Regulating the dynamic wetting behavior of pesticide on banana leaves at different growth stages with surfactants.

BACKGROUND: Pesticide spraying constitutes an essential component of the production and management regimen within banana orchards, extending throughout the entire growth cycle of the banana plants. Exploring the intricate interplay between surfactants, pesticide formulations, and the evolving surface properties of banana leaves throughout their growth stages is critical to the enhancement of pesticide application methods and the elevation of agricultural productivity. RESULTS: Through investigating the regulatory impact of surfactants on the physicochemical properties of medicinal solutions, this study elucidates the interaction mechanism between the physicochemical properties of pesticides and the surface characteristics of banana leaves. The findings reveal that the energy dissipation rate of pesticide droplets exhibits a natural exponential rise in correlation with the increase in both the We number and the concentration of surfactant present. Comparatively, the adaxial surface of banana leaves demonstrates superior spreading and adhesion properties for droplets than the abaxial surface. Specifically, droplets containing the anionic surfactant sodium dodecyl sulfate on the adaxial surface of banana leaves are found to spread well with a reduced retraction effect. Conversely, the application of the non-ionic surfactant fatty acid polyoxyethylene ether (AEO-3) on the abaxial surface of banana leaves is more beneficial for the wetting and retention of droplets. As banana leaves grow, there is a noted decline in the spreading and retraction properties of droplets. However, droplets have a higher propensity to wet and adhere to the surfaces of mature banana leaves. CONCLUSION: To bolster the adherence of pesticide droplets to leaf surfaces, it is imperative to ensure they possess superior spreading properties and a controlled retraction pace. This facilitates an extended period of contact and enhanced stability, thereby optimizing the spray's deposition efficacy. © 2024 Society of Chemical Industry.

Wetting Behavior-Induced Interfacial transmission of Energy and Signal: Materials, Mechanisms, and Applications.

Wetting behaviors can significantly affect the transport of energy and signal (E&S) through vapor, solid, and liquid interfaces, which has prompted increased interest in interfacial science and technology. E&S transmission can be achieved using electricity, light, and heat, which often accompany and interact with each other. Over the past decade, their distinctive transport phenomena during wetting processes have made significant contributions to various domains. However, few studies have analyzed the intricate relationship between wetting behavior and E&S transport. This review summarizes and discusses the mechanisms of electrical, light, and heat transmission at wetting interfaces to elucidate their respective scientific issues, technical characteristics, challenges, commonalities, and potential for technological convergence. The materials, structures, and devices involved in E&S transportation are also analyzed. Particularly, harnessing synergistic advantages in practical applications and constructing advanced, multifunctional, and highly efficient smart systems based on wetted interfaces is the aim to provide strategies.

Defect by design: Harnessing the "petal effect" for advanced hydrophobic surface applications.

HYPOTHESIS: In the interfacial wetting boundary, the superhydrophobic surface is often damaged, and the anisotropic wettability of its surface has attracted many researchers' attention. The "petal effect" surface has typical anisotropic wettability. We predict that under the dual conditions of structural defects and high impact velocity, the "petal effect" becomes more adhesive on the surface. EXPERIMENTS: This study refers to the droplet state on rose petals, structural defects were constructed on the superhydrophobic surface. This paper studies the influence of macro-structural defects on the wettability change from natural to bionic "lotus effect" to "petal effect" in both static and dynamic angles. FINDINGS: Macro defects significantly change the static contact angle of the superhydrophobic surface. The higher the impact velocity of the droplet, the higher the energy dissipation of the "petal effect" surface (DSHS), which improves the adhesion of the surface to the droplet and prolongs the contact time. It is found that the defect structure and high impact velocity will directly affect the deposition and desorption of droplets on the superhydrophobic surface, and they are both essential. This wetting dynamic law is very likely to be helpful in the quantitative design of defect structure scale for dynamic desorption of droplets on superhydrophobic surfaces.

Molecular dynamics study of the corrosion protection improvement of superhydrophobic dodecyltrimethoxysilane film on mild steel.

