Establishing the principles and demonstrating the unique properties of novel reconfigurable nano- and microparticle structures bound by liquid bridges

建立原理并展示由液桥结合的新型可重构纳米和微米颗粒结构的独特性质

• 批准号: 1604116
• 负责人: Orlin Velev
• 金额: $ 29.36万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1604116&HistoricalAwards=false
• 关键词: Establishing; principles; demonstrating; unique; properties

CBET - 1604116PI: Velev, Orlin D.Many technologically important materials are made by assembling colloidal particles into structures that often start with simple chains or filaments. A variety of techniques are available to assemble particles into chains, but so far it has proven challenging to make permanent chains that are flexible. This project will explore a new method for making highly flexible particle chains based on capillary attractions between particles coated with liquid lipids, which is broadly similar to the way sandcastles are bound by small volumes of liquid. The particles assemble due to liquid bridges that form between them when they are aligned by a magnetic field. Because the bridges are fluid, the resulting filaments are extremely flexible. The goal of the project is to characterize the capillary binding between colloidal particles and demonstrate that it can be used to make new classes of nanoparticle assemblies in the form of filaments, networks, and gels. Results of the project will provide new opportunities for assembling soft multifunctional materials whose properties can be dynamically controlled, such as temperature-responsive and self-repairing gels and novel 3D printing inks. The unusual characteristics of the materials that will be made in the project will provide a unique opportunity for science demonstrations to high-school students how nanoscale structures affect macroscopic properties. The project will provide training grounds for students to participate in hands-on research in nanoscale engineeringSuper-paramagnetic nanoparticles will be dispersed into aqueous solutions of fatty acid salts, which completely wet the particle's surface. Fatty acid molecules condense onto the surface to form liquid-like shells. The liquid-coated nanoparticles are assembled by applying an external magnetic field to align the particles into filaments, which remain intact after the external field is removed. The physical properties of filaments and other structures formed by the nanocapillary binding of isotropic and patchy particles will be investigated as a function of bridge fluidity, type and composition of the surface-condensed lipid. The project will focus on understanding the fundamental origins and measuring the magnitude of the capillary bridging force, on characterizing and modeling the properties of the assembled filaments, on using the assembly method to make hierarchical nano-microstructures, and on developing novel thixotropic gels. Such gels, based on silicone beads capillary bound by a liquid silicone precursor, will be tested as new material for 3D printing of flexible, porous and biologically compatible structures.

CBET -1604116 PI：Velev，Orlin D.许多技术上重要的材料是通过将胶体颗粒组装成结构制成的，这些结构通常从简单的链或细丝开始。 有多种技术可用于将颗粒组装成链，但到目前为止，制造柔性的永久链已被证明具有挑战性。 该项目将探索一种新的方法，基于涂有液体脂质的颗粒之间的毛细吸引力来制造高度灵活的颗粒链，这与沙堡被小体积液体束缚的方式大致相似。当粒子被磁场排列时，它们之间形成的液体桥会使粒子聚集。 由于桥是流体，因此产生的细丝非常柔韧。该项目的目标是表征胶体颗粒之间的毛细管结合，并证明它可用于制造细丝，网络和凝胶形式的新型纳米颗粒组装体。该项目的结果将为组装柔性多功能材料提供新的机会，这些材料的性能可以动态控制，例如温度响应和自修复凝胶以及新型3D打印油墨。 将在该项目中制造的材料的不寻常特性将为高中学生提供一个独特的科学演示机会，让他们了解纳米结构如何影响宏观特性。该项目将为学生提供培训场所，让他们参与纳米工程的实践研究。超顺磁性纳米颗粒将分散在脂肪酸盐的水溶液中，完全润湿颗粒的表面。 脂肪酸分子凝聚在表面上形成液体状的外壳。 通过施加外部磁场将颗粒排列成细丝来组装液体涂覆的纳米颗粒，这些细丝在去除外部磁场后保持完整。 将研究由各向同性和片状颗粒的纳米毛细管结合形成的细丝和其他结构的物理性质作为桥流动性、表面凝聚脂质的类型和组成的函数。 该项目将侧重于了解的基本起源和测量的毛细管桥接力的大小，对组装长丝的特性进行表征和建模，使用组装方法，使层次纳米微结构，并开发新型触变凝胶。这种凝胶基于由液体硅前体毛细管结合的硅珠，将作为柔性，多孔和生物相容性结构的3D打印新材料进行测试。