Wearable Superhydrophobic Elastomer Skin with Switchable Wettability

Abstract

Flexible smart surfaces with tunable wettability are promising for emerging wearable uses. However, currently, wearable superhydrophobic surfaces with dynamic wetting behaviors are rarely reported. Here, a skin-like superhydrophobic elastomer surface with switchable lotus leaf and rose petal states is reported. Direct laser writing technique is employed for one-step, programmable, large-scale fabrication of monolithic and hierarchical micronanostructures on elastomer, leading to strong water repellence. The surface topography can be finely regulated in a rapid and reversible manner by simple stretching, providing the feasibility of controlling the surface wettability by simple body motions. The ability to switch wetting states enables the surface to capture and release multiple droplets in parallel. Furthermore, the active surface can be applied to the joints of fingers and operate as a droplet manipulator under finger motions without requiring energy supply or external appliance. In this work, dynamic tuning of wetting properties is integrated into the design of skin-like wearable surfaces, revealing great potential in versatile applications such as wearable droplet manipulator, portable actuator, adaptive adhesion control, liquid repellent skin, and smart clothing.

Reversible Structure Engineering of Bioinspired Anisotropic Surface for Droplet Recognition and Transportation

“…It is quite different from the previous reports that the strong adhesion of a droplet on the surface mainly originates from the Wenzel mode, which makes these surfaces can hardly change from the strong sticky to the easy sliding state, not to mention in situ. [ 8,10a ] Statistically, there was no significant difference between L A and L 0 (Figure 4C), which confirms the sticking of water droplet on the surface.…”

One‐component waterborne in vivo cross‐linkable polysiloxane coatings for artificial skin

“…It can be topically applied to human skin without the need of skill and cross‐linked in vivo at ambient temperature, rather than in vitro or at harsh film‐forming conditions. (Lv et al, ; Wang, Liu, et al, ; Zhao et al, ) It could be potentially used as the base materials for dermatological drug carrier, wearable electronic skin, and wounding dress.…”

“…Among the synthetic materials, silicone elastomers are particularly focused due to their outstanding properties (Borde et al, ; Rutnakornpituk, Ngamdee, & Phinyocheep, ; Zou et al, ) such as low toxicity, good biocompatibility, physiological inertness, excellent thermal and oxidative stability, unique esthetic properties, and so forth. Zhang and co‐workers (Wang et al, ) fabricated a smart elastomer skin with extreme hydrophobicity, excellent skin conformability, and reversible deformation capabilities by employing laser engraving technique on the deformable poly (dimethyl siloxane) (PDMS) elastomer that was prepared by mixing Sylgard 184 (Dow Corning) and curing agent and further curing at 85°C for 1 hr. Zhao and co‐workers (Zhao, Xu, Luo, Wu, & Xia, ) prepared a remoldable polysiloxane elastomer with excellent self‐healing ability by cross‐linking of PDMS bearing maleimide pendants with furan‐end siloxane and claimed their application as artificial skin and scaffolds for tissue engineering.…”

Etching-assisted femtosecond laser modification of hard materials

“…In recent decades, femtosecond laser direct writing (FsLDW) has demonstrated to be a high precision processing method that can be used for 3D micro/nanofabrication of almost any materials. With these advantages, the technology has exhibited great potential applications in micro-optics, microelectronics, micro-mechanics, microfluidics, micro-optoelectronics, sensing, bionics and biomanufacturing [3][4][5][6][7][8][9][10][11][12][13][14] . Femtosecond laser direct writing technology can be divided into two categories: additive manufacturing and subtractive manufacturing.…”