Acquisition of a 400-MHz Solid-State NMR Spectrometer for Investigations of Synthetic and Naturally Occurring Polymers

由这项重大研究仪器奖支持的新型400-MHz固态核磁共振(核磁共振)光谱仪将使爱荷华州立大学的一个跨学科研究团队能够以前所未有的细节表征复杂的聚合物材料。特别是多维核磁共振将被应用于提供关于无序大分子固体中分子的化学结构、构象、链段间距离和重定向的详细和定量信息。所获得的见解将为改进材料的合理设计以及控制自然环境中大分子有机物与污染物和营养物质的相互作用奠定基础。具体地说，新的核磁共振仪器将使研究人员能够开展以下方面的研究：1)无定形合成聚合物中的链构象、堆积和动力学，及其对宏观材料性能的影响，包括物理老化；2)含有新的极性、官能化双烯的聚合物的结构和序列分布；3)具有重要技术意义的多相聚合物体系中的纳米结构；4)聚合物与新型低玻璃化温度无机玻璃纳米复合材料中的结构和动力学；5)可再生资源塑料的结构和改进的性能；6)土壤有机质的结构、形成及其对有机和无机污染物吸附的影响；7)土壤固碳机理，可减少大气“温室气体”；8)开发先进的、往往是多维的核磁共振脉冲序列，为有机固体的核磁共振分析提供“武器库”，结构分辨率至少提高三倍。合作使用该仪器的教师的多样性将为化学、材料科学、农学和食品科学的学生提供一个极好的环境，让他们在刺激的跨学科氛围中学习和进行研究。爱荷华州立大学主要研究仪器项目授予爱荷华州立大学的这一奖项支持购买400 MHz核磁共振(核磁共振)仪器。核磁共振是分析复杂有机材料最有效的方法之一。它利用了许多原子核的磁性。这些核磁体充当当地的“间谍”，报告他们的分子环境，他们这样做是对射频脉冲的反应。这些脉冲可以被设计成“梳理”出关于化学结构、关于纳米尺度的区域或关于被研究材料中的节段运动的特定信息。新的核磁共振仪器将帮助研究人员开发具有定制性能的材料，例如脆性较小的可生物降解塑料、用于燃料电池的更好的膜、来自可再生资源的坚固塑料、改进的粘合剂，或在车辆中提供更高燃油效率的轻质材料。它还将增进我们对土壤有机质和化石燃料如何形成的了解，并有助于制定改进的环境清理程序和从大气中隔离“温室气体”的程序。合作使用这一仪器的教师队伍的多样性将为化学、材料科学、农学和食品科学的学生提供一个良好的环境，让他们在刺激的跨学科氛围中学习和开展研究。

The new 400-MHz solid-state nuclear magnetic resonance (NMR) spectrometer supported by this Major Research Instrumentation award will enable an interdisciplinary team of researchers at Iowa State University to characterize complex polymeric materials in unprecedented detail. Multidimensional NMR in particular will be applied to provide detailed and quantitative information on the chemical structure, conformations, inter segmental distances, and reorientations of molecules in disordered macromolecular solids. The insights obtained will be the basis for the rational design of improved materials and for controlling the interactions of macromolecular organic substances in the natural environment with contaminants and nutrients. Specifically, the new NMR instrument will enable the investigators to perform research on: 1) chain conformation, packing, and dynamics in amorphous synthetic polymers, and their effects on macroscopic materials properties, including physical aging; 2) the configuration and sequence distribution of polymers containing new polar, functionalized dienes; 3) nanometer-scale structures in technologically important heterogeneous polymer systems; 4) structure and dynamics in nano-composites of polymers with novel inorganic glasses of low glass-transition temperature; 5) the structure and improved properties of plastics from renewable resources; 6) the structure of soil organic matter, its formation, and its influence on the sorption of organic and inorganic contaminants; 7) mechanisms of carbon sequestration in soil, which can reduce atmospheric "greenhouse gases"; 8) the development of advanced, often multidimensional NMR pulse sequences to provide an "arsenal" for NMR analysis of organic solids with at least three-fold increased structural resolution. The diversity of the faculty collaborating in the use of this instrument will provide an excellent environment for students of chemistry, materials science, agronomy, and food science to learn and perform research in a stimulating interdisciplinary atmosphere.This award from the Major Research Instrumentation program to Iowa State University supports the acquisition of a 400 MHz Nuclear Magnetic Resonance (NMR) instrument. NMR is one of most powerful methods for analyzing complex organic materials. It uses the magnetic properties of the nuclei of many atoms. These nuclear magnets act as local "spies" reporting on their molecular environment, and they do so in response to radio-frequency pulses. These pulses can be designed to "tease out" specific information about the chemical structure, about nanometer-scale domains, or about motions of segments in the material under investigation. The new NMR instrument will help researchers to develop materials with tailored properties, such as less brittle biodegradable plastics, better membranes for use in fuel cells, strong plastics from renewable resources, improved adhesives, or lightweight materials providing increased fuel efficiency in vehicles. It will also enhance our understanding of how soil organic matter and fossil fuels are formed, and aid in the development of improved procedures for environmental clean-up and for the sequestration of "greenhouse gases" from the atmosphere. The diversity of the faculty collaborating in the use of this instrument will provide an excellent environment for students of chemistry, materials science, agronomy, and food science to learn and perform research in a stimulating interdisciplinary atmosphere.