在水性三相系统的同一个连续相中,不同相的稳定滴之间的相互作用
Do-Nhu-Trang Nguyen1, Léa Waldmann2, Valérie Ravaine2
1IMMM, UMR 6283 CNRS - Le Mans University, Avenue Olivier Messiaen, Le Mans 72085 cedex 9, France. lazhar.benyahia@univ-lemans.fr.
Soft matter
|April 2, 2024
概括
混合了水性双相系统 (水中的水乳液) 与和凝滴. 添加了微凝,并观察到滴滴凝聚,形成简乌斯型滴和弦,影响界面张力.
科学领域:
- 合体和接口科学科学
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
背景情况:
- 水在水 (W/W) 乳液,或水性双相系统,是由水中的不兼容聚合物的相分离形成的.
- 这些系统通过将成分封装在分散的水滴中,为分隔和局部反应提供了潜在的潜力.
- 稳定和操纵W / W乳液对于先进的应用至关重要.
研究的目的:
- 研究含有不同聚合物 (德克斯和鱼类凝) 的 W/W 乳液滴的相互作用和凝聚行为.
- 研究双性微凝对这些混合乳液的稳定性和界面特性的影响.
- 了解复杂结构的形成,如简斯滴和滴串.
主要方法:
- 制备两种不同的 W/W 乳液:一种用德克斯 (DEX) 滴,另一种用鱼类凝 (GEL) 滴,两者均分散在聚乙烯氧化物连续相中.
- 介绍双型微凝 (MG),由DEX组成,与聚N-异烯胺接种.
- 同焦点扫描激光显微镜用于观察混合时的滴滴相互作用,凝聚和结构形成.
- 测量接触角度以量化带有和没有微凝的相之间的界面张力.
主要成果:
- 两种稳定的W/W乳液的温和混合导致DEX和GEL滴在接触时立即凝聚在一起.
- 观察到含有DEX和GEL分区的Janus型液滴的形成,在接口上没有微凝.
- 这些Janus滴进一步结合到交替的DEX和GEL滴的链条中.
- 微凝影响了相之间的接触角度,表明对界面张力有影响.
结论:
- 在W/W乳液中的德克斯和鱼类凝滴在接触时很容易凝聚在一起,形成Janus型结构.
- 双基微凝在调节这些复杂乳液的界面特性和稳定性方面发挥着作用.
- 这些发现表明,一种方法可以从简单的W/W乳液中创建复杂的层次结构,用于封装和反应控制的潜在应用.
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