Abrasion Cycles Research Articles

Enhancing durability of concrete mixtures with supplementary cementitious materials: A study on organic acid corrosion and physical abrasion in pig farm environments

This study assessed concrete durability in pig farm environments, focusing on resistance to organic acid corrosion and physical abrasion. It used supplementary cementitious materials like silica fume (SF), coal fly ash (CFA), and bagasse fly ash (BFA) to improve concrete resilience. The research involved casting and testing concrete samples for compressive strength, acid corrosion resistance, abrasion resistance, and their combined effects. A custom apparatus simulated corrosion and abrasion cycles typical in pig farm flooring. Results showed that a combination of SF, CFA, and BFA significantly enhanced compressive strength, especially with extended curing. Additionally, these materials improved concrete's resistance to acid corrosion, physical abrasion, and their combined effects. The replacement of 30 wt% of cement with CFA and BFA in concrete significantly reduced mass loss due to acid corrosion to less than 10%, whereas the control mix exhibited a mass loss exceeding 24%. Additionally, concrete with 30 wt% CFA or BFA replacement exhibited a minimal combined mass loss, decreasing to less than 2.5% due to acid corrosion and physical abrasion, as opposed to the 16% observed in the control mixture.

Is the whitening effect of charcoal-based dentifrices related to their abrasive potential or the ability of charcoal to adsorb dyes?

ObjectivesTo evaluate if tooth color alteration of activated charcoal-based dentifrices may be attributed to the dye adsorption potential of charcoal (chemical action - C - slurry only) or to the association of dye adsorption with abrasion (chemo-mechanical action - CM- slurry/toothbrushing). Potential adverse effects in surface roughness, gloss, and wear were also assessed. MethodsBovine enamel/dentin specimens were randomly allocated into the groups according to treatments and test model (n = 15): deionized water (negative control- NC); Colgate Maximum Anticaries Protection (conventional toothpaste- positive control- PC); Colgate Luminous White Activated Charcoal (LW); Oral-B 3D White Therapy Charcoal (WT); Curaprox Black is White (BW); Dermavita Whitemax (Activated charcoal powder- WP). Specimens were exposed to the C or CM models, in 28-day staining-treatment cycling. Color change (ΔE00), whiteness index (ΔWID), percentage of alteration of surface roughness (%Raalt), and gloss (%GUalt) were calculated. Additional specimens (n = 9) were indented with a Knoop diamond and subjected to 100,000 abrasion cycles. Enamel wear was determined by calculating the decrease in indentations geometry. Data were analyzed by ANOVA/Tukey tests (α = 0.05). ResultsThe CM-model produced lower color change (staining) than C (p = 0.0001). PC, LW, WT, BW, and WP showed similar color results for both models, differing from NC (p < 0.05).%Ra and%GU did not differ among the C-model groups (p > 0.05) and WP exhibited the highest variation (%Ra and%GU) under CM-model. Enamel wear values were lowest in the NC and PC groups, intermediate for LW, WT, BW, and highest for the WP (p < 0.05). ConclusionActivated charcoal-based dentifrices have a similar ability to minimize tooth staining as the conventional toothpaste, with increased enamel wear potential in the long term (after 100,000 cycles). The activated charcoal powder damaged the enamel surface, showing a higher deleterious effect on enamel roughness, gloss, and wear. Clinical significanceDentifrices containing activated charcoal do not provide superior results to minimize tooth staining compared to conventional toothpaste. Charcoal powder should be used with caution because it promotes higher superficial alterations on the enamel surface.

