One-Step Synthesis of Dynamically Shaped Stiff Nanorods Using Soft Silicone Materials to Control Water Repulsion and Collection

One-dimensional silicone nanostructures, such as filaments, wires, and tubes, have attracted significant attention, owing to their remarkable application capabilities in a large range of material and surface science. However, the soft mechanical properties of silicone cause vulnerability and irregularity in the synthesized structures, which limits their applications. Herein, a simple, solvent-free, and efficient dynamic Droplet Assisted Growth and Shaping (d-DAGS) strategy is proposed for the one-step synthesis and in situ control of the shape of silicone nanostructures. The special designed bamboo-shaped silicone nanorods (SNRs) that are produced by the repetitive dynamic regulation of growth conditions, concomitant with the periodic purging and injection of precursors, exhibit highly-regular and tunable structure with a specific number of segments, indicating that they can be tailor-made according to the requirements of various properties. The enhanced mechanical stiffness and chemical durability strongly support their excellent performances in water-resistance under both static and dynamic wetting conditions. The SNRs significantly promote buoyancy and self-cleaning properties; and exhibit very high water-harvesting efficiency compared with existing designs. Notably, the well-structured ultra-long rods with an ultrahigh aspect ratio (≈176) can also be fabricated by the d-DAGS method, and they can remain standing straight upwards and regular, even though they consist of flexible silicone

Silicone Nanofilament Coatings as Flexible Catalyst Supports for a Knoevenagel Condensation Reaction in Batch and Flow Systems

In this work, silicone nanofilament (SNF) coatings were prepared via a droplet-assisted growth and shaping (DAGS) approach, where the preparation of the coatings is allowed under ambient conditions. The application of SNF coatings as catalyst supports for amino moieties from (3-aminopropyl)triethoxysilane (APTES) was investigated. With the optimized coating conditions identified, the Brunauer–Emmett–Teller surface areas of a bare glass filter substrate and bare glass beads after the coating have increased by 5-fold and 16-fold, respectively. The SNF-coated filters were readily functionalized with amino groups via a liquid-phase deposition process, and their catalytic activities for a Knoevenagel reaction were evaluated using a batch reactor and a packed bed reactor. In both reactors, the as-prepared filters demonstrated superior catalytic performance over the functionalized filters without SNF coatings. Notably, the unique flexibility of the SNF coatings allowed the facile preparation of a packed bed reactor and a scalable catalytic system. It is expected that the packed bed system established in this study will support the development and the use of various SNF-supported organocatalysts and catalytic materials

Printable and Versatile Superhydrophobic Paper via Scalable Nonsolvent Armor Strategy

Despite great scientific and industrial interest in waterproof cellulosic paper, its real world application is hindered by complicated and costly fabrication processes, limitations in scale-up production, and use of organic solvents. Furthermore, simultaneously achieving nonwetting properties and printability on paper surfaces still remains a technical and chemical challenge. Herein, we demonstrate a nonsolvent strategy for scalable and fast fabrication of waterproofing paper through in situ surface engineering with polysilsesquioxane nanorods (PSNR). Excellent superhydrophobicity is attained on the functionalized paper surface with water contact angle above 160˚. Notably, the engineered paper features outstanding printability and writability, as well as greatly enhanced strength and integrity upon prolonged exposure to water (tensile strength ≈ 9.0 MPa). Additionally, the PSNR concurrently armors paper-based printed items and artwork with waterproofing, self-cleaning and antimicrobial functionalities without compromising their appearance, readability and mechanical properties. We also demonstrate that the engineered paper holds the additional advantages of easy processing, low cost and mechanochemical robustness, which makes it particularly promising for real world applications

Size-Dependent Submerging of Nanoparticles in Polymer Melts:Effect of Line Tension

Adhesion of nanoparticles to polymer films plays a key role in various polymer technologies. Here we report experiments that reveal how silica nanoparticles adhere to a viscoelastic PMMA film above the glass transition temperature. The polymer was swollen with CO₂, closely matching the conditions of nanoparticle-nucleated polymer foaming. It is found that the degree by which the particles sink into the viscoelastic substrate is strongly size dependent and can even lead to complete engulfment for particles of diameter below 12 nm. These findings are explained quantitatively by a thermodynamic analysis, combining elasticity, capillary adhesion, and line tension. We argue that line tension, here proposed for the first time in elastic media, is responsible for the nanoparticle engulfment

In vitro and in vivo antiviral activity of monolaurin against Seneca Valley virus

