One‐Step Fabrication of Universal Slippery Lubricated Surfaces

Abstract

lubricant on the LIS is a fluid, substrates for the LIS should possess a porous or textured structure to induce the capillary force that retains the lubricant layer. In addition, the substrate must have a hydrophobic surface with a low surface energy to achieve a stable lubricant layer; the low surface energy is crucial since the total interfacial energy among substrate, liquid drop, and lubricant should be lower than that between substrate and liquid drop for effective repulsion of the liquid drops. [14,15] In line with the above requirements, numerous engineering technologies have been explored to fabricate slippery LISs. [16-18] However, their porous/textured structure results in weakened mechanical properties, thereby restricting fabrication to limited structures and materials. There has been some progress toward producing slippery surfaces on flat or nontextured surfaces. Recently, a stable lubricant-impregnated surface on a smooth substrate was introduced with the aid of π-electron interactions between the surface-modifying molecules and lubricant. [19] On this surface, phenolic groups were grafted onto the substrate, following which oleic acid was infused. The attractive interaction of the-OH group in oleic acid and π-electrons in the phenolic group increased the stability of the infused oleic acid on the surfaces, providing durability in extreme environments. [20] Even though this slippery surface does not require a porous or textured structure, the surface modification relies on the speci fic chemical interactions. This highly specific nature is a roadblock for the application of this method to other materials. A photo catalytically active lubricant-impregnated surface (PALIS) is a viable alternative for flat or nontextured slippery surfaces because the hydrophobized metal-oxide surface with a polydimethylsiloxane (PDMS) brush helps to form a stable PDMS lubricant layer. [21] However, the PALIS can only be prepared on a metal-oxide photocatalyst under UV light. [22,23] Most recently, a surface functionalization method to coat flat surfaces with PDMS brushes, followed by silicone oil infusion, was reported. To generate the PDMS brush, the surface was first treated with 1,3,5,7-tetramethylcyclotetrasiloxane, then immersed into a vinyl-terminated PDMS solution with a catalyst to graft PDMS by the hydrosilylation reaction. [24] Though the surface exhibited good liquid repellency, the reaction, including the pretreatments, was complicated and cumbersome.

Substrate‐Independent Design of Liquid‐Infused Slippery Surfaces via Mussel‐Inspired Chemistry

“…A second approach to create LISs are polymer brushes that are bound to a solid surface. [ 21,22,29–34 ] Typically, alkylsiloxanes such as polydimethylsiloxane (PDMS) brushes are used to provide a liquid‐like, low surface energy surface. The liquid‐like molecule chains can be coupled via silane chemistry, [ 32 ] via π‐electron interactions after surface silanization, [ 33 ] from acidic sol–gel chemistry [ 21,29 ] or by partial thermal decomposition.…”

Super pressure-resistant superhydrophobic fabrics with real self-cleaning performance

“…The C 1s peak is composed of CF 3 (293.8 eV), CF 2 (292.4 eV), C-O/C-OH (286.5 eV), and C-C/C-H/C-Si (284.8 eV) peaks ( Figure 1 I). The Si 2p peak is composed of Si-C (102.0 eV), Si-O (103.3 eV) and Si- O -Si (103.9 eV) peaks ( Figure S4 ) ( Chen et al., 2020 ; Qing et al., 2020 ). The F content reaches 37.84 at%, indicating presence of abundant perfluorodecyl groups on the surface of the fabric ( Li et al., 2019a ).…”

Universal Large-Scale and Solvent-Free Surface Modification of Inorganic Particles via Facile Mechanical Grinding

“…The surface of nano/microparticles can be modified by attaching various organics with linking groups. − The linking group of the organic forms a bond with the surface, whereas the other part of the molecule defines the surface property. − Polysiloxanes (PSOs), which are polymers based on siloxane backbones, are promising materials for modifying the particle surfaces. − Due to the stable siloxane bond with relatively high bonding energy (444 kJ mol –1 ), the PSOs exhibit good chemical and thermal stabilities and biocompatibility. − In addition, the PSOs can be decomposed by hydrolysis in soil, allowing more eco-friendly and sustainable chemistry . Recently, it was shown that the hydrosilylation reaction can be used to graft PSOs onto the surface of oxides. − The siloxane backbone is cleaved in the presence of hydroxyl groups and subsequently grafted to the hydroxyl groups on the surface of oxides, forming a PSO brush of a few nanometers in thickness. The PSO brush grafting reaction has also been applied to modify the surfaces of metal oxides having surface hydroxyl groups, resulting in the formation of various functional surfaces, such as hydrophobic photocatalysts, , stable lubricant impregnated surfaces, ,, and a blood repelling dress .…”