Anti-abrasion collagen fiber-based membrane functionalized by UiO-66-NH2 with ultra-high efficiency and stability for oil-in-water emulsions separation

Membrane separation strategies offer promising platform for the emulsion separation. However, the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant challenges. In this study, we report a CFM@UiO-66-NH2 membrane with high separation flux, efficiency and stability, through utilizing a robust anti-abrasion collagen fiber membrane (CFM) as the multifunctional support and UiO-66-NH2 by an in-situ growth as the separation layer. The high mechanical strength of the CFM compensated for the weakness of the separation layer, while the charge-breaking effect of UiO-66-NH2, along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers, contributed to the potential for efficient separation. Additionally, the CFM@UiO-66-NH2 membrane exhibited superhydrophilic properties, making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic surfactants. The membrane demonstrated remarkable separation efficiencies of up to 99.960% and a separation flux of 370.05 L·m−2·h−1. Moreover, it exhibits stability, durability, and abrasion resistance, maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and performance. After six cycles of reuse, it achieved a separation flux of 417.97 L·m−2·h−1 and a separation efficiency of 99.747%. Furthermore, after undergoing 500 cycles of strong abrasion, the separation flux remained at 124.39 L·m−2·h−1, with a separation efficiency of 99.992%. These properties make it suitable for the long-term use in harsh operating environments. We attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH2 and its in-situ growth on the CFM, which forms a size-screening separation layer. Our work highlights the potential of the CFM@UiO-66-NH2 membrane as an environmentally friendly size-screening material for the efficient emulsion wastewater separation.

Robust polyurea icephobic coatings with static large-scale de-icing and dynamic anti-icing performance

Ice accumulation significantly affects the operation of infrastructure and the safety of transportation. Passive icephobic materials utilize inherent properties to achieve anti-icing performance, which has the benefits of no energy consumption and environmental protection. However, their degraded robustness in harsh environments severely limits practical applications. It is still a challenge to prepare icephobic materials that maintain both icephobicity and robustness. In this study, we propose a rational strategy for revolutionarily achieving both icephobicity and robustness by adopting a combination of soft and hard segments impregnated with the lubricant agent. Based on the strategy, the polyurea icephobic coating (PUIC) developed by the NCO-terminated prepolymer, polyaspartic ester, and dimethyl silicone oil ensures rapid and nondamaging ice detachment on the interface (low ice adhesion strength ∼23.7 kPa) via the synergistic effects of hydrophobicity, elastic deformation, and interfacial slippage. In addition, the resulting PUIC can reserve icephobicity under not only continuous 5000 Taber abrasion cycles before the complete wearing off the coating, but also 50 icing/de-icing cycles, 72 h acid/alkali immersion, 72 h UV radiation, and 240 h neutral salt spray. Furthermore, the destroyed PUICs can be recovered by organic solvents and maintain excellent icephobicity. Together with icephobicity, robustness, and scalability, PUICs are effective in static large-scale de-icing and dynamic anti-icing, with broad prospects in practical applications.

Phyllostachys Viridis-Leaf-like MLMN Surfaces Constructed by Nanosecond Laser Hybridization for Superhydrophobic Antifogging and Anti-Icing.

In nature, many species commonly evolve specific functional surfaces to withstand harsh external environments. In particular, structured wettability of surfaces has attracted tremendous interest due to its great potential in antifogging and anti-icing properties. Phyllostachys Viridis is a resistant low-temperature (-18 °C) plant with superhydrophobicity and ice resistivity behaviors. In this work, with inspiration from the representative cold-tolerant plants leaves, a unique multilevel micronano (MLMN) surface was fabricated on copper substrate by ultrafast laser process, which exhibited superior superhydrophobic characteristics with the water contact angle > 165° and rolling angle< 2°. In the dynamic wettability experiment, the rebound efficiency of the droplet on the MLMN surface reached 20.6%, and the contact time was only 10.6 ms. In the condensation experiment, the nucleation, growth, merging, and bouncing of fog drops on the surface was distinctly observed, indicating that rational texture structures can improve the antifogging performance of the surface. In the anti-icing experiment, the freezing time was delayed to 921 s at -10 °C, and the freezing time of salt water reached a staggering 1214 s. Moreover, the mechanical durability of MLMN surfaces was confirmed by scratch damage, sandpaper abrasion, and icing and melting cycle tests, and their repairability was evaluated for product applications in practice. Finally, the underlying antifogging/anti-icing strategy of the MLMN surface was also revealed. We anticipate that the investigations offer a promising way to handily design and fabricate multiscale hierarchical structures with reliable antifogging and anti-icing performance, especially in saltwater-related applications.

