Scattering from Shear-Ordered Dispersions
نویسنده
چکیده
Rheology is commonly used as a tool for analytics and quality control in latex technology. As soon as flow becomes essential for the structure measured in a scattering experiment we call it scattering from shear-ordered dispersions or rheologic scattering. In this paper it is shown that the structure of concentrated dispersions can with advantage be studied by scattering experiments. Theoretical and experimental aspects as well as examples of small-angle synchrotron x-ray and neutron scattering from colloidal dispersions, presented in the paper, are closely related to rheology. Zusammenfassung: Rheologie wird in der Latextechnologie für analytische Zwecke und zur Qualitätskontrolle eingesetzt. Sobald durch Fliessen in einem Streuexperiment die Struktur einer Dispersion beeinflusst wird, sprechen wir von „Streuung durch schergeordnete Dispersionen“ oder „Rheologischer Streuung“. In dieser Arbeit wird gezeigt, dass die Struktur von Dispersionen vorteilhaft durch Streuexperimente untersucht werden kann. Es werden theoretische und experimentelle Aspekte der Synchrotronröntgenund Neutronenstreuung von konzentrierten Dispersionen behandelt, die eng mit der Rheologie verwandt sind. Résumé: La rhéologie est communément employée comme outil de contrôle de qualité et d’analyses dans la technologie des latex. Aussitôt que l’écoulement devient essentiel pour la structure mesurée lors d’une expérience de diffusion, nous l’appelons diffusion à partir de dispersions ordonnées par cisaillement ou diffusion rhéologique. Dans cet article, il est démontré que la structure de dispersions concentrées peut être avantageusement étudiée à l’aide d’expériences de diffusion. Des aspects théoriques et expérimentaux, ainsi que des exemples de diffusion de neutrons et de rayons X synchrotron aux petits angles par des dispersions colloïdales présentés dans cet article, sont intimement reliés à la rhéologie.
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