Synthesis and Solution Chemistry of Dimeric Surface Active Agents - Enhancement of Surface Activity, Solubilization, and Rheology.

二聚表面活性剂的合成和溶液化学 - 表面活性、增溶和流变学的增强。

• 批准号: RGPIN-2018-06055
• 负责人: Marangoni, Gerrard
• 金额: $ 2.04万
• 依托单位: St. Francis Xavier University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714056
• 关键词: Synthesis; Solution; Chemistry; Dimeric; Surface

The use of surfactants (short for surface-active-agents) in chemical applications has gained significant and varied interest over the last few decades. In addition to their common use as detergents and emulsifiers, surfactants have been employed as a reaction medium for the synthesis of nanoparticles, improved drug delivery systems, and in new high-performance paints and coatings. Conventionally, surfactants consist of a single hydrophobic tail (generally a hydrocarbon) and a strongly polar or ionic headgroup. Over the past 6 years, our NSERC Discovery Grants (DG) program at StFX University has synthesized novel amphiphiles containing multiple headgroups (so-called gemini and other multi-headed surfactants), utilizing versatile building blocks (e.g., pentaerythritol and amino acids). Positive research outcomes from this program are the link that exists between the chemical modification of the surfactant structure and the change in the solution performance of the surfactant that results. This lab is currently synthesizing surfactants that have superior hard water tolerance (no soap scum and good foaming ability in hard water) and excellent detergency/emulsification properties as a result of this research. Projects undertaken in this lab fall into one or more of the following themes: 1. The synthesis of new surfactants; 2. A fundamental understanding of the molecular nature of the self-assembly process; 3. Applications of multi-nuclear nmr spectroscopy in probing the molecular structure of micellar systems and polymer- surfactant complexes; and 4. Microscopic examination of unusual and large surfactant assemblies formed through altering the kosmotropic-chaotropic balance in the surfactant molecules. This NSERC DG funded research will continue to investigate fundamental chemical and commercially important aspects of surfactant aggregation. An area of focus will be the synthesis of asymmetric gemini surfactants (twin-headed, twin-tailed surfactants with an unequal tail length) and related compounds, and the measurement of their solution properties. We will also determine the fundamental solution properties of mixtures of zwitterionic surfactants and gemini surfactants with other surfactants and polymers. The objectives of the program are a better understanding of surfactant chemical structure/performance by understanding the how the variation in the surfactant structure changes the subtle balance of forces responsible for their aggregation into simple, spherical micelles, worm-like micelles, and giant vesicles. UG and Masters's students working on these projects will be trained in surfactant syntheses, have hands-on experience with a 400 MHz nmr, a light scattering instrument, surface tensiometers, rheometers, will build their own ion-specific electrodes, and will be trained in a highly structured, ISO-like research environment.

在过去的几十年中，在化学应用中使用表面活性剂（表面活性代理）在化学应用中引起了巨大的兴趣。除了普遍用作洗涤剂和乳化剂外，表面活性剂还被用作合成纳米颗粒，改善药物输送系统以及新的高性能油漆和涂料的反应培养基。 通常，表面活性剂由单个疏水尾（通常是烃）和强极或离子头组组成。 在过去的6年中，我们在STFX大学的NSERC发现补助金（DG）计划合成了新的两亲物，其中包含多个头组（所谓的Gemini和其他多头表面活性剂），利用多功能的构件（例如，五颗刺激醇和氨基酸）。 该程序的积极研究结果是表面活性剂结构的化学修饰与产生表面活性剂的溶液性能的变化之间存在的联系。 该实验室目前正在合成具有优势硬水量的表面活性剂（在硬水中没有肥皂浮渣和良好的泡沫能力），并且由于这项研究而具有出色的洗涤性/乳化性能。 在本实验室中进行的项目属于以下一个或多个主题： 1。新表面活性剂的合成； 2。对自组装过程的分子性质的基本理解； 3。多核NMR光谱法在探测胶束系统和聚合物表面活性剂复合物的分子结构中的应用；和 4。通过改变表面活性剂分子中的野兽 - 核酸平衡而形成的异常和大表面活性剂组件的微观检查。 这项NSERC DG资助的研究将继续研究表面活性剂聚集的基本化学和商业上重要方面。聚焦区域将是合成不对称的双子表面活性剂（双头，双尾表面活性剂，具有不相等的尾部长度）和相关化合物，以及其溶液特性的测量。 我们还将确定Zwitterionic表面活性剂和双子表面活性剂与其他表面活性剂和聚合物混合物的基本溶液特性。 该程序的目标是更好地理解表面活性剂化学结构/性能，通过了解表面活性剂结构的变化如何改变负责其聚集的力的微妙平衡变成简单的球形胶束，类似蠕虫的胶束和巨型囊泡。 UG和Masters的学生从事这些项目的工作将接受表面活性剂合成的培训，具有400 MHz NMR的动手经验，一种光散射乐器，表面张力仪，流变仪，将构建自己的离子特异性电极，并将在高度结构化的ISO型研究环境中训练。