Recently, superhydrophobic surfaces have received increasing interest in metal corrosion protection due to their excellent waterproofing characteristics. However, little attention has been paid to the related anti-corrosion mechanism at the molecular level. In this work, the protection behaviors provided by the superhydrophobic dodecyltrimethoxysilane for mild steel were first explored using molecular dynamics (MD) simulation in terms of silane absorption orientations and water cluster wetting behaviors. The results show that the conformations of dodecyltrihydroxysilane (DTHS) on the Fe substrate are greatly dependent on the solvent environment. Typically, the DTHS molecule adopts a "standing" orientation with the hydrophilic head attached to the Fe surface and the hydrophobic tail remaining in the polar phase, which is conducting to generate a good repulsive effect on the water droplet. Based on this, the diffusion performance of corrosive species in the superhydrophobic DTHS film was further investigated. The computational results indicate that the corrosive species are confined to specific regions of the film, which results in a decreased diffusion coefficient. Additionally, the weak movement of DTHS molecules also increases the transport resistance of the corrosive medium through the superhydrophobic DTHS film, thereby improving the corrosion protection of the underlying metal substrate. The results obtained in this work will deepen our understanding of the anticorrosion mechanism of superhydrophobic silane films.

Wetting of Cell Aggregates on Microdisk Topography Structures Achieved by Maskless Optical Projection Lithography.

Cell aggregates as a 3D culture model can effectively mimic the physiological processes such as embryonic development, immune response, and tissue renewal in vivo. Researches show that the topography of biomaterials plays an important role in regulating cell proliferation, adhesion, and differentiation. It is of great significance to understand how cell aggregates respond to surface topography. Herein, microdisk array structures with the optimized size are used to investigate the wetting of cell aggregates. Cell aggregates exhibit complete wetting with distinct wetting velocities on the microdisk array structures of different diameters. The wetting velocity of cell aggregates reaches a maximum of 293 µm h-1 on microdisk structures with a diameter of 2 µm and is a minimum of 247 µm h-1 on microdisk structures of 20 µm diameter, which suggests that the cell-substrates adhesion energy on the latter is smaller. Actin stress fibers, focal adhesions (FAs), and cell morphology are analyzed to reveal the mechanisms of variation of wetting velocity. Furthermore, it is demonstrated that cell aggregates adopt climb and detour wetting modes on small and large-sized microdisk structures, respectively. This work reveals the response of cell aggregates to micro-scale topography, providing guidance for better understanding of tissue infiltration.

Interface Wetting Driven by Laplace Pressure on Multiscale Topographies and Its Application to Performance Enhancement of Metal-Composite Hybrid Structure.

Surface topography reconstruction is extensively used to address the issue of weak bonding at the polymer-metal interface of metal-composite hybrid structure, while enhancement from this approach is seriously impaired by insufficient interface wetting. In this study, the wetting behavior of polymer on aluminum surfaces with multiscale topographies was theoretically and experimentally investigated to realize stable and complete wetting. Geometric dimensions of multiscale surface topographies have a notable impact on interfacial forces at the three-phase contact line of polymer/air/aluminum, and a competition exists between Laplace pressure and bubble pressure in dominating the wetting behavior. Laplace pressure facilitates the degassing of trapped air bubbles in grooves, bringing more robust interfacial wettability to grooves than dimples and grids. Conversely, dimples with excessive dimensions generate interfacial pores, and this intrinsic mechanism is theoretically unraveled. Moreover, different degrees of interface wetting cause variations in bonding strength of polymer-aluminum interface, which changes from ∼18% improvement to ∼17% reduction compared to original strength. Finally, groove topography perfectly achieved complete wetting between polymer and aluminum and consequently improved flexure performance by over 11% for the aluminum-carbon fiber hybrid side impact bar, which verifies the importance of complete wetting at a part scale. This study deepens the understanding of wetting behavior and clarifies the intrinsic correlation between interfacial bonding performance and surface topography.

Regulating droplet impact and wetting behaviors on hydrophobic leaves using a nonionic surfactant.

Droplet rebound from hydrophobic leaves is a major factor influencing pesticide utilization. The use of a surfactant is a major strategy to reduce droplet rebound, promoting pesticide deposition on hydrophobic agricultural plant leaves. However, most surfactants known to regulate droplet rebound are either anionic or cationic. In this study, ethoxylated propoxylated 2-ethyl-1-haxanol (EH 6) was identified as a nonionic surfactant that inhibits droplet rebound while promoting the complete spreading of the droplet on hydrophobic leaves. Compared with the widely reported nonionic surfactant Tween 20, EH 6 performs better at concentrations above 0.3%. This phenomenon can be attributed to the rapid migration of EH 6 from the bulk to the newly generated interface, significantly reducing the surface tension. We introduce a simple and effective strategy that can be used to enhance droplet deposition on hydrophobic plant surfaces, which may offer future economic and environmental benefits.