Durable water- and oil-repellent textiles without long- or short-chain perfluoroalkylated substances

For decades, the water and oil repellency of textiles was achieved using long-chain (CnF2n+1, n ≥ 7) perfluoroalkyl substances (PFAS). However, due to their proven bioaccumulative nature and toxic impacts on the environment and human health, these substances have been phased out of industrial production and/or legally banned in many countries. There is some evidence that a shorter carbon chain leads to less bioaccumulation and toxicity, and accordingly short-chain PFAS have been widely used as a replacement in recent years. Nevertheless, short-chain PFAS exhibit inferior surface properties due to their less crystalline and more loosely packed polymer chains, as compared to their long-chain counterparts. Moreover, surface properties become worse with decreasing chain length. Here we develop an alternative method for obtaining durable water and oil repellency on a nylon fabric using a liquidlike perfluoropolyether (PFPE) brush coating. The coating demonstrates excellent water and oil repellency, on par with the banned long-chain PFAS finishes, although its longest PFAS degradation product would have a chain length of L = 3, i.e. an ultra-short-chain PFAS. The PFPE-treated nylon exhibits superior surface properties compared to state-of-the-art, short-chain PFAS finished fabrics used in industry currently, even after laundering and 10,000 cycles of abrasion. The comfort of the treated fabrics is also maintained. The PFPE coatings developed here could replace the toxic, short-chain PFAS in use worldwide today.

MIL-88A-based Antifouling Superhydrophilic Membrane for Efficient Emulsion Separation and Dye Degradation via Photo-Fenton Process

Pollution of oily wastewater is a serious worldwide environmental problem that causes serious harm to the environment and human beings, while at the same time, emulsifier and dye wastewaters pose great difficulties for wastewater treatment. In a previous study, MIL-88A as an iron-based metal-organic frameworks (MOFs) has good hydrophilicity and large specific surface area, in addition, it acts as a Fenton catalyst, generating strong oxidizing hydroxyl radicals under the condition of UV light and hydrogen peroxide to achieve efficient degradation of dyes. Inspired by this, we prepared nano-needle zinc oxide on stainless steel mesh (SSM) by electrochemical method, and then prepared MIL-88A-based superhydrophilic membranes by spraying method, which can easily separate a variety of oil-in-water emulsions. After 10 emulsion separations, the separation efficiency of the prepared membrane was still as high as 99.5 %. In addition, the prepared membranes have a high removal rate of methylene blue (MB), degrading 98 % of MB in 35 min, and remain underwater superoleophobic even after 50 cycles of sandpaper abrasion. This robust mesh for efficient emulsion separation and dye removal shows great potential for oily wastewater treatment and water quality remediation.

Scalable fabrication of a robust asymmetric superwetting Janus mesh by facile spray-coating for oil–water emulsions separation

Janus membrane with asymmetric wettability are emerging separation materials for the purification of emulsified oil–water mixtures, however, their poor mechanical durability and low-flux without external pressure severely limit their practical application. Herein, a robust superwetting Janus mesh demonstrating a high water contact angle (WCA) difference up to 157° was developed by simply spraying on the stainless steel mesh (SSM), via the superhydrophobic fluorocarbon resin/polyvinylidene fluoride/1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane modified titanium dioxide@carboxylated CNTs (FEVE/PVDF/F-TiO2@CNTs) layer and a superhydrophilic layer consisting epoxy resin/ethylene imine polymer/sodium perfluorooctanoate modified bentonite (EP/PEI/F-Bentonite). By carefully adjusting the surface polar-nonpolar molecule repulsion based on the two oppositely bond energy side and incorporating nano/microstructures to form a stable interfacial oiling/hydration layer, the robust Janus mesh achieved interface demulsification and gravity separation of emulsified oil–water mixtures. The prepared Janus SSM exhibited excellent gravity-driven separation performance, achieving a flux up to 1508.6 L m−2h−1 for water-in-oil (W/O) emulsions, and 843.1 L m−2h−1 for oil-in-water (O/W) emulsions. Additionally, it exhibited high separation efficiency with water rejection above 99.9 % and oil rejection above 99.7 %. Moreover, the prepared Janus mesh with fine uniform nano/microstructures and functionalized groups demonstrated notable reusability and mechanochemical stability after 10 cycles of O/W and W/O emulsion filtration, 100 cycles of sandpaper abrasion, and strong acid/alkali immersion for 7 d. Overall, this study expected to facilitate the fabrication of a robust asymmetric superwetting Janus mesh with enhanced separation properties for highly efficient oily wastewater treatment.

