US-Egypt Cooperative Research: Role of the Interface in the Reinforcement of Nanofilled Polymer Composites

说明：该奖项旨在支持乔治亚州亚特兰大市佐治亚理工学院纺织与纤维工程系Haskel Beckham博士与埃及赫尔万大学化学系Mohamed a . Sharaf博士之间的合作研究项目。制备纳米级填料增强聚合物复合材料，利用固体核磁共振（NMR）研究填料-聚合物界面内的分子结构和动力学。与微米级填料增强的聚合物相比，纳米级填料增强的聚合物表现出显著增强的强度。由于颗粒尺寸小，界面体积足够大，先进的固态核磁共振技术可以用于原位研究。二氧化硅颗粒将通过控制尺寸和表面处理来制备，以便掺入聚（二甲基硅氧烷）的非晶基质和聚（乙烯）的半晶基质中。表面处理将改变本质上亲水的二氧化硅表面，使其具有不同程度的疏水性和与两种基质聚合物的相容性。固体核磁共振将用于检查界面分子结构和动力学。纳米复合材料还将通过微观方法和力学测试方法进行表征。该项目的结果将允许在纳米填充聚合物复合材料中构建分子结构/性能关系。这种关系可用于改善现有材料（如轮胎）的性能，以及为新应用（如运输或建筑中的高强度纤维）设计新的填料增强材料。本提案涉及一个重要的和当前的问题，即界面在填充物增强中的作用是弹性体和纳米复合材料社区感兴趣的。填充纳米粒子的聚合物有许多潜在的应用。佐治亚理工学院和赫尔万大学的设施足以进行拟议的研究，通过他们的合作，研究人员有能力准备和研究新材料。乔治亚理工学院拥有使用固态核磁共振的设备和专业知识。这项研究涉及到聚合物动力学研究的一种非常基本的方法，但pi在材料的技术方面知识渊博。该项目将促进美国和埃及之间的科学合作。美国学生将在这个项目中发挥作用，并将进一步为他们成为独立科学家做准备。这个项目应该培养出训练有素、多学科的学生。该项目得到了美国-埃及联合基金项目的支持，该项目向两国的科学家和工程师提供赠款，以开展这些合作活动。

0318536BeckhamDescription: This award is to support a cooperative research project between Dr. Haskel Beckham, Department of Textile and Fiber Engineering, Georgia Institute of Technology, Atlanta, Georgia and Dr. Mohamed A. Sharaf, Department of Chemistry, Helwan University, Helwan, Egypt. Nanoscopic-filler-reinforced polymer composites will be prepared for solid-state nuclear magnetic resonance (NMR) investigation of the molecular structure and dynamics within the filler-polymer interphase. Polymers reinforced with nanometer-sized filler particles exhibit significantly enhanced strength compared to those reinforced with micrometer-sized fillers. Due to the small particle size, the interfacial volume is sufficiently high that advanced solid-state NMR techniques may be used for in situ studies. Silica particles will be prepared with controlled size and surface treatment for incorporation into a noncrystalline matrix of poly (dimethylsiloxane) and also into a semicrystalline matrix of poly (ethylene). The surface treatment will modify the intrinsically hydrophilic silica surface to varying degrees of hydrophobicity and compatibility with each of the two matrix polymers. Solid-state NMR will be used to examine the interfacial molecular structure and dynamics. The nanocomposites will also be characterized by microscopic methods and by mechanical testing methods. The results from this project will allow construction of molecular structure/property relationships in nanofilled polymer composites. Such relationships can be used to improve properties of existing materials (e.g., tires), and the design of new filler reinforced materials for novel applications (e.g., high-strength fibers in transportation or architecture). Scope: This proposal deals with an important and current issue as the role of the interface in filler reinforcement is of interest to the elastomer and nanocomposite communities. There are many potential applications for polymers filled with nanoparticles. The facilities at both Georgia Tech. And Helwan University are adequate for conducting the proposed research and, through their collaboration, the investigators have the ability to prepare and study novel materials. The facilities and expertise to use solid state NMR are present at Georgia Tech. The research involves a very fundamental approach to the study of polymer dynamics but the PIs are knowledgeable in the technological aspects of the materials. The project will foster scientific collaboration between the US and Egypt. U.S. students will have roles in this project, and will further their preparation to be independent scientists. The project should result in well-trained, multi-disciplinary, students. This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.