IntroductionSurveillance of the Seneca Valley virus (SVV) shows a disproportionately higher incidence on Chinese pig farms. Currently, there are no vaccines or drugs to treat SVV infection effectively and effective treatment options are urgently needed.MethodsIn this study, we evaluated the antiviral activity of the following medium-chain fatty acids (MCFAs) or triglycerides (MCTs) against SVV: caprylic acid, caprylic monoglyceride, capric monoglyceride, and monolaurin.ResultsIn vitro experiments showed that monolaurin inhibited viral replication by up to 80%, while in vivo studies showed that monolaurin reduced clinical manifestations, viral load, and organ damage in SVV-infected piglets. Monolaurin significantly reduced the release of inflammatory cytokines and promoted the release of interferon-γ, which enhanced the viral clearance activity of this type of MCFA.DiscussionTherefore, monolaurin is a potentially effective candidate for the treatment of SVV infection in pigs

Solvent-Free Fabrication of Flexible and Robust Superhydrophobic Composite Films with Hierarchical Micro/Nanostructures and Durable Self-Cleaning Functionality

Superhydrophobic surfaces hold tremendous potential in a wide range of applications owing to their multifaced functionalities. However, the mechanochemical susceptibility of such materials hinders their widespread usage in practical applications. Here, we present a simple, solvent-free, and environmentally friendly approach to fabricate flexible and robust superhydrophobic composite films with durable self-cleaning functionality. The obtained composite film features unexpected but surprising hierarchical micro/nanoscopic structures as well as robust superhydrophobicity with a water contact angle of similar to 170 degrees and a sliding angle below 4 degrees. Notably, the composite film exhibits mechanical robustness under cyclic abrasion, tape peeling, flexing, intensive finger wiping, and knife cutting; maintains excellent superhydrophobicity after long-time exposure to a high-humidity environment; and sustains exposure to highly corrosive species, such as strong acid/base solutions and organic solvents. The robust superhydrophobicity is ascribed to the induced micro/ nanohierarchical surface structures, resulting in the trapped dual-scale air pockets, which could largely reduce the solid/liquid interface. In addition, even after oil contamination, the composite film water repellency and self-cleaning functionality. The robust superhydrophobic composite film developed here is expected extend the application scope of superhydrophobic materials and should find potential usage in various industries and daily life

Hierarchical Structured Multifunctional Self‐Cleaning Material with Durable Superhydrophobicity and Photocatalytic Functionalities

Self-cleaning materials, which are inspired and derived from natural phenomena, have gained significant scientific and commercial interest in the past decades as they are energy- and labor-saving and environmentally friendly. Several technologies are developed to obtain self-cleaning materials. The combination of superhydrophobic and photocatalytic properties enables the efficient removal of solid particles and organic contaminations, which could reduce or damage the superhydrophobicity. However, the fragility of the nanoscale roughness of the superhydrophobic surface limits its practical application. Here, a hierarchical structure approach combining micro- and nanoscale architectures is created to protect the nanoscale surface roughness from mechanical damage. Glass beads of 75 mu m are partially embedded into a low-density polyethylene film. This composite surface is coated with silicone nanofilaments (SNFs) via the droplet-assisted growth and shaping approach, providing the nanoscale surface roughness as well as the support for the photocatalyst with enlarged surface area. TiO2 nanoparticles, which serve as the photocatalyst, are synthesized in situ on SNFs through a hydrothermal reaction. The self-cleaning effect is proved using wettability measurements for various liquids, degradation of organic contamination under UV light, and antibacterial tests. The enhanced mechanical durability of the hierarchical structure of the composite material is verified with an abrasion test

Tunable bulk material with robust and renewable superhydrophobicity designed via in-situ loading of surface-wrinkled microparticles

Superhydrophobic surfaces possess susceptibility towards mechanical and chemical damages as well as oil fouling, which limits their widespread use in practical applications. Here, we demonstrate a straightforward approach to fabricate tunable bulk material with robust and renewable superhydrophobicity by in-situ loading of interconnected surface-wrinkled microparticles. The bulk material shows mechanochemically robust superhydrophobicity across its whole 3D volume, features renewable superhydrophobicity after extremely chemical corrosion, and could regenerate its water repellency after oil contamination. The bulk material also features ultrahigh efficiency (~98%) in oil-water mixtures separation, due to its selective oil absorption capability from water. Notably, the mechanical performances, microstructures and density of the bulk material can be adjusted on demand by simply changing the amount of loaded microparticles. Compared to the pristine commercial melamine-formaldehyde based porous substrate (MFPS), the achieved bulk material shows up to ~230 folds increase in Young’s modulus, ~145 folds increase in flexure stress and ~25 folds increase in tensile stress. This strategy features great potential for designing lightweight structural materials with robust waterproof functionality as well as materials with efficient oil recovery capability from wastewater