Fracture in Nanostructured Polymeric Materials

纳米结构聚合物材料的断裂

• 批准号: 0704192
• 负责人: Frank Bates
• 金额: $ 56万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0704192&HistoricalAwards=false
• 关键词: Fracture; Nanostructured; Polymeric; Materials

TECHNICAL SUMMARY:This research program will explore the connections between the molecular architecture of block copolymers and the mechanical properties of the resulting nanostructured plastics. Mutiblock copolymers will be synthesized using controlled polymerization techniques augmented by chemical modification such as catalytic hydrogenation. These compounds will be investigated in undiluted and blended forms. Self-assembly into ordered and disordered microphase separated materials will be characterized by a compliment of experimental techniques such as small-angle X-ray and neutron scattering, electron microscopy, dynamic mechanical spectroscopy, and birefringence analysis. Tensile and impact mechanical properties will be evaluated and correlated with the morphological structure and molecular architecture. Selected block copolymer and blend specimens will be partially voided by chemical etching or selective solvent extraction resulting in nanoporous monoliths that will be subjected to fracture analysis. New strategies will be developed to toughen these intrinsically fragile porous compounds, through a combination of multiblock copolymer design, strategic placement of rubbery, glassy, and semicrystalline blocks within the matrix material, and blending of multiblock copolymers with synergistic molecular architectures.NON-TECHNICAL SUMMARY:Perhaps no other class of material properties has a greater impact on the utilization of plastics than mechanical robustness. This research program will explore the connections between the molecular structure of polymer molecules, produced by controlled synthetic chemistry methods, and the fracture behavior of the resulting materials. This work will impact the application of new plastics in commercially important products ranging from optical media such as laptop computer screen, new types of membranes that may find uses in fuel cells and batteries, and inexpensive and light plastics used extensively in the automotive industry. This program affords outstanding opportunities to enthuse and inform students at all levels of education in science and engineering through interactive programs at the University, local schools, and regional museums.

技术摘要：该研究计划将探索嵌段共聚物的分子结构与所得纳米结构塑料的机械性能之间的联系。多嵌段共聚物将使用受控聚合技术合成，并通过化学改性（例如催化氢化）增强。这些化合物将以未稀释和混合的形式进行研究。自组装成有序和无序微相分离材料的特征将通过小角度 X 射线和中子散射、电子显微镜、动态机械光谱和双折射分析等实验技术的补充来表征。将评估拉伸和冲击机械性能并将其与形态结构和分子结构相关联。选定的嵌段共聚物和共混物样本将通过化学蚀刻或选择性溶剂萃取而部分无效，从而形成纳米多孔整体材料，并进行断裂分析。将开发新的策略来增韧这些本质上脆弱的多孔化合物，通过结合多嵌段共聚物设计，在基体材料中战略性地放置橡胶状、玻璃状和半结晶嵌段，以及将多嵌段共聚物与协同分子结构混合。非技术摘要：也许没有其他类别的材料特性对塑料的利用具有更大的影响 比机械鲁棒性。该研究计划将探索通过受控合成化学方法生产的聚合物分子的分子结构与所得材料的断裂行为之间的联系。这项工作将影响新塑料在重要商业产品中的应用，包括笔记本电脑屏幕等光学介质、可能用于燃料电池和蓄电池的新型薄膜，以及汽车工业中广泛使用的廉价轻质塑料。该项目提供了绝佳的机会，通过大学、当地学校和地区博物馆的互动项目，激发各级科学与工程教育学生的热情并为其提供知识。