Kinetic analysis of wetting and spreading at high temperatures: A review.

The kinetic factors of the liquid-solid interface formation process are extremely useful in the design of composite preparation methods and the manufacture of comprehensive performance-controlled metal- or ceramic-based composites. Here, we review the available spreading dynamic models, focusing on wetting at high temperatures. There is yet to be developed a general spreading dynamic model with complete physical meaning that can accurately describe complicated surface-interface kinetic processes at high temperatures. In this work, we highlight common analysis errors in the description of the spreading dynamics for metal-ceramic and metal-metal systems. By unifying the expressions of the spreading dynamic models as the function f(v, θd) and fitting the experimental data reported in the literature, we discovered that the molecular-kinetic model commonly used to describe adsorption-controlled spreading at room temperature and reaction-limited spreading model used at high temperature have a certain range of overlap. When the condition σlv(cosθe-cosθd) < <2nkBT is satisfied, these models are consistent in terms of mathematical functional expressions. As a result, distinguishing between them when the spreading behavior includes both adsorption and reaction is challenging.

Banana Leaf Surface's Janus Wettability Transition from the Wenzel State to Cassie-Baxter State and the Underlying Mechanism.

Janus wettability plays an important role in certain special occasions. In this study, field emission scanning electron microscopy (FESEM) was used to observe the surface microstructure of banana leaves, the static wettability of the banana leaf surface was tested, and the dynamic response of water droplets falling at different heights and hitting on the adaxial and abaxial sides was studied. The study found that the nanopillars on the adaxial and abaxial sides of the banana leaf were different in shape. The nanopillars on the adaxial side were cone-shaped with large gaps, showing hydrophilicity (Wenzel state), and the heads of the nanopillars on the abaxial side were smooth and spherical with small gaps, showing weak hydrophobicity (Cassie-Baxter state). Banana leaves show Janus wettability, and the banana leaf surface has high adhesion properties. During the dynamic impact test, the adaxial and abaxial sides of the banana leaves showed different dynamic responses, and the wettability of the adaxial side of the banana leaves was always stronger than the abaxial side. Based on the structural parameters of nanopillars on the surface of the banana leaf and the classical wetting theory model, an ideal geometric model around a single nanopillar on both sides of the banana leaf was established. The results show that the established model has high accuracy and can reflect the experimental results effectively. When the apparent contact angle was 76.17°, and the intrinsic contact angle was 81.17° on the adaxial side of the banana leaf, steady hydrophilicity was shown. The abaxial side was similar. The underlying mechanism of Janus wettability on the banana leaf surface was elucidated. This study provides an important reference for the preparation of Janus wettability bionic surfaces and the efficient and high-quality management of banana orchards.

Regulating Droplet Wetting and Pinning Behaviors on Pathogen-Modified Hydrophobic Surfaces: Strategies and Working Mechanisms.

Hydrophobic surfaces modified by pathogens in agricultural production are one of the main reasons to reduce the utilization of pesticides. Adding surfactants to pesticide solutions is a common method to improve their wetting and spreading properties. In this work, the interaction mechanism between pathogen-modified hydrophobic surfaces and mixtures of surfactants and a pesticide was studied in detail. The interaction mechanism was determined by characterizing the wetting and spreading behaviors of droplets on cucumber powdery mildew leaves at different growth stages. When surfactants were added, droplets on cucumber powdery mildew leaves were in the Wenzel wetting state, the pinning force weakened, the contact line speed accelerated, and the adhesion force increased. We explained the micellar state and aggregation behavior of surfactant molecules in a pesticide solution that was applied to the surface of cucumber powdery mildew leaves. Droplets of solutions containing nonionic surfactants easily formed semibald micelles, binding to the pathogen of powdery mildew, whereas droplets containing cationic surfactants did not do so. Because of the electrostatic interaction between cationic surfactant molecules and powdery mildew pathogens, cationic surfactant molecules did not wet the pathogens very well, so we suggest adding nonionic surfactants rather than cationic surfactants to improve the wetting and spreading of pesticide solutions on cucumber powdery mildew leaves. This study provides new insights into enhancing the wetting and deposition of droplets on pathogen-modified hydrophobic surfaces.

