Industrial Chemistry & Materials最新文献

Microbubbles have attracted considerable attention due to their distinctive properties, such as large surface area, inherent self-compression, and exceptional mass transfer efficiency. These features render microbubbles valuable across a diverse range of industries, such as water treatment, mineral flotation, and the food industry. While several methods for microbubble generation exist, the gas–liquid membrane dispersion technique emerges as a reproducible and efficient alternative. Nevertheless, conventional approaches struggle to achieve active in situ control of bubble generation. In this study, we introduce an electrostatically responsive liquid gating system (ERLGS) designed for the active management of microbubble production. Utilizing electric fields and anionic surfactants, our system showcases the capability to dynamically regulate bubble size by manipulating the solid–liquid adsorption. Experiments confirm that this active control relies on the electrostatic adsorption and desorption of anionic surfactants, thereby regulating the interactions among the solid–liquid–gas interfaces. Our research elucidates the ERLGS's ability of precisely controlling the generation of bubbles in situ, enabling nearly one-order-of-magnitude change in bubble size, underscoring its applicability in various fields.

Keywords: Liquid gating system; Electrostatic response; Anionic surfactants; Adsorption and desorption; Microbubbles.

Developing a stable, reliable, and industrially compatible method to control hydrophobicity is crucial for separation, transportation, and the generation of special surfaces. An e-HMS-PDMS silica gel nanoparticle coating was prepared using a two-step electron beam irradiation (EBI) process, consisting of (i) grafting of two organic groups onto thiol-functionalized hollow mesoporous silica (HMS-SH) with 10 MeV EBI and (ii) curing of polydimethylsiloxane (PDMS) onto silicone rubber using the HMS hybrid materials prepared in step i as an additive with 200 keV EBI. The tuneable grafting of functional groups and the surface properties of the silica, which was embedded in the PDMS layer, allowed us to precisely control the hydrophilicity of the PDMS layer by means of altering the grafting gradient of the silica and the loading ratio of the monomers. A diverse range of vinyl-structured monomers can be used in this method, and the selection of suitable monomers is vital in determining the physical properties of the coating layer. The hydrophilicity of the coating can be linearly controlled within a specific range (50° to 155°) by using suitable monomers, allowing for the design of surfaces with specific hydrophilic and hydrophobic requirements.

Keywords: Electron beam irradiation; Nanoparticle composite coating; Hydrophilicity/hydrophobicity; Thiol-ene click reaction.

With the trend towards miniaturization in soft robotics, most microactuators encounter challenges in achieving versatile deformations. Here, we present an innovative microactuator design featuring reciprocal deformation, activated solely by humidity changes. These microactuators adopt an asymmetric microfiber configuration, characterized by a core–shell structure with a hydrophilic shell encapsulating hydrophobic microparticles. Utilizing droplet microfluidics for fabrication enables precise control over microfiber morphology and internal microparticles. During hygroscopic actuation, these microactuators undergo a unique two-stage deformation, exhibiting opposite trends in curvature variation—a stark departure from the unidirectional deformations observed in previous microactuators. The anisotropy inherent in asymmetric microfibers governs water absorption and desorption, driving this distinctive reciprocal deformation. These microactuators demonstrate versatility in controlled droplet transport and solid cargo manipulation, expanding their potential applications. This study not only unveils novel mechanisms but also broadens the functional spectrum of microactuators.

Keywords: Microactuators; Reciprocal deformation; Droplet microfluidics; Asymmetric microfiber; Liquid templates.