Mechanics of Colloidal Membranes

这个项目的目标是研究胶体膜的机理-由丝状病毒或DNA折叠束等胶体颗粒组成的膜。这些膜具有让人想起细胞膜的类似生命的能力，例如自我愈合或自发组装成复杂可控形状的能力。材料工程的发现使二十世纪的许多技术进步成为可能。耐蚀不锈钢、尼龙、半导体和集成电路等合成聚合物，以及显示器用液晶的发展，都对社会和我们的生活质量产生了深刻的影响。这些进展中的每一项都需要必要的理论框架和实验技术来理解和控制无生命物质的材料特性。今天，我们正处于生物启发材料工程的新时代的开始，因为现在刚刚有可能创造和控制由生物成分组成的具有生物物质独特性质的材料。PI将开发理论和计算工具来预测和控制胶体膜的机理，以及胶体膜的形状如何取决于实验条件。这种研究方法有可能在物理、数学和工程界之间架起一座桥梁。与这项研究相关的YouTube教育视频也将被制作成面向公众的宣传视频。胶体膜因其作为高度可重构的微观结构以及作为生物材料(如脂质双层膜)的类似物的潜力而很有前途。虽然胶体膜与脂类双层膜有许多共同的性质，如流动性，但它们也有自己独特的方面，包括具有边缘的低能量成本。对这些物体的力学研究仍处于初级阶段，需要多学科的方法，包括固体力学、统计力学、液晶物理和微分几何的元素。研究小组将执行三项具体任务：(I)计算平盘状膜到波纹螺旋片和扭曲带的熵驱动或手性驱动不稳定性和随后的非线性演化；(Ii)计算膜盘和螺旋带的力与拉伸关系；以及(Iii)预测和分类更复杂拓扑的胶体膜的形状，如猫状结构和其他观察到的多孔结构。

The goal of this project is to study the mechanics of colloidal membranes---membranes comprised of colloidal particles such as filamentous viruses or DNA origami bundles. These membranes have life-like abilities reminiscent of cell membranes, such as the ability to heal themselves or assemble spontaneously into complex and controllable shapes. Many of the technological advances of the twentieth century were made possible by discoveries in materials engineering. The development of corrosion-resistant stainless steel, synthetic polymers such as nylon, semiconductors and integrated circuits, and liquid crystals used in displays have all had a profound impact on society and our quality of life. Each of these advances required the theoretical framework and experimental techniques necessary to understand and control the material properties of inanimate matter. Today we are at the beginning of a new era of bio-inspired materials engineering, as it is now just becoming possible to create and control materials consisting of biological components and with the distinctive properties of living matter. The PIs will develop the theoretical and computational tools to predict and control the mechanics of colloidal membranes and how colloidal membrane shape depends on the experimental conditions. The research approach has the potential to bridge the physics, math and engineering communities. Educational YouTube videos related to the research will also be created for outreach to the public.Colloidal membranes are promising for their potential as highly reconfigurable microscopic structures, and as analogs to biological materials such as lipid bilayer membranes. While colloidal membranes share many properties with lipid bilayer membranes, such as their fluidity, they also have their own unique aspects, including a low energy cost for having edges. The study of the mechanics of these objects is still in its infancy, and requires a multidisciplinary approach including elements from solid mechanics, statistical mechanics, liquid crystal physics, and differential geometry. The research team will carry out three specific tasks: (i) calculate the entropy-driven or chirality-driven instability and subsequent nonlinear evolution of flat disk-shaped membranes to rippled helical sheets and twisted ribbons, (ii) calculate the force vs. extension relation for membrane disks and helicoidal ribbons, and (iii) predict and classify the shapes of colloidal membranes of more complex topology, such as catenoids and other observed structures with multiple holes.