Separation of Complex Materials by Field-Flow Fractionation

这项研究由化学部门的分析和表面化学项目支持，将寻求利用场流分馏技术分离和表征大分子和小颗粒的新方法，这是一项由首席研究员首创的技术。溶剂的交叉流动或交叉力场（流体流动vs.温度，流体流动vs.电场，或流体流动vs.重力）用于根据密度、电迁移率和直径的差异分离分子和颗粒。应用包括制备单分散颗粒和分析混合物。这项研究由化学部的分析和表面化学项目支持，重新支持了首席研究员在分离和分析大分子和颗粒的场流分馏（FFF）方面的工作。FFF基于流体流动和垂直力场（第二流体的流动、重力、热或电场）与待分离混合物的竞争性相互作用分离分子、颗粒或细胞。这与更常见的分离方法形成对比，这些方法依赖于要用固定的选择相分离的物质的化学相互作用。目前的建议侧重于基于热梯度的聚合物和乳液的分离。

This research, supported by the Analytical and Surface Chemistry Program in the Chemistry Division, will seek new ways to separate and characterize large molecules and small particulates using Field Flow Fractionation, a technique pioneered by the principal investigator. Crossed flows of solvents or crossed force fields (fluid flow vs. temperature, fluid flow vs. electric field, or fluid flow vs. gravity) are employed to separate molecules and particulates based on differences in their density, electrical mobility, and diameter. Applications include both preparation of mono-dispersed particulates and analysis of mixtures. %%% This research, supported by the Analytical and Surface Chemistry Program in the Chemistry Division, renews support of the principal investigator's work in field flow fractionation (FFF) for separation and analysis of large molecules and particulates. FFF separates molecules, particulates, or cells based on the competitive interaction of a fluid flow adn a perpendicular force field (flow of a second fluid, gravity, heat, or electric field) with the mixture to be separated. This contrasts with more common separation methods that depend on the chemical interaction of the substances to be separated with a stationary, selective phase. The current proposal focuses on separations of polymers and emulsions, based on thermal gradients.