Programmable 3D bifurcated braided structures for system-adaptable and integrated triboelectric sensing

Textiles are a flexible framework for devising soft triboelectric nanogenerators (TENGs) that can monitor or harvest mechanical energy generated from body motion. Despite various structures and impressive performance, integrated textile TENGs that can regulate the contact-separation between triboelectric materials are rarely explored. Herein, we report a programmable three-dimensional (3D) braiding strategy to construct Y-profile bifurcated textile TENGs (3D Y-TENG) by the industry-compatible hexagonal braider. Through the regulation of interlaced and bifurcated regions along 3D Y-TENGs, different contact-separations can be obtained. 3D Y-TENGs were constructed by braiding two sets of core-sheath yarns with nylon and polytetrafluoroethylene (PTFE) as the triboelectric materials, with both yarns exhibiting exceptional abrasion resistance (i.e., 3000 cycles of abrasion without structural disintegration). Five 3D Y-TENG with different bifurcation patterns were designed and fabricated to tailor the contact-separation, all presenting triboelectric response towards mechanical compressing, stretching, and bending. 3D Y-TENGs are featured with remarkable stretchability, softness, flexibility, foldability, and mechanical endurance, enabling their comfortable contact with the human body. This work presents programmable braided structures that can be tailored, adapted, and integrated with different systems for seamless electronic garments.

Blood and bacterium repellent superhydrophobic coating based on assembly of nanoparticles

A new superhydrophobic coating with low surface roughness is prepared by facile spray-coating method for robust blood and bacterium repellent application. The superhydrophobic coating does not only display good water repellency with a large contact angle of 171.4°, but also shows a satisfactory mechanical stability (a contact angle of 151.8° after 100 abrasion cycles). Furthermore, the superhydrophobic coating is evaluated to apply in blood and bacterium repellency. It is observed that the blood droplet can roll off the surface within 0.5 s, and the bacteria count is reduced from 120 cfu/cm2 to 5.0 cfu/cm2. The good comprehensive performance is attributed to good superhydrophobicity and low surface roughness. This work thus provides a facile method to improve blood and bacterium repellent performance of superhydrophobic coating for biomedical application.

Fabrication of Superhydrophobic Coatings by Using Spraying and Analysis of Their Anti-Icing Properties

Ice accumulation on glass insulators is likely to cause faults such as flashover, tripping and power failure, which interfere with the normal operation of the power grid. Accordingly, superhydrophobic coatings with great anti-icing potential have received much attention. In this study, three superhydrophobic coatings (PTFE, Al2O3 and SiO2) were successfully prepared on glass surfaces by using one-step spraying. The microscopic morphology, wettability, anti-icing and anti-glaze icing properties of the superhydrophobic coatings were comparatively analyzed. The results indicated that the PTFE coating had a densely distributed rough structure, showing a contact angle of 165.5° and a sliding angle of 3.1°. The water droplets on the surface could rebound five times. Compared with the Al2O3 and SiO2 coatings, the anti-icing performance of the PTFE coating was significantly improved. The freezing time was far more than 16 times that of glass (4898.7 s), and the ice adhesion strength was 9 times lower than that of glass (27.5 kPa). The glaze icing test in the artificial climate chamber showed that the icing weight of the PTFE coating was 1.38 g, which was about 32% lower than that of the glass. In addition, the icing/melting and abrasion cycles destroyed the low-surface-energy substances and nanostructures on the surface, leading to the degradation of the anti-icing durability of the PTFE coatings. However, the PTFE coating still maintained excellent hydrophobicity and anti-icing properties after UV irradiation for up to 624 h. The superhydrophobic coatings prepared in this work have promising development prospects and offer experimental guidance for the application of anti-icing coatings on glass insulators.

