Design of Tough Resilient Gels Using Adhesive Rigid-Rod Polymers

非技术摘要：该项目将确定最佳的设计参数为强大的，有弹性的聚合物材料，以提高其在广泛的应用，包括作为智能结构材料，可以在失败后愈合，作为受损关节的组织替代品，并作为大规模生产干细胞培养的支架。我们的研究利用蛋白质聚合物的独特功能来创造具有增强韧性和弹性的材料。我们的研究结果将不仅提供优化标准，但将建立分子结构和体积，宏观材料响应之间的关系。在长度尺度之间建立这种联系非常重要，这将使其他学术和工业工程师能够利用我们的工作来解决材料科学中的许多问题。这项研究将使研究生，本科生和社区学院的学生参与材料研究，同时提供最先进的实验和计算方法的实践培训。学生和PI将参加社区外展活动，并访问当地小学，以提高公众对尖端材料科学的理解。技术摘要：该项目将通过建立粘性刚性杆聚合物网络中结构和力学之间的关系，改进强有力的弹性聚合物材料的设计。我们使用一种由丝状细胞蛋白质制成的模型系统，这种蛋白质称为微管，具有我们可以严格控制的化学和机械特性。 在实验上，我们使用聚焦电磁场将局部力施加到这样的网络上来操纵微尺度颗粒，并且我们将颗粒位移与凝胶的局部机械性能联系起来。 与大多数合成系统不同，基于蛋白质的网络是非常刚性的，允许它们保留其初始未加载状态的内在记忆。此外，蛋白质基交联剂是不稳定的：它们的键在力的作用下断裂，但在力被移除时可以改革。这些独特的特征增加了生物材料的韧性和弹性，并允许这种材料“愈合”，即使当它们局部加载到故障。通过实验和模拟，我们的工作将建立材料反应的微观起源，并将指导耐用，自适应和自我修复的生物启发材料的开发。这种材料可以用作人造组织或智能结构材料，其中需要在负载下吸收冲击。这项工作将从事研究生，本科生和社区学院的学生在材料研究。学生和PI将参加当地小学的社区外展活动，以促进公众对尖端材料科学的理解，并将通过出版物，会议和亲自访问当地学校广泛分享我们的成果。

Non-technical Abstract:This project will determine the optimal design parameters for strong, resilient polymeric materials to improve their use in a wide range of applications including as smart structural materials that can heal after failure, as tissue replacements for damaged joints, and as scaffolds for the large-scale manufacture of stem cell cultures. Our study takes advantage of the unique features of protein-based polymers to create materials with enhanced toughness and resiliency. Our results will provide not only optimization criteria, but will establish the relationships between molecular structure and bulk, macroscopic material response. Building such connections between length scales is very important, and will enable other academic and industrial engineers to leverage our work to solve numerous problems in materials science. This study will engage graduate, undergraduate and community college students in materials research, while providing hands on training in state-of-the-art experimental and computational methods. The students and the PI will participate in community outreach events and visits to local elementary schools to advance a public understanding of cutting edge materials science.Technical Abstract:This project will enable the improved design of strong, resilient polymeric materials by establishing the relationships between structure and mechanics in adhesive rigid rod polymer networks. We use a model system made of filamentous cellular proteins called microtubules with chemical and mechanical properties we can tightly control. Experimentally, we apply local forces to such networks using focused electromagnetic fields to manipulate microscale particles and we relate particle displacement to understand the local mechanical properties of the gels. Unlike most synthetic systems, protein-based networks are very rigid allowing them to retain an intrinsic memory of their initial, unloaded state. Moreover, protein-based crosslinkers are labile: their bonds break under force but can reform when the force is removed. These unique features increase biomaterial toughness and resiliency, and allow such materials to 'heal', even when they are locally loaded to failure. Through experimentation and simulation, our work will establish the microscopic origins of material response, and will guide the development of bio-inspired materials that are durable, adaptive, and self-healing. Such materials could be used as artificial tissues or as smart structural materials where shock absorption under loading is required. This work will engage graduate, undergraduate and community college students in materials research. The students and the PI will participate in community outreach events at local elementary schools to advance a public understanding of cutting edge materials science and will share our results broadly through publications, conferences, and in-person visits to local schools.