Topography quantifications allow for identifying the contribution of parental strains to physical properties of co-cultured biofilms.

Most biofilm research has so far focused on investigating biofilms generated by single bacterial strains. However, such single-species biofilms are rare in nature where bacteria typically coexist with other microorganisms. Although, from a biological view, the possible interactions occurring between different bacteria are well studied, little is known about what determines the material properties of a multi-species biofilm. Here, we ask how the co-cultivation of two B. subtilis strains affects certain important biofilm properties such as surface topography and wetting behavior. We find that, even though each daughter colony typically resembles one of the parent colonies in terms of morphology and wetting, it nevertheless exhibits a significantly different surface topography. Yet, this difference is only detectable via a quantitative metrological analysis of the biofilm surface. Furthermore, we show that this difference is due to the presence of bacteria belonging to the 'other' parent strain, which does not dominate the biofilm features. The findings presented here may pinpoint new strategies for how biofilms with hybrid properties could be generated from two different bacterial strains. In such engineered biofilms, it might be possible to combine desired properties from two strains by co-cultivation.

Efficient pesticide formulation and regulation mechanism for improving the deposition of droplets on the leaves of rice (Oryza sativa L.).

BACKGROUND: The effective deposition of pesticide droplets on the target leaf surface is critical for improving the utilization of pesticides. We proposed a new way to enhance the droplet deposition on the target leaf surface by changing the properties of pesticide formulation, and this formulation can be sprayed directly or at a low dilution. In addition, it is a simple method to select a suitable concentration and formulation by evaluating the interfacial dilational rheological properties of pesticide droplets. RESULTS: The wetting behavior of two types of pesticide formulations prepared by oil-based solvent on the rice leaf surface was investigated based on the surface free energy, surface tension, contact angle, adhesion tension, and adhesion work. The interfacial dilational rheological properties of different pesticide solutions were measured as a function of concentration. This study clearly demonstrates the fact that water-in-oil emulsion has a better wettability than oil-in-water emulsion, especially with the increase of the concentration of the solution, the droplets can be wetted and spread faster on the leaves. Compared with vegetable oil (methyl oleate), mineral oil (solvent oil No. 200) has smaller dilational modulus and surface tension, showing excellent wetting properties. CONCLUSION: The water-in-oil emulsion prepared with solvent oil No. 200 has the smallest dilational modulus, and the spray droplets spread rapidly to the maximum wetting area on the rice leaves, which can be used in an ultra-low volume spray. The results provide new insights into how to increase the deposition of droplets on superhydrophobic leaf surfaces by screening formulations and concentrations. © 2021 Society of Chemical Industry.

Wetting Behavior of LBE on Corroded Candidate LFR Structural Materials of 316L, T91 and CLAM.

In this work, the wetting behaviors of lead-bismuth eutectic (LBE) on corroded 316L, T91, and CLAM surfaces were studied. The wettability of LBE on virgin and corroded surfaces were tested at 450 °C by using the sessile-drop (SD) method after immersing the samples in LBE with saturated oxygen concentration for 400, 800, and 1200 h at 450 °C. Additionally, the morphology, as well as element distribution of the corrosion structure, were characterized by scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). The results showed that the virgin samples of three materials are non-wetting to LBE, and the formation of corrosion structures further reduces the wettability. Besides, the thickness of the corrosion layer formed on the 316L surface grew more slowly than the other two steel, which results in better corrosion resistance of austenitic steel 316L than that of ferritic/martensitic steels T91 and CLAM at 450 °C. Meanwhile, the morphology and distribution of corrosion products are important factors affecting the wettability of the steel surface. The formation of corrosion products with high roughness as well as disorder results in a significant reduction in surface wettability.

Time-Dependent Wetting Scenarios of a Water Droplet on Surface-Energy-Controlled Microcavity Structures with Functional Nanocoatings.

