Separation of Complex Materials by Field-Flow Fractionation

这个项目是在分析和表面化学的一般领域和分离科学的子领域。本研究的目的是促进场流分馏（FFF）科学技术及相关方法的持续发展；这项工作将在四个分领域进行。(1)高分子材料的热FFF表征。在这个领域，对热FFF至关重要的潜在热扩散过程将被表征。耦合柱-通道系统将开发使用热FFF和尺寸排除色谱的组合来表征共聚物共混物的组成和分子量分布。热FFF将优化用于高速聚合物分析，并探索该技术对超高分子量聚合物的适用性。(2)高速流/立体（超层）FFF。这项新开发的技术的工作将以优化、校准、扩展范围、提高可重复性、探索实际应用和理解控制这些新系统性能的基本力量为目标进行。(3)分流薄（SPLITT）连续分离池。在这一推力，SPLITT分离的基础上扩散，沉淀和电传输过程将特别强调规模扩大到实际的准备水平进行探索。(4)新的FFF理论和方法。在这里，吉丁斯教授将继续沿着理论和实验路线追求新的FFF技术。将继续注意完善FFF分离的理论基础。这项研究继续了首席研究员通过几种FFF变体对复杂、高分子量材料的分析和制备分离的发展。这些FFF方法中的每一种都具有独特的优势，当与手头的问题适当匹配时，可以提高分析能力。尽管这些技术实施的复杂性迄今为止阻碍了它们的广泛采用，但这些方法的绝对力量使它们明显优于对材料和生物技术过程至关重要的聚合物物质的表征的竞争性方法。FFF技术的继续发展将提供一个强大的分析和准备工具库，供这些技术重要领域使用。此外，Giddings教授继续展示了这些工具的广泛适用性，应该会加快材料和生物科学界对它们的采用。

This project is in the general area of analytical and surface chemistry and in the subfield of separation science. The objective of this research is the continuing development of the science and technology of field-flow fractionation (FFF) and related methods; this work will be carried out in four subareas. (1) Thermal FFF Characterization of Polymeric Materials. In this area, the underlying thermal diffusion processes that are essential to thermal FFF will be characterized. A coupled column- channel system will be developed using a combination of thermal FFF and size exclusion chromatography to characterize the composition and molecular weight distribution of copolymer blends. Thermal FFF will be optimized for high-speed polymer analysis and the applicability of this technique to ultra-high molecular weight polymers will be explored. (2) High Speed Flow/Steric (Hyperlayer) FFF. Work on this recently developed technique will be performed with the objective of optimizing, calibrating, extending the range, improving the repeatability, exploring practical applications, and understanding the basic forces that govern the performance of these new systems. (3) Split-Flow Thin (SPLITT) Continuous Separation Cells. In this thrust, SPLITT separations based on diffusive, sedimentation, and electrical transport processes will be explored with special emphasis on scale-up to a practical preparative level. (4) New FFF Theory and Methodology. Here, Professor Giddings will continue his pursuit of new FFF techniques along both theoretical and experimental lines. Continued attention will be paid to refining the theoretical basis for FFF separations. This research continues the Principal Investigator's development of analytical and preparative separations of complex, high molecular weight materials by several FFF variants. Each of these FFF methods offers unique advantages which, when appropriately matched to the problem at hand, can give rise to enhanced analytical capability. Whereas the complexity of implementation of these techniques has thus far impeded their broad adoption, the sheer power of the methods places them significantly above competitive approaches for the characterization of polymeric substances of key importance to materials and biotechnological processes. The continued development of FFF techniques will provide a formidable arsenal of analytical and preparative tools for use in these technologically important areas. Additionally, Professor Giddings' continued demonstration of the broad applicability of these tools should expedite their adoption by the materials and bioscience communities.