactivity, indeed suggest the possibility of their crucial functions in cooling applications. 23,24 The heat absorption due to water content in hydrogels makes it a cooling device, [25][26][27][28][29] while water is abundant, non-corrosive, non-toxic, and non-ammable.…”