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期刊论文 4

年份

2021 2

关键词

主-客体化学 1

微胶囊 1

液-液界面 1

自组装 1

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Preparation, with graphene, of novel biomimetic self-healing microcapsules with high thermal stability

《结构与土木工程前沿（英文）》页码 1188-1198 doi: 10.1007/s11709-023-0027-5

摘要： This paper reports a comparative study of microcapsules with enhanced thermal stability and electrical conductivity inspired by the bionic thermal insulation of birds’ feathers for self-healing aged asphalt. The work is based on an in situ polymerization with composite shell components of graphene and hexamethoxymethylmelamine resin. By using graphene, microcapsules with rough surfaces are achieved, improving the interface between microcapsules and asphalt. In addition, the microcapsules’ initial thermal decomposition temperature is appropriately high, so that the stability of the microcapsule in the asphalt highway system is protected. The proportion of graphene in the microcapsule shell can regulate the microcapsule’s heat resistance because graphene modifies the shell’s structural makeup. Additionally, the microcapsules’ electrical conductivity is relatively high. The self-healing capability of bitumen sharply increases, providing benefit to the effect of microcapsules on the properties of aged asphalt.

关键词： graphene microcapsule bitumen heat insulation conductivity

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Porous ultrathin-shell microcapsules designed by microfluidics for selective permeation and stimuli-triggered

《化学科学与工程前沿（英文）》页码 1643-1650 doi: 10.1007/s11705-022-2201-z

摘要： Microcapsules are versatile delivery vehicles and widely used in various areas. Generally, microcapsules with solid shells lack selective permeation and only exhibit a simple release mode. Here, we use ultrathin-shell water-in-oil-in-water double emulsions as templates and design porous ultrathin-shell microcapsules for selective permeation and multiple stimuli-triggered release. After preparation of double emulsions by microfluidic devices, negatively charged shellac nanoparticles dispersed in the inner water core electrostatically complex with positively charged telechelic α,ω-diamino functionalized polydimethylsiloxane polymers dissolved in the middle oil shell at the water/oil interface, thus forming a porous shell of shellac nanoparticles cross-linked by telechelic polymers. Subsequently, the double emulsions become porous microcapsules upon evaporation of the middle oil phase. The porous ultrathin-shell microcapsules exhibit excellent properties, including tunable size, selective permeation and stimuli-triggered release. Small molecules or particles can diffuse across the shell, while large molecules or particles are encapsulated in the core, and release of the encapsulated cargos can be triggered by osmotic shock or a pH change. Due to their unique performance, porous ultrathin-shell microcapsules present promising platforms for various applications, such as drug delivery.

关键词： microcapsule emulsion microfluidics selective permeation stimuli-triggered release

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Development of barium@alginate adsorbents for sulfate removal in lithium refining

Lisa Xu, Kaifei Chen, George Q. Chen, Sandra E. Kentish, Gang (Kevin) Li

《化学科学与工程前沿（英文）》 2021年第15卷第1期页码 198-207 doi: 10.1007/s11705-020-1968-z

摘要： The demand for lithium has been steadily growing in recent years due to the boom of electric cars. High purity lithium is commonly used in the manufacture of battery grade lithium electrolyte. Sulfate residuals originating from acid leaching of lithium ores must be limited to below 20 mg·L during refining. There are methods to remove sulfate such as membrane processing and chemical precipitation using barium salts. However, membrane separation is unable to achieve the required purity while chemical precipitation often causes secondary contamination with barium and requires extra filtration processes that lead to increased processing costs. In this study, we developed a polymeric matrix entrapped with barium ions as a novel adsorbent to selectively adsorb sulfate in aqueous solutions. The adsorbent was prepared by dropwise injection method where alginate droplets were crosslinked with barium to form hydrogel microcapsules. In a typical scenario, the microcapsules had a diameter of 3 mm and contained 5 wt-% alginate. The microcapsules could successfully reduce sulfate concentration in a solution from 100 to 16 mg·L , exceeding the removal target. However, the microcapsules were mechanically unstable in the presence of an excess amount of sulfate. Hence, calcium ions were added as a secondary crosslinking agent to improve the integrity of the microcapsules. The two-step Ca/Ba@alginate microcapsules showed an exceptional adsorption performance, reducing the sulfate concentration to as low as 0.02 mg·L . Since the sulfate selective microcapsules can be easily removed from the aqueous system and do not result in secondary barium contamination, these Ca/Ba@alginate adsorbents will find applications in ultra-refining of lithium in industry.

关键词： barium@alginate microcapsules dropwise injection sulfate removal lithium

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基于液-液界面的主-客体分子识别 Review

王贝贝, 陈浩, 刘倓, 史少伟, Thomas P. Russell

《工程（英文）》 2021年第7卷第5期页码 603-614 doi: 10.1016/j.eng.2021.02.004

摘要：

由于动态和可逆的性质，主-客体识别作为一种非共价键相互作用，赋予了液-液界面独特的性质，包括刺激响应性和自调节性等。近年来，越来越多的研究致力于通过在液-液界面上集成功能性单元（如胶体粒子、聚合物）来构筑二维薄膜和微胶囊等超分子界面体系，这为物质封装、递送、双相反应器等领域提供了重要的发展机遇。在本文中，我们总结了近年来基于主-客体相互作用构筑超分子界面体系的研究进展，并对其制备方法、功能和应用进行了概述。

关键词：液-液界面自组装主-客体化学微胶囊