Coupled measurement system for investigation of adsorption and complexing behaviour of polymers and nanoparticles in mortar and concrete: FFF-MALS-ICP-MS

用于研究砂浆和混凝土中聚合物和纳米颗粒的吸附和络合行为的耦合测量系统：FFF-MALS-ICP-MS

• 批准号: 420379123
• 金额: --
• 依托单位: Bauhaus-Universität Weimar
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/420379123?language=en
• 关键词: Coupled; measurement; system; investigation; adsorption

Modern cement-based binder systems are high-performance materials that are characterized by a multi-component composition. During the hardening process many reactions occur simultaneously, for instance solution, nucleation and growth as well as sol-gel reactions. The partially unknown structure of organic admixtures, the complex composition of the entire system and the very small dimensions of the early reaction products make it difficult to study the processes in the early phase of cement hydration. The F.A. Finger Institut für Baustoffkunde (FIB) at the Bauhaus Universität Weimar has been researching these processes on an international level for decades. A coupled measurement system is applied for which is capable of characterizing ions, polymers, complexes, nanoparticles and microparticles of different structure, composition and charge respectively. The system consists of a fractionation module and a detection module. The fractionation module consists of the basic HPLC components pump and autosampler, an asymmetric flux-field flow fractionation channel (AF4 channel) which can be replaced by a GPC/SEC column as well as an AF4 channel with electric field. The separation takes place in an open channel (AF4) with an asymmetrical flow profile depending on the hydrodynamic radii of the particles, whereby particles with small radii elute earlier than larger ones. If an electric field is additionally applied to the hydrodynamic flow profile, the particles are separated according to their electrophoretic mobility. The zeta potential can be calculated by comparing both chromatograms (AF4 and electric-AF4 respectively). The AF4 channel could be replaced by a GPC/SEC column if the molecular mass of pure polymers has to be determined. The detection module consists of a multi-angle laser scattering detector (MALS), a dynamic light scattering detector (DLS), a refractive index detector (RI) and an inductively coupled plasma mass spectrometer (ICP-MS). The MALS is used to determine the gyration radii of the particles, which can be used to calculate the molecular weight of polymers. In combination with static light scattering, the hydrodynamic radius provides important information about the conformation of the polymer and its secondary structure. The special RI detector is a highly concentration-sensitive detector used for quantification of polymers in solution. An inline-coupled ICP-MS possessing low detection limits and high detection speed provides information on the chemical composition of the particles. The transient recording of many mass traces should make it possible to distinguish between the organic and inorganic nature of the particles. The applied coupled measuring system is integrated into the chemical analysis laboratory of the F.A. Finger Institute of building materials and is operated by the Chair of Building Chemistry and Polymer Materials (Prof. Osburg) as well as the Chair of Construction Material Science (Prof. Ludwig).

现代水泥基粘结剂系统是高性能材料，其特点是多组分组成。在硬化过程中，许多反应同时发生，如溶液、成核和生长以及溶胶-凝胶反应。有机外加剂的部分结构未知，整个体系的组成复杂，早期反应产物的尺寸很小，给水泥水化早期过程的研究带来了困难。位于魏玛包豪斯Universität的F.A.芬格研究所（F.A. Finger Institut fr Baustoffkunde， FIB）几十年来一直在国际层面上研究这些过程。本文介绍了一种能够分别表征不同结构、组成和电荷的离子、聚合物、配合物、纳米粒子和微粒的耦合测量系统。该系统由分馏模块和检测模块组成。分选模块由基本HPLC组分泵、自动进样器、可由GPC/SEC柱替代的非对称流场流分选通道（AF4通道）和带电场的AF4通道组成。分离发生在一个开放通道（AF4）中，根据颗粒的流体动力半径，其流动剖面不对称，因此半径小的颗粒比大的颗粒更早被洗脱。如果在流体动力学流动剖面上额外施加电场，则根据其电泳迁移率分离颗粒。zeta电位可以通过比较两种色谱（分别为AF4和电-AF4）来计算。如果要测定纯聚合物的分子质量，可以用GPC/SEC色谱柱代替AF4通道。检测模块由多角度激光散射检测器（MALS）、动态光散射检测器（DLS）、折射率检测器（RI）和电感耦合等离子体质谱计（ICP-MS）组成。MALS用于确定颗粒的旋转半径，该半径可用于计算聚合物的分子量。结合静态光散射，流体动力半径提供了聚合物构象及其二级结构的重要信息。特殊的RI检测器是一种高度浓度敏感的检测器，用于定量溶液中的聚合物。内联耦合ICP-MS具有低检出限和高检测速度，可提供有关颗粒化学成分的信息。许多质量痕迹的瞬态记录应该可以区分粒子的有机性质和无机性质。应用耦合测量系统集成在F.A.芬格建筑材料研究所的化学分析实验室中，由建筑化学和高分子材料系主任（Osburg教授）和建筑材料科学系主任（Ludwig教授）共同操作。