基于pH可切换表面活性剂的微乳液:由合适的酸和引发的微乳化和脱乳化之间的可逆过渡
Bo Zhu1, Hui Chen1, Liwen Shi1,2
1Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical & Materials Engineering, Jiangnan University, Wuxi 214122, P. R. China.
Langmuir : the ACS journal of surfaces and colloids
|November 14, 2024
概括
这项研究引入了使用SDS-C12A的第一个基于表面活性剂的pH可切换微乳液 (SBME),为可回收反应介质等应用实现可逆相过渡.
科学领域:
- 材料科学 材料科学 材料科学
- 合体和表面化学
背景情况:
- 基于pH可切换表面活性剂的微乳液 (SBMEs) 提供可逆相变,这是一个很少报告的现象.
- 通过pH控制微乳液稳定性对于先进的材料应用至关重要.
研究的目的:
- 制造和描述第一个可切换pH的SDS-C12A基微乳液 (SDS-C12A-ME).
- 研究可逆切换的机制和副产品的影响.
- 为了证明SDS-C12A-ME作为可回收反应介质的潜力.
主要方法:
- 使用二甲基硫酸盐和N,N-二甲基二甲基胺的等分混合物制造SDS-C12A-ME.
- 研究由酸和交替引发的可逆切换.
- 副产品 (H2O和盐) 对可逆性的影响的评估.
- 使用甲基甲基酸盐光化学聚合作为模型系统的演示.
主要成果:
- 成功制造了第一个可以切换pH值的SDS-C12A-ME.
- 可逆切换依赖于C12A的质子化/解质子化,影响乳化膜.
- 盐的副产品显著降低了可逆性;与氧化相比,胆氧化增强了切换周期.
- SDS-C12A-ME作为聚合物的可回收反应介质,产生具有可重复分子量和狭窄的多分散性 (PDI ≈ 1.2) 的聚甲酸.
结论:
- 开发的SDS-C12A-ME表现出高效的pH可切换的行为.
- 优化的酸刺激 (例如,HCl-ChOH) 提高了可逆性和循环稳定性.
- 可切换pH值的微乳液是有希望的可回收介质,用于聚合和潜在的其他应用,如药物输送和微反应器.
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