Simultaneous Rheoelectric Measurements of Strongly Conductive Complex Fluids
| العنوان: | Simultaneous Rheoelectric Measurements of Strongly Conductive Complex Fluids |
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| المؤلفون: | Ahmed Helal, Thibaut Divoux, Gareth H. McKinley |
| المساهمون: | Massachusetts Institute of Technology (MIT), Centre de Recherche Paul Pascal (CRPP), Université de Bordeaux (UB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), MultiScale Material Science for Energy and Environment, MIT-France seed fund and the CNRS through a PICS-USA scheme (No. 36939). |
| المصدر: | Physical Review Applied Physical Review Applied, American Physical Society, 2016, 6 (064004), pp.1-19. ⟨10.1103/PhysRevApplied.6.064004⟩ |
| بيانات النشر: | HAL CCSD, 2016. |
| سنة النشر: | 2016 |
| مصطلحات موضوعية: | Microstructural evolution, Yield (engineering), Materials science, Rheology measurement, Flow (psychology), FOS: Physical sciences, General Physics and Astronomy, 02 engineering and technology, Condensed Matter - Soft Condensed Matter, 01 natural sciences, Rheology, 0103 physical sciences, Electrical measurements, Composite material, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, Electrical conductor, Complex fluid, [PHYS]Physics [physics], Condensed Matter - Materials Science, Viscoplasticity, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, 3. Good health, Complex fluid systems, Soft Condensed Matter (cond-mat.soft), 0210 nano-technology |
| الوصف: | We introduce a novel apparatus designed for stress-controlled rheometers to perform simultaneous rheological and electrical measurements on strongly conductive complex fluids under shear. By means of a non-toxic liquid metal at room temperature, the electrical connection to the rotating shaft is completed with minimal additional mechanical friction, allowing for simultaneous stress measurements as low as 1 Pa. We use the capabilities of this design to perform an extensive set of rheo-electric experiments on gels formulated from attractive carbon black particles, at concentrations ranging from 4 to 15% wt. First, experiments on gels at rest prepared with different shear history show a robust power-law scaling between the elastic modulus $G'_0$ and the conductivity $\sigma_0$ of the gels, i.e. $G'_0 \sim \sigma_0^\alpha$, with $\alpha =1.65 \pm 0.04$ independently of the gel concentration. Second, conductivity measurements performed simultaneously with creep experiments reveal for the first time that plastic events take place in the bulk while the shear rate decreases as a weak power law of time in the early stage of the experiment. The subsequent evolution of the conductivity and shear rate allows us to propose a local yielding scenario that is in agreement with previous velocimetry measurements. Finally, we determine the constitutive rheological and electrical behavior of carbon black gels. Corrections first introduced for mechanical measurements are carefully extended to electrical measurements to accurately distinguish between bulk and surface contributions to the conductivity. As an illustrative example, we examine the constitutive rheo-electric properties of five carbon black gels of different grades, and demonstrate the relevance of the novel rheo-electric apparatus as a versatile characterization tool for strongly conductive complex fluids and their applications. Comment: 15 pages, 10 figures + supplemental material |
| اللغة: | English |
| تدمد: | 2331-7019 |
| DOI: | 10.1103/PhysRevApplied.6.064004⟩ |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::baf6caa62730d653bd215577cb5de901 https://hal.archives-ouvertes.fr/hal-01417303 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....baf6caa62730d653bd215577cb5de901 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 23317019 |
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| DOI: | 10.1103/PhysRevApplied.6.064004⟩ |