We report the surface-energy-dependent wetting transition characteristics of an evaporating water droplet on surface-energy-controlled microcavity structures with functional nanocoatings. The droplet wetting scenarios were categorized into four types depending on the synergistic effect of surface energy and pattern size. The silicon (Si) microcavity surfaces (γSi = 69.8 mJ/m2) and the polytetrafluoroethylene (PTFE)-coated microcavity surfaces (γPTFE = 15.0 mJ/m2) displayed stable Wenzel and Cassie wetting states, respectively, irrespective of time. In contrast, diamond-like carbon (DLC)-coated (γDLC = 55.5 mJ/m2) and fluorinated diamond-like carbon (FDLC)-coated (γFDLC = 36.2 mJ/m2) surfaces demonstrated a time-dependent transition of wetting states. In particular, the DLC-coated surface showed random filling of microcavities at the earlier time point, while the FDLC-coated surface displayed directional filling of microcavities at the late stage of drop evaporation. Such dynamic wetting scenarios based on surface energy, in particular, the random and directional wetting transitions related to surface energy of nanocoatings have not been explored previously. Furthermore, the microscopic role of nanocoating in the wetting scenarios was analyzed by monitoring the time-dependent deformation and movement of the air-water interface (AWI) at individual cavities using the fluorescence interference-contrast (FLIC) technique. A coating-dependent depinning mechanism of the AWI was responsible for variable filling of cavities leading to time-dependent wetting scenarios. A capillary wetting model was used to relate this depinning event to the evaporation-induced internal flow within the droplet. Interestingly, FLIC analysis revealed that a hydrophilic nanocoating can induce microscopic hydrophobicity near the cavity edges leading to delayed and variable cavity filling. The surface energy-dependent classification of the wetting scenarios may help the design of novel evaporation-assisted thermodynamic and mass-transfer processes.

Atomistic Investigation on the Wetting Behavior and Interfacial Joining of Polymer-Metal Interface.

Polymer-metal hybrid structures can reduce the weight of components while ensuring the structural strength, which in turn save cost and subsequently fuel consumption. The interface strength of polymer-metal hybrid structure is mainly determined by the synergistic effects of interfacial interaction and mechanical interlocking. In this study, the wetting behavior of polypropylene (PP) melt on metal surface was studied by molecular dynamics simulation. Atomistic models with smooth surface and nano-column arrays on Al substrate were constructed. Influences of melt temperature, surface roughness and metal material on the wetting behavior and interfacial joining were analyzed. Afterwards the separation process of injection-molded PP-metal hybrid structure was simulated to analyze joining strength. Results show that the initially sphere-like PP model gradually collapses in the wetting simulation. With a higher temperature, it is easier for molecule chains to spread along the surface. For substrate with rough surface, high density is observed at the bottom or on the upper surface of the column. The contact state is transitioning from Wenzel state to Cassie-Baxter state with the decrease of void fraction. The inner force of injection-molded PP-Fe hybrid structure during the separation process is obviously higher, demonstrating a greater joining strength.

Characterization of wetting using topological principles.

HYPOTHESIS: Understanding wetting behavior is of great importance for natural systems and technological applications. The traditional concept of contact angle, a purely geometrical measure related to curvature, is often used for characterizing the wetting state of a system. It can be determined from Young's equation by applying equilibrium thermodynamics. However, whether contact angle is a representative measure of wetting for systems with significant complexity is unclear. Herein, we hypothesize that topological principles based on the Gauss-Bonnet theorem could yield a robust measure to characterize wetting. THEORY AND EXPERIMENTS: We introduce a macroscopic contact angle based on the deficit curvature of the fluid interfaces that are imposed by contacts with other immiscible phases. We perform sessile droplet simulations followed by multiphase experiments for porous sintered glass and Bentheimer sandstone to assess the sensitivity and robustness of the topological approach and compare the results to other traditional approaches. FINDINGS: We show that the presented topological principle is consistent with thermodynamics under the simplest conditions through a variational analysis. Furthermore, we elucidate that at sufficiently high image resolution the proposed topological approach and local contact angle measurements are comparable. While at lower resolutions, the proposed approach provides more accurate results being robust to resolution-based effects. Overall, the presented concepts open new pathways to characterize the wetting state of complex systems and theoretical developments to study multiphase systems.

Assessment of milkweed floss as a natural hollow oleophilic fibrous sorbent for oil spill cleanup.

