Dynamic Mechanical Materials for Orthotic and Prosthetic Applications

PI: Weder， Christoph和Rowan， StuartProposal Number: 08281555聚合物材料被用于许多矫形器和假肢设备，例如从踝足矫形器到假肢到神经电极。重要的活动集中在开发被称为“主动”、“智能”或“智能”的新型医疗设备上，例如依靠弹性致动器增强膝关节伸展的膝-踝-足矫形器，允许生长中的儿童伸展的可调节和可扩展假体，以及用于治疗脊柱侧凸的主动支架系统。相当有趣的是，这些新设备中使用的聚合物仅仅起到被动作用。具有可电开关机械性能的自适应聚合物将对矫形器和假肢设备的发展产生巨大影响，允许更简单，更紧凑的设计和增强的功能。本项目是一个跨学科的研究项目，致力于设计、制造、研究和应用一种新型的具有可控机械性能的合成聚合物纳米复合材料。目标材料模仿了海参深层真皮的结构和开关机制，并建立在该团队最近在化学反应、动态机械材料开发方面的成功基础上。所提出的纳米复合材料将由低模量基质聚合物和刚性纳米纤维组成，并用电活性分子修饰。这些分子的电子控制开关状态控制着纤维-纤维和纤维-基质的相互作用，从而控制着材料的整体机械性能。联合来自超分子化学、高分子科学与工程、骨科与康复等领域的专业研究人员，拟议的研究将包括(i)新型自适应纳米复合材料的设计、合成和研究，（ii）结合流变学研究和理论模型，对这些自适应材料的结构-性能关系进行预测性理解。（iii）基于新聚合物的机电元件的制造和测试，以及（iv）后者在“智能”支撑系统中用于动态主干控制。这项研究还补充了将研究和教育结合起来的教育因素，并在本科和研究生两级提供令人兴奋的经验。跨学科性质和综合研究方法将为学生提供不同寻常的广泛教育。综合研究和教育的主要方法是项目研究小组，其中包括少数民族高中生、本科生和研究生以及教师。少数民族高中学生将通过与郊区学区的互动而融入其中。其他元素包括与俄亥俄州东北部可持续发展企业家（E4S）倡议的Cleveland+ Biomimicry设计协作项目合作的开创性外展活动。知识价值：鉴于其示范性和基础性的跨学科研究项目将为未来基于活性纳米结构的先进功能材料的设计、合成和制造提供广泛的知识基础。具有电开关机械性能的聚合物材料的开发是一项突破性的成就，目标材料和器件将实现一系列技术相关应用。最初的目标应用是具有可控特性的矫形器，但这种新材料还可以实现许多其他重要应用，例如自适应防护服和主动减振系统。更广泛的影响：拟议的研究将产生具有巨大应用潜力的先进聚合物的蓝图。综合研究方法将为学生提供广泛的教育经验。高中和本科的研究和推广活动旨在增加工程中代表性不足的少数民族的比例，将研究和教育结合起来，提供一个令人兴奋的学习环境，并为研究生研究人员创造教学机会。与E4S的伙伴关系将加强对当地企业家的科学和技术教育，这些企业家有兴趣在该地区为Biomimicry建立社会和知识基础设施。

PI: Weder, Christoph and Rowan, StuartProposal Number: 0828155Polymeric materials are used in many orthotic and prosthetic devices - examples range from ankle-foot orthoses to prosthetic limbs to neural electrodes. Significant activities are focused on the development of new medical devices which are referred to as 'active', 'smart', or 'intelligent', for example knee-ankle-foot orthoses that rely on elastic actuators to enhance knee extension, adjustable and expandable prostheses that permit expansion for growing children, and active brace systems for the treatment of scoliosis. Rather interestingly, the polymers employed in these new devices merely serve a passive role. Adaptive polymers with electrically switchable mechanical properties would have a tremendous impact on the development of orthotic and prosthetic devices, allowing for simpler and more compact design and enhanced functionality. Proposed is an interdisciplinary research program focused on the design, fabrication, investi-gation and application of a novel family of synthetic polymer nanocomposites with electrically controllable mechanical properties. The targeted materials mimic the architecture and switching mechanism found in the deep dermis of sea cucumbers and build on the team's recent success in the development of chemo-responsive, dynamic mechanical materials. The proposed nano-composites will be comprised of a low-modulus matrix polymer and rigid nanofibers, which are decorated with electroactive molecules. The electrically-controlled switching state of these molecules governs fiber-fiber and fiber-matrix interactions and thereby the overall mechanical properties of the material. Uniting researchers with expertise in supramolecular chemistry, polymer science and engineering, and orthopaedics and rehabilitation, the proposed research will embrace (i) the design, synthesis and investigation of novel adaptive nanocomposites, (ii) the combination of rheological studies and theoretical models to develop a predictive understanding for the structure-property relationship of these adaptive materials, (iii) the fabrication and testing of electromechanical elements based on the new polymers, and (iv) the use of the latter in 'smart' brace systems for dynamic trunk control. The research is complemented with educational elements that amalgamate research and education and provide stimulating experiences at both the undergraduate and graduate levels. The interdisciplinary nature and the integrative research approach will provide students with an unusually broad education. The main approach to integrated research and education are Project Research Teams, which include minority high school students, undergraduate and graduate students, and faculty. Minority high school students will be integrated through interactions with a suburban school district. Other elements include a pioneering outreach activity in collaboration with the Cleveland+ Biomimicry Design Collaborative, a program of the Northeast Ohio Entrepreneurs for Sustainability (E4S) initiative. Intellectual merit: On account of its exemplary and fundamental character the proposed interdisciplinary research program will provide a broad intellectual basis for the future design, synthesis and manufacturing of advanced functional materials based on active nanostructures. The development of polymer materials with electrically switchable mechanical properties is a breakthrough achievement and the targeted materials and devices will enable a range of technologically relevant applications. The initially targeted applications are orthotic devices with controllable characteristics, but the novel materials also enable many other important applications, for example adaptive protective clothing, and active vibration dampening systems. Broader impact: The proposed research will yield blueprints for advanced polymers with a substantial application potential. The integrated research approach will provide students with broad educational experiences. The high-school and undergraduate research and outreach activities are designed to increase the fraction of underrepresented minorities in engineering, to integrate research and education, to provide an exciting learning environment, and to create teaching opportunities for graduate researchers. The partnership with E4S will enhance the scientific and technological education of local entrepreneurs that are interested in building the social and knowledge infrastructure for Biomimicry in the region.