Reversibly Thermosecreting Organogels with Switchable Lubrication and Anti‐Icing Performance

Abstract

Synthetic gels with switchable interfacial properties have great potential in smart devices and controllable transport. Herein, we design an organogel by incorporating a binary liquid mixture with an upper critical solution temperature (UCST) into a polymer network, resulting in reversible modulation of lubrication and adhesion properties. As the temperature changes, the lubricating mechanism changes reversibly from boundary lubrication to hydrodynamic lubrication due to phase separation within the binary solution permeating the gel (friction coefficient 0.4-0.03). Droplets appear on the gel surface at low temperature and disappear with temperature higher than the critical phase separation temperature (T ps) of the organogel. The organogel possesses a relatively low ice adhesive strength (less than 1 kPa). This material has potential applications in anti-icing and smart devices, and we believe that this design strategy can be expanded to other systems such as aqueous solutions and hydrogels.

Dense Hydrogen-Bonding Network Boosts Ionic Conductive Hydrogels with Extremely High Toughness, Rapid Self-Recovery, and Autonomous Adhesion for Human-Motion Detection

“…Figure S9a depicted that the resistance values gradually decreased as temperature increased from 25 to 70°C, which was consistent with the results of the varied ionic conductivity as the temperature increased. Besides, the PAM-r-MVIC-2 exhibited a promising ionic conductivity even at an extremely low temperature (Figure S9b ), attributed to a reduced freezing point of hydrogels by the introduction of PIL backbones [ 40 – 43 ]. The sensing performance over a wide temperature range (-20~80°C) was illustrated ( Figure 6(b) ).…”

Dynamic Anti‐Icing Surfaces (DAIS)

“…Many anti-icing surfaces use dynamic substrates that respond to the ambient conditions of temperature, magnetic field, light, and so on. [36,44,[73][74][75][76][77][78][79][80][81] By integrating temperature sensitive com-ponents during fabrication, anti-icing substrates can respond to temperature change in the surrounding. [44,73] One of such substrates incorporated a binary liquid mixture (silicon oil and liquid paraffin) into a PDMS network, and the resulting reversibly thermosecreting organogel (RTS-organogel) demonstrated distinct The thermal responsive lubricant regenerable organogel, showing the droplets secretion at low temperature and reversible droplets absorption at high temperature.…”

Anisotropic Protein Organofibers Encoded With Extraordinary Mechanical Behavior for Cellular Mechanobiology Applications

“…Engineered hydrogels and gel‐derived fibers are nascent and appealing soft matters, particularly in contexts of advanced wearables, [1–2] electronic devices, [3–5] drug delivery, [6] cosmetics, [7] food technology, [8] and smart behavior system, [9] due to their high stretchability, flexibility, hybrid networks, and diverse functionalities. However, those gel fibers show inferior mechanical properties, such as low fracture toughness, modulus, and strength (Table 1).…”