Abstract
In situ measurements are an increasingly important tool to inform the complex relationship between nanoscale properties and macroscopic material measurements. Knowledge of these phenomena can be used to develop new materials to meet the performance demands of next generation technologies. Conductive complex fluids have emerged as an area of research where the electrical and mechanical properties are key design parameters. To study the relationship between microstructure, conductivity, and rheology, we have developed a small angle neutron scattering (SANS) compatible Couette rheological geometry capable of making impedance spectroscopy measurements under continuous shear. We have also mounted this geometry on a commercial strain controlled rheometer with a modified forced convection oven. In this manuscript, we introduce the simultaneous measurement of impedance spectroscopy, rheological properties and SANS data. We describe the validation of this dielectric RheoSANS instrument and demonstrate its operation using two systems - an ion gel comprising Pluronic® surfactant and ionic liquid, ethyl-ammonium nitrate, and poly(3-hexylthiophene) organogel prepared in a mixture of hexadecane and dichlorobenzene. In both systems, we use this new measurement capability to study the microstructural state of these materials under two different protocols. By monitoring their dielectric rheology at the same time as the SANS measurement, we demonstrate the capacity to directly probe structure-property relationships inherent to the macroscopic material response.
| Original language | English (US) |
|---|---|
| Article number | 105115 |
| Journal | Review of Scientific Instruments |
| Volume | 88 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 1 2017 |
Funding
The authors would like to acknowledge funding from the NIST Center for Neutron Research cooperative Agreement Nos. 70NANB12H239 and 70NANB15H260, the NCNR CMS grant for partial funding during this time as well as the National Research Council for support. This work benefitted from SasView software, originally developed by the DANSE project under NSF Award No. DMR-0520547. We would also like to thank Greg Newbloom and Ru Chen for providing useful discussions and samples for the case studies in this manuscript. Finally, we would like to thank Cedric Gagnon and Jeff Krzywon for their assistance in preparing the sample environment. Certain commercial equipment, instruments, or materials are identified in this paper to specify the experimental procedure adequately. Such identification is neither intended to imply recommendation or endorsement by the National Institute of Standards and Technology nor intended to imply that the materials or equipment identified are necessarily the best available for the purpose.
ASJC Scopus subject areas
- Instrumentation