EAGER: Fabrication and Characterization of 3D Ceramic-Coated Polymer Scaffolds

非技术描述：EAGER项目利用新的沉积技术，研究沉积在聚合物结构上的陶瓷膜的形成，以更好地了解陶瓷的组成和微观结构如何取决于沉积条件。这一信息对于能够通过用陶瓷膜涂覆聚合物模板来制造三维陶瓷结构至关重要。三维陶瓷结构具有广泛的应用，从用于能量转换或化学处理的催化剂载体到医学植入物和生物研究。这项工作的目标应用是模仿骨的化学成分、微观结构、孔隙率和表面形态的陶瓷结构。这些结构具有与骨相似的特性，正被用于进行基础研究，例如肿瘤细胞迁移和侵袭的研究以及药物筛选。研究生和本科生积极参与这项多学科的工作，获得对他们未来的成功至关重要的技能。技术专长：EAGER基金研究控制磷酸钙（CAP）薄膜沉积在2D和3D聚氨酯（PUR）模板上形成具有类似骨骼特性的结构的加工/性能/性能关系的基本机制。对于大多数应用，陶瓷的表面组成和微观结构以及结构的孔径/孔隙率显著影响多孔陶瓷结构的性能。3D打印是一种令人兴奋的新方法，可以制造具有特定孔隙率和孔径的聚合物结构。共形CAP涂层使用低温原子层沉积工艺沉积。该项目涉及的科学问题包括2012年NSF主办的研讨会期间确定的陶瓷科学八大挑战中的两个：1）预测和控制异质微观结构，以及2）控制远离平衡的陶瓷。Rogers教授使用硅上的2D结构，使用与制造3D结构相同的工艺制造，研究CAP/PUR系统的化学成分，微观结构和机械性能如何随加工条件而变化。由于合成温度较低，所沉积的CAP薄膜为非晶。沉积后退火是用来研究如何非晶CAP结晶作为温度曲线和整体热负荷的函数。固有的非平衡快速热退火工艺有利于在薄CAP膜中形成相和微结构，这些相和微结构是通过对块体材料的热控制处理无法获得的。该项目涉及的主题范围（硬材料和软材料，加工，表征，计算机编程，反应器设计/建造，2D与3D材料）使项目团队的研究生和本科生接触到学术和工业研究以及解决问题的许多方面。他们通过这个项目获得的技能将使他们在整个职业生涯中受益。

NON-TECHNICAL DESCRIPTION: This EAGER project capitalizes on new deposition technologies and investigates the formation of ceramic films deposited onto polymer structures to better understand how the composition and microstructure of the ceramic depends on the deposition conditions. This information is critical to be able to fabricate three-dimensional ceramic structures by coating a polymer template with a ceramic film. Three-dimensional ceramic structures have a wide variety of applications, from catalyst supports for energy conversion or chemical processing to medical implants and biological studies. The target application for this work is ceramic structures that mimic the chemical composition, microstructure, porosity, and surface morphology of bone. With properties similar to bone, these structures are being used to perform fundamental studies, such as investigation of tumor cell migration and invasion as well as drug screening. Graduate and undergraduate students are actively involved in this multidisciplinary work, gaining skills important to their future success.TECHNICAL DETAILS: This EAGER grant investigates fundamental mechanisms controlling the processing/property/performance relationships of calcium phosphate (CAP) films deposited onto 2D and 3D polyurethane (PUR) templates to form structures with properties similar to bone. For most applications, the surface composition and microstructure of the ceramic, and the pore size/porosity of the structure significantly impact a porous ceramic structure's performance. 3D printing is an exciting new way to fabricate polymer structures with defined porosity and pore size. The conformal CAP coatings are deposited using a low temperature atomic layer deposition process. The scientific issues involved in this project encompass two of the eight grand challenges for ceramic science that were identified during a 2012 NSF-sponsored workshop: 1) predicting and controlling heterogeneous microstructures, and 2) control of ceramics far from equilibrium. Prof. Rogers uses 2D structures on silicon, fabricated using a process identical to that used to fabricate the 3D structure, to study how the chemical composition, microstructure, and mechanical properties of the CAP/PUR system evolve as a function of processing conditions. The as-deposited CAP films are amorphous due to the low synthesis temperature. Post-deposition annealing is used to investigate how the amorphous CAP crystallizes as a function of temperature profile and overall heat duty. The inherently non-equilibrium rapid thermal annealing process facilitates the formation of phases and microstructures in the thin CAP films that are not attainable through thermodynamically-controlled processing of bulk materials. The breadth of topics involved in this project (hard and soft materials, processing, characterization, computer programming, reactor design/construction, 2D vs. 3D materials) exposes the graduate and undergraduate students on the project team to many aspects of academic and industrial research and problem solving. The skills they attain through this project will benefit them throughout their career.