Preparation of superhydrophobic coatings with excellent mechanical and chemical stability by one-step spraying method with selected fluorine-free modifiers

Superhydrophobic coatings have great potential for applications in daily life and industrial production. In practical applications, however, the excellent mechanical and chemical stability of superhydrophobic surfaces remains a challenge. In this paper, a one-step spraying method, simple in process and low cost, was used to prepare superhydrophobic materials. To investigate the effect of different types of non-fluorinated modifiers on the wettability of the coatings, four silane non-fluorinated modifiers, dodecyltrimethoxysilane, hetradecyltrimethoxysilane, octadecyltrimethoxysilane and polydimethylsiloxane, were selected to prepare superhydrophobic surfaces. The superhydrophobic coating modified by non-fluorinated modifier retained its superhydrophobic performance after 48 h immersion in strong acid, strong alkali and salt solution and 6 months in outdoor environment, with excellent corrosion resistance. Moreover, it showed superior abrasion resistance and durability in sandpaper abrasion and tape peeling cycles tests. The superhydrophobic coating prepared by PDMS had the best overall performance compared with other silane non-fluorinated modifiers, and the separation efficiency of the prepared superhydrophobic cotton fabric could still be maintained above 99 % after 20 oil–water separation cycles. Its water contact angle was 164.8° and sliding angle was 2.3°, and it had the highest first bouncing height after the droplet bouncing test.

UV-cured organic-inorganic hybrid networks for durable antifogging coating

Preventing surface fogging is critical for maintaining transparency in various transparent applications such as windows, mirrors and goggles. However, the fabrication of durable antifogging surfaces has been significantly challenging. The challenges include the lack of a simple preparation method, low coating hardness, poor water resistance and inability to self-healing. In this work, we developed an organic-inorganic interpenetrating hydrophilic antifogging coating using vinyl hybridized silica nanoparticles (VSNPs), polyvinyl alcohol (PVA), and methacrylic acid (MAA). A durable antifogging coating with self-healing capabilities has been prepared using a facile UV curing process. Such a hybrid coating can maintain its outstanding antifogging performance even after 4000 cycles of sand abrasion and 36 h of water immersion. Due to these outstanding properties and facile preparation, VSNPs-PVA/PMAA coating shows great potential in practical applications.

Preparation of robust silicone superhydrophobic and antibacterial textiles using the Pickering emulsion method

This study aimed to prepare textiles with superhydrophobic and antibacterial properties using the Pickering emulsion impregnation method. Cellulose nanocrystals were synergistically employed with dimethyloctadecyl[3-(trimethoxysilyl)-propyl] ammonium chloride as the solid surfactant, and hydrogenated (PHMS) and hydroxyl (MSDS) polysiloxane were used as the oil phase for emulsification. The emulsions were mixed and diluted in specific proportions, and the superhydrophobic and antibacterial textiles were prepared through fabric impregnation–drying strategies. The study optimised factors such as emulsion ratio and surfactant dosage. Results demonstrated that the nanoscale rough structure prepared using Pickering emulsion exhibited remarkable superhydrophobicity with contact and rolling angles of 163.1° ± 0.5° and 7.2° ± 0.2°, respectively. This effect was achieved when the ratio of PHMS emulsion to MSDS emulsion was maintained at 1:2 and the surfactant dosage was set at 2 %. The superhydrophobicity of textiles was maintained even after three washing cycles and 50 abrasion cycles, demonstrating excellent mechanical durability. The developed textiles also exhibited excellent oil/water separation ability, reliable recyclability and stability. Moreover, they demonstrated excellent self-cleaning and antibacterial capabilities. Thus, these valuable functionalities hold the potential to considerably improve the practical feasibility of superhydrophobic textiles in various application scenarios.

