Synergistic Physiochemical Properties of Macromolecule-Metal Complexes

高分子-金属配合物的协同理化性质

• 批准号: 0320980
• 负责人: Laurence Belfiore
• 金额: --
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0320980&HistoricalAwards=false
• 关键词: Synergistic; Physiochemical; Properties; Macromolecule; Metal

This research activity focuses on the development of macromolecule-metal complexes that exhibit synergistic thermophysical properties, and the spectroscopic detection of the underlying complexation. Metal cations from the d-block and the f-block in the Periodic Table act like magnets that induce functional polymers to occupy vacant sites in the first-shell coordination sphere of the metal center. Consequently, the formation of self-assembled mobility-restricting nanoclusters in solid polymeric complexes allows one to design materials that can withstand larger forces before failure occurs and higher temperatures prior to viscous flow or thermal degradation. This is an extension of supramolecular design that represents a new frontier in interdisciplinary macromolecular science and engineering. Organic-inorganic hybrid materials are expected to contribute significantly to the state-of-the-art in nanotechnology, and yield devices with unusually new and useful properties via molecular engineering. At the molecular level, high-resolution carbon-13 solid state NMR and Fourier transform infrared spectroscopies will be used to probe microenvironmental factors that influence metal-based coordination-driven micromixing. When paramagnetic transition metal salts form complexes with the polymers of interest, magnetic susceptibility measurements will be performed to investigate the spin-glass nature of these nanoclusters that are responsible for unique macroscopic physical properties. Temperature dependence of magnetic susceptibilities in the vicinity of the glass transition is unprecedented. The principal investigator has contributed significantly to the current state of knowledge of macromolecule-metal complexes, yet scientific literature databases suggest that there has not been much activity at the spectroscopic level to support the proposed models for metal-ligand interaction, particularly when the dissociation of these complexes coincides with the glass transition process.Metal-based coordination-driven interactions at the molecular level can be exploited in several practical areas of science and technology. For example, it is possible to (i) compatibilize polymers that are immiscible in the absence of the inorganic component, (ii) separate mixtures of alkenes and alkanes (i.e., olefin/paraffin blends) via precipitation of transition metal pi-complexes, (iii) modify the viscosity (i.e., viscosification) of polymer solutions by bridging chains and increasing their molecular weight, (iv) induce gelation and simulate the response of artificial muscles to neural impulses via cyclic expansion and contraction of gelatinous materials that contain trapped metal cations in the presence of AC electric fields, and (v) remove heavy metal contaminants from wastewater streams via water-soluble polymers that contain functional groups which act as magnets for these toxic compounds. The fundamental studies under investigation in this research project will have a direct influence on the design and use of macromolecule-metal complexes in these five areas of practical interest.

该研究活动的重点是开发具有协同热物理性质的大分子-金属络合物，以及对潜在络合作用的光谱检测。 来自周期表中d-区和f-区的金属阳离子像磁铁一样作用，诱导功能聚合物占据金属中心的第一壳配位层中的空位。 因此，在固体聚合物复合物中形成自组装的限制迁移率的纳米团簇允许人们设计能够在失效发生之前承受更大的力和在粘性流动或热降解之前承受更高温度的材料。 这是超分子设计的延伸，代表了跨学科大分子科学和工程的新前沿。 有机-无机杂化材料有望对纳米技术的发展做出重大贡献，并通过分子工程产生具有异常新颖和有用特性的器件。 在分子水平上，高分辨率碳-13固态NMR和傅里叶变换红外光谱将用于探测影响基于金属的配位驱动微观混合的微环境因素。 当顺磁性过渡金属盐与感兴趣的聚合物形成复合物时，将进行磁化率测量以研究这些纳米团簇的自旋玻璃性质，这些纳米团簇负责独特的宏观物理性质。 在玻璃化转变附近的磁化率的温度依赖性是前所未有的。 主要研究者对大分子-金属络合物的当前知识状态做出了重大贡献，但科学文献数据库表明，在光谱水平上没有太多的活动来支持金属-配体相互作用的拟议模型，特别是当这些络合物的解离与玻璃化转变过程一致时。分子水平上的驱动相互作用可以在科学和技术的几个实际领域中得到利用。 例如，可以（i）使在不存在无机组分的情况下不混溶的聚合物相容，（ii）分离烯烃和烷烃的混合物（即，烯烃/链烷烃共混物），（iii）改变粘度（即，通过桥接链和增加它们的分子量来使聚合物溶液增粘），（iv）通过在AC电场的存在下含有捕获的金属阳离子的凝胶状材料的循环膨胀和收缩来诱导凝胶化和模拟人造肌肉对神经脉冲的响应，和（v）通过水-可溶性聚合物，含有作为这些有毒化合物的磁体的官能团。本研究项目中的基础研究将直接影响这五个实际感兴趣的领域中高分子-金属配合物的设计和使用。