Collaborative Research: DMREF: Designing Linked Gel Networks with Tunable Valence

这项研究的目标是设计出具有可控机械和光学性能的凝胶材料，该研究得到了DMREF（设计材料革命和工程我们的未来）奖的支持。胶体凝胶是由微小颗粒（胶体）组成的结合的三维网络，其空间组织和连通性导致了广泛应用的特性的独特组合。该项目将产生使用计算机模拟和设计基于其组成胶体及其相互作用的材料的新方法。研究人员将开发软的、可加工的凝胶，这种凝胶与光的相互作用方式通常与硬固体和材料有关，可以模拟天然蛋白质网络的机械功能，以稳定合成细胞。该团队开发的仿真软件将作为开源代码共享。该奖项将通过指导和暑期研究经验，支持社区大学生向四年制STEM学位课程过渡。凝胶网络在长度尺度上的动态连通性和组织决定了它们的物理性质，从而推动了适用于不同凝胶成分的结构设计原则的发展。凝胶将由定义良好的星形聚合物和配体功能化纳米晶体组装而成，为此，将开发并验证一种统一的粗粒度建模方案，该方案将构建块视为具有离散结合位点的片状胶体。链接策略，其中大分子或纳米晶体可逆地连接双功能分子，提供宏观控制的最近邻的数量和模块化的可调性的组成，结构，和由此产生的性质。这一策略和相关的设计原则将被推进到指导水凝胶的力学性能，等离子体纳米晶体凝胶的光学性能，以及通过调节连接剂与胶体的比例和组分的性质来控制混合网络的相行为的机械光学响应。该项目将利用动态共价键网络的制造和建模以及通过考虑共振激发下纳米粒子偶极子的互极化来计算结构复杂组件的光学响应方面的最新进展。将合成、装配和表征与理论和建模紧密结合，将提供通过使用这些混合结构基序可以实现的行为范围的全貌。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of the research supported by this Designing Materials to Revolutionize and Engineer our Future (DMREF) award is to design gel materials with controlled mechanical and optical properties. Colloidal gels are bonded, three-dimensional networks of tiny particles (colloids) whose spatial organization and connectivity result in distinctive combinations of properties useful for wide-ranging applications. The project will result in new ways to use computers to simulate and design materials based on their component colloids and their interactions. The investigators will develop soft, processable gels that interact with light in ways typically associated with hard solids and materials that could emulate the mechanical function of natural protein networks to stabilize synthetic cells. Simulation software developed by the team will be shared as open-source code. The award will support the transition of community college students to four-year STEM degree programs through mentorship and summer research experiences.The dynamic connectivity and organization of gel networks across length scales determine their physical properties, motivating the development of structural design principles applicable to diverse gel compositions. Gels will be assembled from well-defined star-polymers and ligand-functionalized nanocrystals, for which a unified coarse-grained modeling scheme that treats the building blocks as patchy colloids with discrete binding sites will be developed and validated. A linker strategy, in which macromers or nanocrystals are reversibly connected by bifunctional molecules, offers macroscopic control over the number of nearest neighbors and modular tunability of composition, structure, and resulting properties. This strategy and the associated design principles will be advanced to direct the mechanical properties of hydrogels, optical properties of plasmonic nanocrystal gels, and the mechano-optical response of hybrid networks by controlling the phase behavior through modulating linker-to-colloid ratio and properties of the components. The project will leverage recent progress in making and modeling networks with dynamic covalent bonding and in computing the optical response of structurally complex assemblies by considering the mutual polarization of nanoparticle dipoles under resonant excitation. Tight integration of synthesis, assembly, and characterization with theory and modeling will give a full picture of the range of behaviors that can be achieved through use of these hybrid structural motifs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.