Neuron-like thermal silica bridge between boron nitride nanosheets with hard-soft composite structure to enhance thermal conductivity and anti-icing properties on CFRP

Carbon fiber reinforced polymer (CFRP) composites are popular as novel aeronautical material for its high strength and low density. However, CFRP is unfit for aircraft electric deicing system due to its low thermal conductivity and hydrophilicity, which leads to more serious icing phenomenon and inhibition of de-icing effect. Inspired by neuron structure, the thermal silica bridge in BNNS@SiO2 composite coatings were designed to improve the in-plane thermal conductive from 1.647 to 6.702 W/mK by sol–gel method and spraying technology. Hard SiO2 particles and soft boron nitride nanosheets (BNNS) constitute hard-soft composite structure with hydrophobicity, anti-icing properties (4.09 times icing delay time) and abrasion resistance (kept 98.7% after 180 abrasion cycles). Under the combined action of thermal conductivity and hydrophobicity, the 53.8% energy saving of de-icing system was realized under the heating power of 3 W. Meanwhile, the thermal conductive/hydrophobic composite coating both possessed insulation and flame retardant.

Thiol-ene click chemistry reaction for preparing superhydrophobic polyamide fabric with self-cleaning, UV-blocking, photothermal conversion and antibacterial properties

Polyphenols have been utilized to connect hydrophobic modifiers with certain substrates because of their adhesive properties and multiple active groups in their structure. Nevertheless, research is scarce regarding using polyphenols to enhance the superhydrophobic properties of polyamide. In this study, a plant-derived phenolic compound, p-coumaric acid (pCA), was chelated with Fe3+ and deposited on the polyamide 66 (PA66) surface to increase its roughness. Subsequently, octadecanethiol was grafted onto pCA using a thiol-ene click chemistry reaction to create a superhydrophobic modified PA66 fabric (pCA-Fe-SH-PA66) with a static water contact angle (CA) of 154.4° and a sliding angle (SA) of 2°. The resulting pCA-Fe-SH-PA66 demonstrated excellent capabilities in self-cleaning, UV-blocking, photothermal conversion, and oil-water separation. Furthermore, pCA-Fe-SH-PA66 exhibited remarkable antibacterial ability, displaying inhibitory rates of 97.00% against E. coli and 96.15% against S. aureus, respectively. Additionally, it demonstrated noteworthy stability in a series of tests, encompassing 225 min of washing, 1000 cycles of abrasion, 48 h of UV light aging, 48 h of acid/base solution, seawater, and organic reagents immersion. Furthermore, it was demonstrated that three additional plant-derived phenolic compounds, namely 3-hydroxycinnamic acid (HA), polyatin (PD), and 4-hydroxy-3,5-dimethoxycinnamic acid (HDA), can also be effectively utilized for the multifunctional modification of PA66 fabric. The proposed modification method is mild, fast, and simple, offering a novel approach to the multifunctional modification of synthetic materials. The modified PA66 fabric holds potential in applications such as oily wastewater treatment, outdoor sportswear, tents, and other fields.

Facile fabricated transparent anti-smudge coating with high hardness and excellent flexibility from MTQ and branched silicone resins

The demand for high-transparent functional coatings with glass-like hardness, polymer-like flexibility, and anti-smudge properties has increased significantly, especially for foldable touchscreens. However, it is challenging to achieve all the required properties in a coating because the realization of these properties may conflict with each other. In this study, we present a facile method for preparing a special organic-inorganic hybrid coating by utilizing epoxy MTQ silicone resins and amine-terminated hyperbranched polysiloxane (HPSi). The chemical structure of the MTQ resin was fine-tuned to obtain the optimal M/T/Q ratio, and a novel HPSi with rich crosslinking sites and excellent flexibility was prepared as the curing agent. The resulting hybrid network imparted the coating with exceptional hardness (pencil hardness, 7–9H) and excellent flexibility (<2 mm bend diameter). In addition, by modifying the MTQ resin with fluorosilane, the surface energy of the coating was reduced to 14.8 ± 0.4 mJ/m2 and its anti-smudge and self-cleaning properties were improved without sacrificing the transparency of the coating (99.4 % at 550 nm). Notablely, even after 1000 cycles of steel wool abrasion, these coatings still maintain their outstanding performance. This study provides a promising strategy for the development of hard, flexible, and anti-smudge coatings suitable for foldable displays and other related fields.

