To characterize porous media, use is often made of the Lucas−Washburn equation, which relates rate capillary penetration a given liquid to an effective cylindrical pore radius and contact angle between medium. Here, we extend previous large-scale molecular dynamics simulations developed for flat substrates show how this tool can be used study imbibition in some detail. In particular, demonstrate that depends on wetting, especially during early stages filling, leads reduction penetration. The...

Studies on carbon fiber (CF)/poly(ether ether ketone) (PEEK) hybrid textiles were initiated several decades ago because their flexibility and conformability make them a promising alternative to traditional prepregs. The adhesion between the CFs PEEK is mostly controlled by inherent surface properties mutual wettability. However, details of these remain largely unknown, especially those PEEK. Therefore, determine interfacial fibers, we performed comprehensive study characterized topography...

In this work, we study interactions of five different hemicellulose models, i.e. Galactoglucomannan, O-Acetyl-Galactoglucomannan, Fuco-Galacto-Xyloglucan, 4-O-Methylglucuronoxylan, and 4-O-Methylglucuronoarabinoxylan, their respective binding strength to cellulose nanocrystals by molecular dynamics simulations. Glucuronoarabinoxylan showed the highest free energy binding, whereas Xyloglucan had lowest interaction energies amongst models. We further performed simulated shear tests concluded...

We present new spreading-drop data obtained over four orders of time and apply our analysis tool G-Dyna to demonstrate the specific range which various models dynamic wetting would seem for experimental system. follow contact angle radius dynamics liquids on smooth silica surface silicon wafers or PET from first milliseconds several seconds. Analysis images allows us make hundred droplet measurements with great accuracy. The software is then used fit relevant theory (hydrodynamic,...

In 1805, Thomas Young was the first to propose an equation predict value of equilibrium contact angle a liquid on solid. Today, force exerted by solid, such as flat plate or fiber, is routinely used assess this angle. Moreover, it has recently become possible study wetting at nanoscale using atomic microscope. Here, we report use molecular-dynamics simulations investigate distribution along 15 nm fiber dipped into meniscus. We find very good agreement between measured and that predicted...

Wettability as determined from contact angle measurements is a suitable parameter for characterizing the physical bonding of polymer matrix and reinforcing fibers, but it very challenging to measure capillary force exerted by probe liquid on fiber accurately fine fibers such single carbon fibers. Herein, we propose an innovative method measuring dynamic angles with tensiometer, considering both intrinsic variability diameter extremely small amplitude forces, allowing measurement reliable...

We report an experimental study of the dynamics spontaneous spreading aqueous glycerol drops on glass. For a range concentrations, we follow evolution radius and contact angle over several decades time investigate influence solution viscosity. The application molecular kinetic theory to resulting data allows us extract coefficient contact-line friction ζ, jump frequency κ(0), length λ for each solution. Our results show that modified theory, which explicitly accounts effect viscosity, can...

Fibers made from CNTs (CNT fibers) have the potential to form high-strength, lightweight materials with superior electrical conductivity. CNT fibers attracted great attention in relation various applications, particular as conductive electrodes energy such capacitors, lithium-ion batteries, and solar cells. Among these, wire-shaped supercapacitors demonstrate advantages for use wearable electronics. However, making uniform structures desirable electrochemical performances still remains a...

Despite the key to adhesion between polymers and a plethora of materials, our understanding reactive wetting is still rudimentary. In present work, we report dynamics molten maleic anhydride-grafted polypropylene (MA-g-PP) liquids modeled by molecular-kinetic theory (MKT). The dependencies contact line friction (ζ) viscosity (η) were compared for nonreactive polymer systems. Compared with linear ζ η systems, system presented nonlinear relationship. capillary regime, chemistry-affected regime...

Forced wetting experiments with various liquids were conducted to study the dynamic properties of nylon filament. The molecular-kinetic theory (MKT) was used interpret contact angle data and evaluate contact-line friction ζ0 at microscopic scale. By taking account viscosity liquid, could be related exponentially reversible work adhesion. This clearly establishes an experimental link between static material. Moreover, statistical analysis equilibrium molecular displacement frequency K0 length...

Wetting dynamics drive numerous processes involving liquids in contact with solid substrates a wide range of geometries. The spreading organic and liquid metals at, respectively, room temperature >1000 °C have been studied extensively, both experimentally numerically; however, almost no attention has paid to the wetting behavior molten drops thermoplastic polymers, despite its importance, for example, processing fiber-reinforced polymer composites. Indeed, ability classical theories dynamic...

Cellulose nanocrystals (CNCs) offer excellent mechanical properties. However, measuring the strength by performing reliable experiments at nanoscale is challenging. In this paper, we model Iβ crystalline cellulose using reactive molecular dynamics simulations. Taking fibril twist into account, structural changes and hydrogen-bonding characteristics of CNCs during tensile test are inspected failure mechanism analyzed down to scale individual bonds. The C4-O4 glycosidic bond found be...

Droplet impacting and freezing on solid surfaces are ubiquitous in nature crucial to many industrial applications, while the underlying mechanism of this phenomenon remains elusive. In paper, effect surface wettability dynamic behaviors a water droplet substrate at fixed Weber number 200 has been experimentally investigated various temperatures from −35.2 −10 °C. With decrease temperature superhydrophobic surface, complete rebound behavior moves partial ultimately full adhesion, mainly due...

Superhydrophobic surfaces were prepared from solutions of isotactic polypropylenes various molecular weights using soft chemistry. Varying the conditions experiments (polymer concentration and initial amount coated solution) allowed us to optimize superhydrophobic behavior polymer film. Results show that decreasing and/or film thicknesses decreases probability get superhydrophobicity for all tested. Measurement analysis advancing receding contact angles as well estimation surface homogeneity...

We propose a new theoretical model of dynamic wetting for systems comprising two immiscible liquids, in which one liquid displaces another from the surface solid. Such are important many industrial processes and natural world. The is an extension molecular-kinetic theory offers way to predict dynamics two-liquid system individual its parent liquids. also present results large-scale molecular simulations one- show them be good agreement with model. Finally, we that consistent limited data...