Functionalisation of Natural Deep Eutectic Solvents (NADES) by Means of Self-Assembly

天然深共晶溶剂(NADES)由于其一般的生物亲和性，是一类有趣的溶剂，可以通过选择其组成来很大程度上调整其溶剂性质。通过在它们中形成自组装聚集体进行功能化，可以使它们对许多潜在的应用更具吸引力。通过这样做，人们可以控制性质，如增溶或流变性。然而，到目前为止，NADE在物理化学方面往往表现不佳，其中许多都存在高粘度。因此，这项提案的第一个目标是通过彻底和系统地调查各种NADE的相行为来改变这种情况，重点是开发低粘度体系，因为高粘度往往阻碍它们的实际应用。对于最有趣的NADE，我们将研究一系列(生物)表面活性剂，它们具有不同的头基胶束结构(主要通过光、X射线和中子散射)和胶束形成的热力学(ITC、CMC)，目的是识别和量化表面活性剂分子基序的亲溶剂和憎溶剂性质。对于这些表面活性剂体系，我们还将确定典型油和活化剂的增溶性能，因为这通常是使用表面活性剂的一个关键方面。下一步，两亲共聚物的自组装将被研究，从而导致更大规模的结构。由于聚合物在NADS中的溶解度尚不清楚，首先我们必须确定不同聚合物的溶解度，将它们分为可溶(A)和不溶(B)均聚物。在此基础上，我们将合成AB和BAB类型的两亲性嵌段共聚物，并研究它们在纳米粒子中的自组装性能，特别是形成的结构。BAB类共聚物可作为纳米粒子的流变性改进剂，并可通过自组装和网络形成来控制其粘度。用于自组装研究的低粘度纳米粒子也将被用于研究它们的纳米结构，特别是利用中子衍射实验(这是与澳大利亚合作伙伴密切合作的)，因为根据它们的组成，它们可能在流体状态下具有或多或少明显的内部结构。因此，该项目的一个关键目标将是确定NADS流体纳米结构与其促进自组装能力之间的关系，以及自组装聚集体的结构可能如何与NADS的纳米结构相关。总而言之，该项目应提供在不同的低粘度NADE中进行自组装的基本原理，在此基础上，可以在NADE中为低和高相对分子质量的两亲分子进行量身定制的自组装，并使其适应给定NADE的分子结构。

Natural Deep Eutectic Solvents (NADES), due to their generally biofriendly character, are an interesting class of solvents that can be tuned largely with respect to their solvent properties by choice of their components. They can be made even more attractive for many potential applications by functionalisation via formation of self-assembled aggregates in them. By doing so one can control properties like solubilisation or rheological properties. However, so far NADES are often poorly characterised in physico-chemical terms and many of them suffer from high viscosity. Therefore, the first objective of this proposal is to change this by a thorough and systematic investigation of the phase behaviour of a large variety of NADES with a focus on developing low-viscous systems, as high viscosity is often preventing their practical application. For the most interesting NADES we will study for a range of (bio)surfactants, with different head groups micelle structure (mainly by light, x-ray, and neutron scattering) and thermodynamics of micelle formation (ITC, cmc), with the aim of identifying and quantifying solvophilic and solvophobic properties of the molecular motifs of the surfactants. For these surfactant systems we will also determine the solubilisation properties for typical oils and active agents, as this is typically a key aspect to employing surfactants. In a next step, self-assembly by amphiphilic copolymers is to be studied that leads to larger scale structuring. As polymer solubility in NADES is little known yet, first we will have to determine the solubility of different polymers to group them into soluble (A) and insoluble (B) homopolymers. Based on that knowledge amphiphilic block copolymers of AB and BAB type will be synthesized and their self-assembly properties in NADES will be studied, with a particular focus on the structures formed. The BAB-type copolymers should function as rheological modifiers for NADES and allow controlling their viscosity by self-assembly and network formation. The low viscous NADES employed for the self-assembly studies, will also become studied with respect to their nanostructure, in particular employing neutron diffraction experiments (this in close cooperation with the Australian partners), as depending on their composition, they may possess a more or less pronounced internal structure in the fluid state. A key objective of the project then will be to determine relations between the NADES fluid nanostructure and their ability to promote self-assembly, and how the structure of the self-assembled aggregates may be related to the nanostructure of the NADES. In summary, this project shall deliver the basic principles of self-assembly in different low viscous NADES, based on which tailored self-assembly in NADES for low and high Mw amphiphiles can be done, and which is adapted to the molecular structure of a given NADES.