Collaborative Research: Understanding and Controlling Chemo-Mechanical Properties of Metal Coordinating Polymer and Inorganic Nanoparticle Composites

1605943/1605699 Holten-Andersen，Niels/Tracy，Joseph B.金属配位蛋白和无机表面之间的界面在自然界中发现的一些最显著的复合材料的机械性能中起着至关重要的作用。从贻贝的水下粘附胶到珍珠贝坚韧的贝壳，越来越多的人发现，金属结合蛋白与无机表面之间的粘性相互作用控制着它们的机械性能。将研究一种更简单的合成系统，其中无机纳米颗粒作为金属结合聚合物的动态桥梁，以从自然中学习复合材料设计原理，并将这些原理应用于设计具有受控和响应的机械性能的新材料。这些材料的潜在应用包括药物输送、自我修复复合材料和3D打印。PIS将基于这些生物启发的复合材料开发学习模块，用于推广活动，以提高公众对纳米技术的认识，并招收更多的学生进入STEM职业生涯。该项目的目标是利用生物启发的金属配位聚合物-纳米颗粒(MCP-NP)复合材料作为模型系统，了解如何通过受控的MCP-NP界面动力学来设计新的力学。与以往具有金属离子交联剂的MCP材料不同，NPs将作为超分子交联剂，每个NP结合的配体数量可调。系统的化学和物理参数将被调整，以获得对MCP-NP界面上的分子相互作用如何影响MCP-NP复合材料的整体力学性能的基本了解，并展示对机械响应的控制。与传统的工程复合材料和其他复合水凝胶相比，MCP-NP复合材料具有粘弹性和可调的界面结合。已经选择了磁性和光学响应性NPs，以允许使用光场和磁场进行远程加热。该项目将提供对复合材料界面动力学的更深层次的了解，这对于改进复合材料力学性能的工程至关重要，例如自我修复和可调的流固转变。关于MCP-NP界面化学和机械响应之间关系的见解将适用于其他具有动态界面的复合体系。

1605943/1605699Holten-Andersen, Niels/Tracy, Joseph B. Interfaces between metal coordinating proteins and inorganic surfaces have a vital role in the mechanical properties of some of the most remarkable composites found in nature. From the underwater adhesive glues of mussels to the tough shells of nacre, sticky interactions between metal binding proteins and inorganic surfaces have increasingly been found to control their mechanical properties. A simpler, synthetic system, where inorganic nanoparticles serve as dynamic bridges for metal binding polymers, will be investigated to learn principles of composite material design from nature and to apply these principles for engineering new materials with controlled and responsive mechanical properties. Potential applications for these materials include drug delivery, self-healing composites, and 3D printing. The PIs will develop learning modules based on these bio-inspired composites for use in outreach activities to increase public awareness about nanotechnology and to recruit more students into STEM careers.The goal of this project is to utilize bio-inspired metal coordinating polymer-nanoparticle (MCP-NP) composites as model systems for understanding how to engineer novel mechanics via controlled MCP-NP interfacial dynamics. In contrast to previous MCP materials with metal ion crosslinkers, NPs will serve as supramolecular crosslinkers, with a tunable number of ligands bound per NP. Chemical and physical parameters of the system will be adjusted to obtain a fundamental understanding of how molecular interactions at MCP-NP interfaces affect the bulk mechanical properties of MCP-NP composites and to demonstrate control over the mechanical response. In comparison with traditional engineering composites and other composite hydrogels, MCP-NP composites are viscoelastic and have tunable interfacial bonding. Magnetically and optically responsive NPs have been selected to also allow remote heating using light and magnetic fields. This project will provide a deeper understanding of composite interfacial dynamics critical for improved engineering of composite mechanical properties, such as self-healing and tunable fluid-solid transitions. Insights about the relationship between chemistry at MCP-NP interfaces and the mechanical response will be applicable to other composite systems with dynamic interfaces.