Design and construction of fluorine-free, cost-effective and robust superhydrophobic coatings using nanosilica with highly covalently bonded octadecyl ligands

Low surface energy and rough structure are two key factors in achieving superhydrophobicity. Currently, one of the common routes to acquire low surface energy is via the hydrolytic modification of organosilanes. However, due to steric hindrance, self-condensation of hydrolyzed silanes predominates, whereby the resulting products are mainly physically adsorbed or attached to the substrate by few bonds, resulting in the formed superhydrophobic surfaces susceptible to damage by external forces, which significantly inhibits their practical application and long-term service. Herein, we prepared a novel functionalized nanosilica with highly chemically grafted octadecyl ligands in a non-aqueous medium. The covalent bond structure of the product (ODS@SiO2) is approved, and an average grafting density of 10 chains nm−2 was calculated. The ODS@SiO2 has a crystal structure and displays superior thermal and chemical resistance. ODS@SiO2 can be homogeneously dispersed in n-hexane and then applied to various substrates pre-coated with an adhesive by directly spraying or dip-coating to create superhydrophobic coatings. Studies demonstrate that the aggregation of the ODS@SiO2 with high grafting octadecyl ligands on a substrate not only provides a stable low-surface energy layer but also creates multi-level hierarchical structures and microspheres, thus strengthening the robustness of the coating. The coatings exhibit excellent water repellency and self-cleaning ability while maintaining superhydrophobicity after multiple cycles of mechanical abrasion and exposure to harsh environmental conditions. We convince that the fluorine-free, cost-effective and robust superhydrophobic coating has potential applications in various fields.

Abrasion‐Resistant and Enhanced Super‐Slippery Flush Toilets Fabricated by a Selective Laser Sintering 3D Printing Technology

Flush toilets waste a significant amount of water every day due to the unavoidable adhesions between human waste and the toilet surfaces. Super‐slippery surfaces can repel complex fluids and various viscoelastic solids, however, are easily broken by mechanical abrasions. Herein, the fabrication of an abrasion‐resistant super‐slippery flush toilet (ARSFT) is reported using a selective laser sintering 3D printing technology. Unlike traditional super‐slippery surfaces with limited thicknesses which can be easily worn away, the powder‐sintered strategy endows the ARSFT not only with a self‐supporting 3D complex shape but also with a porous structure that can accommodate considerable lubricants for an abrasion‐resistant super‐slippery property. As a result, the as‐prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids. Besides liquids, the ARSFT exhibits a high resistance to sticky synthetic feces. Notably, even after being abraded to 1,000 cycles of abrasion using sandpaper, the ARSFT maintains its record‐breaking super‐slippery capability. The concept of the 3D‐printed object with a superior abrasion‐resistant slippery ability will improve the development of super‐slippery materials and further save water consumption in the human society.

LARGE-AREA FABRICATION OF A HARD AND WEAR-RESISTANT SUPERHYDROPHOBIC MATERIAl

Different types of superhydrophobic materials have been fabricated by constructing surfaces with low surface energy and micro-nanostructures, most of which are coatings. Due to the fragile rough structure of the coating, it is very easy to lose its superhydrophobic properties when exposed to friction, corrosion, high temperature, and other effects of the external environment. This has largely hindered the large-scale application of superhydrophobic materials. Here, a rigid superhydrophobic material with polyurethane foam as the substrate, polytetrafluoroethylene (PTFE) nanoparticles as the matrix phase, and carbon nanotubes as the reinforcing phase have been reported. The fabricated material showed excellent superhydrophobicity (157∘ ± 1∘) and robustness. The contact angle of the superhydrophobic material surface remained above 150∘ and the rolling angle below 10∘ after 1000 cycles (distance is 40[Formula: see text]m) of abrasion using 800 # sandpaper at pressure of 5[Formula: see text]kPa.