Superamphiphobic, Magnetic, and Elastic Silicone Sponges with Excellent Temperature Stability

Abstract

separation, drug delivery, sensor and catalysis, etc. [2] With the fast development of superhydrophobic surfaces, many superhydrophobic 3D-PMs including sponges, foams and aerogels with excellent properties have been created by combining appropriate surface roughness and materials with low surface energy. [3] A variety of methods, such as 3D printing, [1c] dip-coating, [3b] template method, [4] and sol-gel method, [5] have been used to prepare superhydrophobic 3D-PMs. Lee et al. prepared superhydrophobic 3D-PMs by coating polyurethane sponges with conjugated microporous polymers. [3b] The superhydrophobic 3D-PMs show good selectivity, fast adsorption kinetics, excellent recyclability, and absorbencies for a wide range of organic solvents and oils, which make them the promising candidates for liquid-liquid separation and water treatment. We have prepared many kinds of superhydrophobic 3D-PMs by polymerization of organosilanes and polydimethylsiloxane (PDMS), [6] and by coating polyurethane sponges and carbon aerogels with polysiloxanes and PDMS. [7] Guo and co-workers reviewed the recent progress about the applications of superhydrophobic 3D-PMs for oil/water separation. [8] Greiner and co-workers reported preparation of conductive and superhydrophobic 3D-PMs by efficient wet-chemical metallization, which could be highly interesting for heating and insulation devices. [9] However, superhydrophobic 3D-PMs can still be easily wetted by organic liquids of low surface tension. It remains a great challenge to create superamphiphobic 3D-PMs that resist wetting of organic liquids because of their low surface tension (for example, 27.5 mN m −1 for n-hexadecane compared to 72.8 mN m −1 for water). As far as we know, there are few reports on superamphiphobic 3D-PMs. Zhao and co-workers developed superamphiphobic 3D-PMs that turns superhydrophilic and superoleophobic upon ammonia exposure. [10] Kanamori and co-workers fabricated superamphiphobic silicone monoliths by the sol-gel reaction of organosilanes with vinyl groups and subsequent attachment of perfluoroalkyl groups to the vinyl groups by the thiolene click reaction. [11] Nevertheless, 95%-97% of the vinyl groups remain unreacted, which results in oxidation of the monolith and decline of the superamphiphobicity at temperature above 170 °C. In addition, superamphiphobicity of the monolith is quite common with It is very challenging to create bioinspired superamphiphobic 3D porous materials that resist wetting of organic liquids with low surface tension. Here, preparation of superamphiphobic, magnetic, and elastic (SAME) silicone sponges is reported with excellent temperature stability. The SAME silicone sponges are prepared by hydrolytic condensation of methyltrimethoxysilane and dimethoxydimethylsilane in the presence of urea, n-hexadecyltrimethyl ammonium bromide, and the Fe 3 O 4 @SiO 2 nanoparticles, followed by surface modification with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) and tetraethoxysilane (TEOS). The SAME silicone sponges are characteriz...

Switchable and Reversible Superhydrophobic Surfaces: Part Two

“…The sponges were also superhydrophobic and superoleophilic, quickly absorbed floating oils on the water surface and also displayed high mechanical properties. Other materials were also used in the literature [29][30][31][32][33][34][35]. Inspired by marine mussel adhesive, Jiang et al used dopamine to link Fe 3 O 4 nanoparticles on electrospun PVDF [29].…”

“…Zhang et al reported superamphiphobic elastic and magnetic silicone sponges with excellent thermal stability [31]. Their sponges were prepared by hydrolytic condensation of methyltrimethoxysilane, dimethoxydimethylsilane in the presence of Fe 3 O 4 @SiO 2 nanoparticles and finally fluorinated.…”

“…Using magnetically responsive mesh substrates, micro-robots were fabricated (Figure 4) [30]. The meshes could float and move on air/water and oil/water interfaces and could be guided by a magnetic field.Zhang et al reported superamphiphobic elastic and magnetic silicone sponges with excellent thermal stability [31]. Their sponges were prepared by hydrolytic condensation of methyltrimethoxysilane, dimethoxydimethylsilane in the presence of Fe 3 O 4 @SiO 2 nanoparticles and finally fluorinated.…”

Fabrication of durable super-repellent surfaces on cotton fabric with liquids of varying surface tension: Low surface energy and high roughness

“…In order to fabricate superhydrophobic surfaces, addition of various nanoparticles such as silver, SiO2, TiO2, Fe3O4, ZrO2 in combination with low surface energy materials such as fluorinated compounds and polymers have been reported in literature [15][16][17][18][19].…”

A free-standing porous silicon-type gel sponge with superhydrophobicity and oleophobicity

“…[17][18][19][20][21] Moreover, if the amphiphobicity is sustained throughout the whole monolith material volume, it can foster formation of fresh re-entrant surface with amphiphobic property aer removed of the uppermost damaged layer. 22,23 In our previous work, we fabricated superhydrophobic elastic silicone rubber with excellent mechanical durability and showed the superhydrophobicity when exposed to harsh environments such as strong corrosion, extremely low temperature, various external damages, especially high mechanical stress. 24 In this work, we present a template-free procedure for the fabrication of marshmallow-like silicon monoliths with superhydrophobic and oleophobic properties.…”