Rinse-resistant superhydrophobic block copolymer fabrics by electrospinning, electrospraying and thermally-induced self-assembly

Abstract

An inherent problem that restricts the practical application of superhydrophobic materials is that the superhydrophobic property is not sustainable; it can be diminished, or even lost, when the surface is physically damaged. In this work, we present an efficient approach for the fabrication of superhydrophobic fibrous fabrics with great rinse-resistance where a block copolymer has been electrospun into a nanofibrous mesh while micro-sized beads have been subsequently electrosprayed to give a morphologically composite material. The intricate nanoand microstructure of the composite was then fixed by thermally annealing the block copolymer to induce self-assembly and interdigitation of the microphase separated domains. To demonstrate this approach, a polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) nanofibrous scaffold was produced by electrospinning before SEBS beads were electrosprayed into this mesh to form a hierarchical micro/nanostructure of beads and fibers. The effects of type and density of SEBS beads on the surface morphology and wetting properties of composite membranes were studied extensively. Compared with a neat SEBS fibrous mesh, the composite membrane had enhanced hydrophobic properties. The static water contact angle increased from 139° (±3°) to 156° (±1°), while the sliding angle decreased to 8° (±1°) from nearly 90°. In order to increase the rinse-resistance of the composite membrane, a thermal annealing step was applied to physically bind the fibers and beads. Importantly, after 200 hours of water flushing, the hierarchical surface structure and superhydrophobicity of the composite membrane were well retained. This work provides a new route for the creation of superhydrophobic fabrics with potential in self-cleaning applications.

Superhydrophobic Bilayer Coating Based on Annealed Electrospun Ultrathin Poly(ε-caprolactone) Fibers and Electrosprayed Nanostructured Silica Microparticles for Easy Emptying Packaging Applications

“…Superhydrophobic coatings present surfaces with water contact angles larger than 150 • and sliding angles of less than 5 • [1]. They have gained popularity over the last few decades to improve the current capabilities of material surfaces for applications in water repellency, self-cleaning, packaging, etc.…”

“…To achieve superhydrophobicity on synthetic surfaces, the chemical and physical compositions of the surface at both the micro-and nanoscales must be efficiently designed. Various superhydrophobic surface coatings have been recently prepared by either modifying the chemistry of the surface to render hydrophobic properties [5,6] or by creating nanometer-scale features on micro-roughened surfaces using different techniques, such as plasma treatment, chemical etching, layer-by-layer (LbL) deposition, chemical vapor deposition (CVD), micropatterning by lithography, and, more recently, electrohydrodynamic processing (EHDP) [1,4,7].…”

“…Alternatively, the use of EHDP for both electrospinning and electrospraying processes, has proven to be a straightforward methodology for manufacturing micro-and nanoscale structures from a wide variety of polymer materials in a flexible and controlled manner [8]. Such techniques can particularly allow the fabrication of different polymer-based structures and assemblies in the packaging field [9], in which some of them can additionally display a high degree of complexity in terms of surface morphology and topology [1].…”

Improving waterproof/breathable performance of electrospun poly(vinylidene fluoride) fibrous membranes by thermo‐pressing

“…To overcome this problem, some strategies comprising surface modification, polymer blending, thermal post‐treatment, and sheath/core fiber structure have been adopted to enhance the mechanical properties of these electrospun membranes. Among them, surface modification and thermal post‐treatment have been also proposed to improve waterproof/breathable performance .…”

Effect of different treatments and SiO2/PVDF coatings on morphology and wettability of electrospun polyamide 6 membranes

“…fabricated the triblock copolymer fibers by electrospinning, and then deposited the triblock copolymer beads on the fibers by electrospraying. In order to fix the beads on the fibers, thermally annealing was used to induce self‐assembly and physical crosslink, which can improve the stability of superhydrophobic surface . Ma et al .…”