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

由设计材料革新和设计我们的未来(DMREF)奖项支持的研究目标是设计具有可控机械和光学性能的凝胶材料。胶体凝胶是由微小颗粒(胶体)组成的粘合的三维网络，其空间组织和连通性导致了可用于广泛应用的各种特性的独特组合。该项目将带来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。研究人员将开发柔软、可加工的凝胶，这种凝胶与光相互作用的方式通常与硬固体和材料有关，可以模仿天然蛋白质网络的机械功能来稳定合成细胞。该团队开发的模拟软件将作为开源代码共享。该奖项将通过导师指导和暑期研究经验，支持社区大学学生过渡到四年制STEM学位课程。凝胶网络的动态连通性和组织决定了它们的物理性质，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的纳米晶体组装而成，为此将开发并验证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。大分子或纳米晶体通过双功能分子可逆连接的连接子策略，提供了对最近邻分子数量的宏观控制以及组成、结构和结果性质的模块化可调整性。这一策略和相关的设计原则将被用来指导水凝胶的力学性质、等离子体纳米晶凝胶的光学性质以及杂化网络的机械光学响应，通过调节连接物与胶体的比例和组成的性质来控制相行为。该项目将利用动态共价键网络的制作和建模方面的最新进展，以及通过考虑共振激发下纳米粒子偶极的相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、组装和表征与理论和建模紧密结合，将全面了解通过使用这些混合结构主题可以实现的行为范围。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.