JOURNAL OF MOLECULAR LIQUIDS
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2022
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IF 6.633
Xiaomei Pei,Junhui Wu,Xinyuan Zou,Binglei Song,Zhao Chen,Pei Liu,Zhenggang Cui,Ting Pan,Yao Gu
Stimulus-responsive surfactants (N + –C n -N,n = 14 or 16) can stabilize conventional emulsions, Pickering emulsions and oil-in-dispersion emulsions in the presence of oppositely and similarly charged nanoparticles. Rapid demulsification can be successfully achieved by bubbling CO 2 . In the presence of CO 2 , N + –C n -N becomes a hydrophilic Bola-type surfactant, N + –C n -NH + , and is an inferior emulsifier either when used alone or together with charged nanoparticles, resulting in demulsification. In addition, nearly all N + –C n -NH + molecules are present in the aqueous phase after demulsification without contaminating the oil phase. The aqueous phase can be recycled and used again for further emulsification of oils. Compared with the pH responsive systems, there is no accumulation of salt after the gas cycles, and more cycles can be performed. This protocol is a green process and leads to preparation of various temporarily stable emulsions used in oil emulsion transportation, emulsion polymerization, industrial catalysis, nanomaterial synthesis and other fields.
研究领域:
化学工程
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材料科学
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界面科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Yunlei Shi,Dazhen Xiong,Zhiyong Li,Huiyong Wang,Jikuan Qiu,Hucheng Zhang,Jianji Wang
In recent years, metal–organic frameworks (MOFs) have been explored as emulsifiers for the fabrication of Pickering emulsions and then used for hybrid material synthesis and interface catalysis. Nevertheless, stimuli-responsive Pickering emulsions stabilized by MOFs have been rarely reported so far, although they are of great importance for fundamental research studies and practical applications. Herein, for the first time, triethylenetetramine (TETA)-functionalized MOFs (ZIF-90/TETA) have been designed, synthesized, and used for fabricating CO2-/N2-response Pickering emulsions. It is shown that even at the ZIF-90/TETA content of 0.25 wt %, the functional MOF can still efficiently emulsify n-hexane and water to form a high internal phase Pickering emulsion. Importantly, the Pickering emulsion can be easily and reversibly switched between emulsification and demulsification by bubbling of CO2 and N2 alternatively at atmospheric pressure. The possible mechanism of the CO2/N2 switchable emulsion is investigated by zeta potential, water contact angle, interfacial tension, 13C NMR spectroscopy, and an optical microscope. It is found that the acid–base reaction of CO2 with TETA anchored on the surface of ZIF-90 leads to the production of hydrophilic ammonium bicarbonate and carbamate, which results in the emulsification of the Pickering emulsion. However, when N2 is bubbled to remove CO2, the reverse reaction takes place to cause the demulsification of the Pickering emulsion. Moreover, the CO2/N2 switchable Pickering emulsion has been successfully used as a microreactor for Knoevenagel reactions to demonstrate a highly efficient integration of chemical reaction, product separation, and ZIF-90/TETA recycling for a sustainable chemical process.
研究领域:
化学
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材料科学
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胶体科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2021
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IF 9.381
Xinyu Meng,Huan Liu,Xinyu Dong,Qiqi Wang,Yongmei Xia,Xueyi Hu
Polymeric Pickering emulsifiers may bring new insights to emulsion theory and practice due to their soft characters. Herein, a group of soft Pickering emulsifiers, chitosan-casein hydrophobic peptides nanoparticles (CS-CHP NPs) were prepared with a non-covalent anti-solvent procedure. The CS-CHP NPs provided the contact angles of 37.2°-87.4°, stabilizing O/W or W/O emulsions with enhanced thermal stability , endowing the emulsion with pH and CO 2 /N 2 responsiveness. The emulsifying behavior and mechanism presented by CS-CHP NPs were different from that of ordinary hard Pickering emulsifiers, where the appropriate contact angle was 37.2° instead of 87.4° for stabilizing O/W emulsions. Moreover, the nanoparticles possess antioxidant , antibacterial activities and excellent biocompatibility. DPPH and ABTS scavenging activity of the CS-CHP NPs were >220% of that of CS NPs. The last, the emulsion provided high-efficient encapsulation of curcumin , making the soft Pickering emulsifiers a group candidate for drug delivery in food , cosmetics and pharmaceutical industry .
研究领域:
材料科学
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化学工程
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药剂学
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食品科学
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化妆品
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）