刚核离子液晶的合成和中形性质
Paul H J Kouwer1, Timothy M Swager
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|October 24, 2007
概括
具有扩展芳香核的新离子液晶表现出可调整的中相,其中一些达到室温液晶性. 混合物具有多种混合性,为需要稳定性和广泛温度范围的应用提供了潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
- 物理化学 物理化学
背景情况:
- 离子液晶 (ILCs) 将离子液体特性与液晶自我组织结合起来.
- 了解结构-属性关系对于设计新的ILC至关重要.
研究的目的:
- 分析新型基于伊米达的具有扩展芳香核的ILC的结构性质关系.
- 为了研究分子结构 (尾巴,核心,替代, counterion) 对 mesophase 行为的影响.
- 探索ILC混合物的混合性和混合行为.
主要方法:
- 一系列基于伊米达的ILCs的合成和表征.
- 对等态性质的研究,包括相位行为和热稳定性.
- 分析ILC混合物以确定可混合性和混合特性.
主要成果:
- 观察到两种截然不同的交叉相位相位相:双层SmA2和单层SmA.
- 中相表现出高热稳定性;通过抑制结晶实现室温液态结晶性.
- ILC混合物表现出理想的可混合性和令人惊的完整阶段脱混合.
结论:
- 分子设计显著影响ILCs的中等态行为和热性质.
- ILC及其混合物展示了潜在应用的调节性质.
- 在混合物中观察到的混合性行为为ILC-ILC相互作用提供了洞察力.
相关概念视频
Molecular and Ionic Solids
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
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Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Liquid–Solid Solutions
The process of a solid dissolving in a liquid to form a solution is governed by the solubility limit, which is the maximum amount of the solid substance, or solute, that can be dissolved in a specific volume of the liquid or solvent. As the solute dissolves, it reaches a point where no more solute can be dissolved at a given temperature - this is known as the saturation point. However, if further solute is added and it manages to dissolve, the solution becomes supersaturated. Supersaturated...
Lattice Energies of Ionic Crystals
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Polymer Classification: Crystallinity
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Recrystallization: Solid–Solution Equilibria
Recrystallization is a purification technique used to separate impurities from solid compounds. In this technique, no chemical reactions occur. Instead, it exploits physical properties only, specifically, the solubility differences between the desired compound and impurities, either at a single temperature or at different temperatures, and under other selected conditions. The solid-solution equilibrium (solubility equilibrium) of each component in the solution represents a binary phase...
Solubility of Ionic Compounds
Solubility is the measure of the maximum amount of solute that can be dissolved in a given quantity of solvent at a given temperature and pressure. Solubility is usually measured in molarity (M) or moles per liter (mol/L). A compound is termed soluble if it dissolves in water.