Natural oil sorbent materials with a high oil sorption capacity have recently received remarkable attention for oil spill cleanup from seawater. This study reports on the development of a superhydrophobic hollow cellulosic fiber that could serve as an oil spill cleanup material. As oil sorption is based on the physical and chemical characteristics of the sorbent, FTIR, SEM, XRD, and surface contact angle of the fibers were determined. A series of tests were then carried out to analyze the sorption capacity, dynamic oil retention, and reusability. Subsequently, the effect of the fibers' weight on the amount of oil absorption and absorption time was investigated. The wettability analyses showed that the milkweed floss fiber possessed a superhydrophobic characteristic (with the water contact angle of 140°). The empty channel of the fiber was more than 90% of its total volume. The hydrophobicity and capillary properties helped the fibers to absorb up to 100 g/g of oil, which was higher than that obtained by many natural cellulosic fibers.

The wetting behavior of three different types of aqueous surfactant solutions on housefly (Musca domestica) surfaces.

BACKGROUND: It is difficult for insecticide spray droplets to adhere to highly hydrophobic pest surfaces, and this is an important reason behind the low utilization of pesticides. Greater understanding of the wetting behaviors of agro-surfactants on pest surfaces is of great importance in pesticidal applications. RESULTS: This research investigated the wetting processes of three surfactant solutions [TritonX-100 (TX-100), sodium dodecyl sulfate (SDS) and dodecyl trimethyl ammonium bromide (DTAB)] on housefly surfaces based on surface tension, contact angles and solid-liquid interaction. As the surfactant concentration increased, the wetting abilities of the solutions improved due a decrease in liquid surface tension. The decrease in contact angles followed an inverted 'S' shape until the concentration exceeded the critical micelle concentration, at which point surfactant adsorption was saturated at the interfaces. The nonionic surfactant TX-100 enhanced wettability more than the ionic surfactants SDS and DTAB. The wetting states of the three surfactant solutions on housefly surfaces transformed to the Wenzel state when the surfactant molecules adsorbed at solid-liquid interfaces (ΓSL ) were 3.09-5.36 times higher than those adsorbed at liquid-air interfaces (ΓLV ). More insecticides attached to housefly surfaces and pesticide utilization was significantly improved after adding TX-100 to the pesticide solution. CONCLUSION: Surfactant TX-100 could be a practical and efficient candidate adjuvant for insecticide spraying of houseflies. This research investigated the wetting mechanism of three different types of surfactant solutions on housefly surfaces, and could provide effective guidance for the preparation of insecticide formulations and pesticide adjuvants with better wettability to improve pesticide utilization. © 2019 Society of Chemical Industry.

Imparting Superhydrophobicity with a Hierarchical Block Copolymer Coating.

A robust and transparent silica-like coating that imparts superhydrophobicity to a surface through its hierarchical multilevel self-assembled structure is demonstrated. This approach involves iterative steps of spin-coating, annealing, and etching of polystyrene-block-polydimethylsiloxane block copolymer thin films to form a tailored multilayer nanoscale topographic pattern with a water contact angle up to 155°. A model based on the hierarchical topography is developed to calculate the wetting angle and optimize the superhydrophobicity, in agreement with the experimental trends, and explaining superhydrophobicity arising through the combination of roughness at different lengthscales. Additionally, the mechanical robustness and optically passive properties of the resulting hydrophobic surfaces are demonstrated.

Femtosecond Laser Fabricated Elastomeric Superhydrophobic Surface with Stretching-Enhanced Water Repellency.

Highly stretchable and robust superhydrophobic surfaces have attracted tremendous interest due to their broad application prospects. In this work, silicone elastomers were chosen to fabricate superhydrophobic surfaces with femtosecond laser texturing method, and high stretchability and tunable adhesion of the superhydrophobic surfaces were demonstrated successfully. To our best knowledge, it is the first time flexible superhydrophobic surfaces with a bearable strain up to 400% are fabricated by simple laser ablation. The test also shows that the strain brings no decline of water repellency but an enhancement to the superhydrophobic surfaces. In addition, a stretching-induced transition from "petal" state to "lotus" state of the laser-textured surface was also demonstrated by non-loss transportation of liquid droplets. Our results manifest that femtosecond laser ablating silicone elastomer could be a promising way for fabricating superhydrophobic surface with distinct merits of high stretchability, tunable adhesion, robustness, and non-fluorination, which is potentially useful for microfluidics, biomedicine, and liquid repellent skin.