Study of the hydration of superplasticizer-cement pastes with optical spectroscopy
- Chemical admixtures like superplasticizers or stabilizing agents are of ever increasing importance for modern concrete technology. Although such admixtures have meanwhile become common practice in many applications of concrete technology, the understanding of these highly complex systems is still limited and the relevant parameters, which predominantly control the interaction between the superplasticizer and the cement components, have not been identified yet. Optical methods have been successfully used for the analysis and monitoring of the interactions between a broad variety of nanoscale and molecular systems like nanoparticles of various chemical composition and different types of organic ligands or biomolecules. This encouraged us to assess the potential of these methods, and particularly reflectance and fluorescence measurements, for the study of the interactions that occur at the interface between particle or hydrate surfaces and the fluid phase at a very early stage ofChemical admixtures like superplasticizers or stabilizing agents are of ever increasing importance for modern concrete technology. Although such admixtures have meanwhile become common practice in many applications of concrete technology, the understanding of these highly complex systems is still limited and the relevant parameters, which predominantly control the interaction between the superplasticizer and the cement components, have not been identified yet. Optical methods have been successfully used for the analysis and monitoring of the interactions between a broad variety of nanoscale and molecular systems like nanoparticles of various chemical composition and different types of organic ligands or biomolecules. This encouraged us to assess the potential of these methods, and particularly reflectance and fluorescence measurements, for the study of the interactions that occur at the interface between particle or hydrate surfaces and the fluid phase at a very early stage of concrete formation. Special emphasis is dedicated to search for and identify differences between commonly used superplasticizers. Here, we focus on hydration effects using commercial comb shape polycarboxylate ethers (PCEs) with different charge densities, which are known to allow a very low water/cement ratio (w/c of 0.20 or less) while maintaining good workability. Based upon changes of the intensity of the reflectance and fluorescence signal and spectral effects of a dye, acting as optical reporter, a model for the interactions of dye, PCE molecules and cement nanoparticles in the very first phase of cement hydration is derived…
Autor*innen: | Alejandra Ramirez Caro, Jutta Pauli |
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Koautor*innen: | Elena Artemeva, Eugeny Ermilov, Claudia Crasselt, Julia StrohORCiD, Berta Mota Gasso, Wolfram SchmidtORCiD, Ute Resch-GengerORCiD |
Dokumenttyp: | Posterpräsentation |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2017 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten | |
Freie Schlagwörter: | Cement hydration; Optical spectroscopy; Superplasticizers |
Veranstaltung: | Gesellschaft Deutscher Chemiker-Analytische Chemie-Anakon 2017 |
Veranstaltungsort: | Tübingen, Germany |
Beginndatum der Veranstaltung: | 03.04.2017 |
Enddatum der Veranstaltung: | 06.04.2017 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 19.04.2017 |
Referierte Publikation: | Nein |