Continuous and discontinuous transitions between two types of capillary bridges on a beaded chain pulled out from a liquid

Abstract

Capillary bridges can be used for fabricating new materials and structures. Here, we describe theoretically and validate experimentally the mechanism of formation of capillary bridges during a process in which a beaded chain is being pulled out from a liquid with a planar surface. There are two types of capillary bridges present in this system, namely the sphere-planar liquid surface bridge initially formed between the spherical bead leaving the liquid bath and the initially planar liquid surface, and the sphere-sphere capillary bridge formed between neighbouring beads in the part of the chain above the liquid surface. During the process of pulling the chain out of the liquid, the sphere-planar liquid surface bridge transforms into the sphere-sphere bridge. We show that for monodisperse spherical beads comprising the chain, this transition can be either continuous or discontinuous. The transition is continuous when the diameter of the spherical beads is larger than the capillary length. Otherwise, the transition is discontinuous, likewise the capillary force acting on the chain.

Assembly of 1D Granular Structures from Sulfonated Polystyrene Microparticles

“…Such agglomerated structures are typically unstable when the electric field is turned off, whereas chains with a one-particle length are stable in the absence of an electric field. The stability of one-particle long chains is owed to the attractive interaction of the capillary bridges (type II) between two neighboring particles formed from the capillary bridges (type I) just after a particle has passed the liquid-air interface (for details regarding the formation of capillary bridge formation type I and its transition to capillary bridge type II when pulling a chain of spherical particles outside the liquid, we refer to the following research article: [ 1 ]).…”

“…The fabrication of one-dimensional (1D) colloidal and granular materials is presently a very active area of nano- and micromaterials research. Colloidal and granular 1D assemblies offer great opportunities for both fundamental studies [ 1 , 2 , 3 ] and practical applications, including applications in optoelectronics [ 4 ], photonics [ 5 ], sensors [ 6 ], photovoltaics [ 7 ], and flexible electronics [ 8 ]. The 1D assemblies can be composed of either particle groups [ 9 , 10 , 11 ] or individual particles forming particle chain-like structures [ 12 , 13 , 14 ].…”

Migration of Liquid Bridges at the Interface of Spheres and Plates with an Imposed Thermal Gradient

“…For instance, the flow of an oil droplet around a point contact is widely investigated in the context of starved lubrication of ball bearings, and when working under high-temperature/pressure conditions, the migration would exacerbate the starvation in the contact area and cause potential lubrication failure . Viewing from the hydrodynamics, the inner flow at the liquid/gas interface constitutes the migration on free solid surfaces. , When a sphere was encountered, an essential change occurs where the liquid/gas interface transforms to a liquid bridge at the interface, which involves many complex physical problems on the interfacial force balance. − Liquid bridges have been addressed in micro-electromechanical systems, and strategies including applying electric potential gradients, − thermocapillary effects, or special structures can all regulate the locomotion of liquid bridges. However, for the tribological components exposed to thermal gradients, it is unknown how the migration of liquid lubricants progresses at the interface of spheres and plates, and the influence factors of geometric dimensions of solids and physicochemical properties of solids and liquids on the migration performance need to be clarified.…”

“…33,34 When a sphere was encountered, an essential change occurs where the liquid/gas interface transforms to a liquid bridge at the interface, which involves many complex physical problems on the interfacial force balance. 35−39 Liquid bridges have been addressed in micro-electromechanical systems, and strategies including applying electric potential gradients, 40−42 thermocapillary effects, 43 or special structures 44 can all regulate the locomotion of liquid bridges. However, for the tribological components exposed to thermal gradients, it is unknown how the migration of liquid lubricants progresses at the interface of spheres and plates, and the influence factors of geometric dimensions of solids and physicochemical properties of solids and liquids on the migration performance need to be clarified.…”

Capillary forces on a small particle at a liquid-vapor interface: Theory and simulation

“…[21]. Because of its practical importance, the detachment of a particle from a planar liquid surface has been studied for a long time [19,[22][23][24][25][26][27][28][29][30][31][32]. The quasistatic removal of a sphere from a liquid surface has a strong connection with the meniscus on the outside of a cylinder in a liquid bath, which is governed by the Young-Laplace equation.…”