Influence of Double Network, Internetwork Connectivity and Sacrificial Bonds on the Frictional Characteristics of Double Network Hydrogels: Experiments and Modeling

双网络、网络连通性和牺牲键对双网络水凝胶摩擦特性的影响：实验和建模

基本信息

批准号：
2154530
负责人：
Rosa Espinosa-Marzal
金额：
$ 42.43万
依托单位：
University of Illinois at Urbana-Champaign
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2023
资助国家：
美国
起止时间：
2023-01-01 至 2025-12-31
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2154530&HistoricalAwards=false
关键词：
Influence Double Network Internetwork Connectivity

项目摘要

This grant will support research that will advance the knowledge related to a structure-property relation for double network hydrogels, promoting the progress of science. The exceptional lubrication behavior of biological tribosystems stems from its biphasic composition, a complex macromolecular network with a water-based lubricant. As a prominent example, articular cartilage balances lubricity with strength. To date, there is an urgent need to generate tribological understanding and models for novel biomaterials that can serve as replacement for cartilage. Double network (DN) hydrogels consist of two interpenetrating polymer network that resemble cartilage, are strong and tough, and have thus emerged as promising biomaterials. This research will advance the understanding of the mechanics associated with DN hydrogels, and specifically how double networks afford control of friction. The implications of this work go beyond fundamentals of soft matter tribology and extend to biomedical applications and soft robotics, where the processes occurring at the migrating hydrogel interface are relevant. Furthermore, the collaborative project will help develop the workforce in the U.S., broaden the participation of underrepresented groups in research, and positively impact engineering education.The overall objective of this research is to provide a fundamental understanding of the relation between microstructure of DN hydrogels and their frictional characteristics via experiments and modeling. Two major lines of research are proposed here: one combining physically and chemically crosslinked networks and a second one combining two chemically crosslinked networks, which lead to intrinsically different microstructures. The intellectual merit of this research will include: (1) thorough data of friction, structural, and mechanical properties of DN hydrogels as a function of composition via (novel and improved) experimental toolsets and a new mechanics model to quantify friction; (2) advances in the fundamental understanding of the effect of double network, sacrificial bonds, internetwork connections and charge on frictional dissipation mechanisms; and (3) discovery of hydrogel materials, capable of achieving low friction coefficients and augmented wear resistance through the precise control of their microstructure. To examine lubrication mechanisms, friction, adhesion and rheological measurements will be carried out on hydrogels to probe multiple dissipation mechanisms. The comparison between experimental and modeling results will enable us to elucidate the underlying mechanisms.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.

这笔赠款将支持研究，以推进与双网络水凝胶结构-性能关系相关的知识，促进科学进步。生物摩擦系统的卓越润滑行为源于其双相成分，即具有水基润滑剂的复杂大分子网络。一个突出的例子是，关节软骨平衡了润滑性和强度。迄今为止，迫切需要对可替代软骨的新型生物材料产生摩擦学理解和模型。双网络（DN）水凝胶由两个类似于软骨的互穿聚合物网络组成，坚固而坚韧，因此成为有前途的生物材料。这项研究将增进对 DN 水凝胶相关力学的理解，特别是双网络如何提供摩擦控制。这项工作的意义超出了软物质摩擦学的基础知识，并扩展到生物医学应用和软机器人技术，其中发生在迁移水凝胶界面的过程是相关的。此外，该合作项目将有助于发展美国的劳动力，扩大代表性不足的群体对研究的参与，并对工程教育产生积极影响。这项研究的总体目标是提供对 DN 水凝胶微观结构与通过实验和建模获得它们的摩擦特性。这里提出了两条主要研究方向：一是结合物理和化学交联网络，二是结合两种化学交联网络，从而产生本质上不同的微观结构。这项研究的智力价值将包括：（1）通过（新颖和改进的）实验工具集和量化摩擦的新力学模型，获得 DN 水凝胶作为成分函数的摩擦、结构和机械性能的全面数据； (2) 对双网络、牺牲键、网络连接和电荷对摩擦耗散机制的影响的基本认识取得进展；（3）发现水凝胶材料，能够通过精确控制其微观结构来实现低摩擦系数和增强耐磨性。为了检查润滑机制，将对水凝胶进行摩擦、粘附和流变测量，以探讨多种耗散机制。实验结果和建模结果之间的比较将使我们能够阐明潜在的机制。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。