Smart dispersion: Validation of OCT and impedance spectroscopy as solutions for in-situ dispersion analysis of CNP/EP-composites

Publikationstyp
Journal Article
Publikationsdatum
2018-09
Sprache
English
Author
Meeuw, Hauke orcid-logo
Körbelin, Johann 
von Bernstorff, Daniel 
Augustin, Till orcid-logo
Liebig, Wilfried V. orcid-logo
Fiedler, Bodo orcid-logo
Institut
Kunststoffe und Verbundwerkstoffe M-11 
TORE-URI
http://hdl.handle.net/11420/2106
Enthalten in
Materialia 
Volume
1
Start Page
185
End Page
197
Citation
Materialia (1): 185-197 (2018-09)
Publisher DOI
10.1016/j.mtla.2018.06.002
Scopus ID
2-s2.0-85060674129
© 2018 Acta Materialia Inc. In this study, we demonstrate the applicability of three-roll milling (TRM) process for carbon nanotube-epoxy dispersion in industrial scale and two methods to characterize the dispersion quality based on optical coherence tomography (OCT) and impedance spectroscopy were utilized. These methods are easily applicable for industrial continuous TRM dispersion process monitoring. Modeling impedance spectra with equivalent circuit enhances the possibility to quantify the grade of dispersion. We monitored the dispersion development over a complete seven step three-roll mill process for several batches. The gained results are in good accordance to the particle size measurements by grindometry. Results show, on the one hand, that the real part of impedance undergoes a minimum during processing. The most homogeneous dispersion state is not the favorable for gaining electrical conductive materials. On the other hand, imaginary part of impedance undergoes a maximum. High reactance correlates with small particle sizes as well as homogeneous distribution. A developed model from impedance spectra leads to an improved understanding of network formation. OCT results allow a qualitative analysis of the dispersion and detection of in-homogeneous agglomerate sizes.
More Funding Information
The authors thank the German Research Foundation (DFG, project “Multifunktionale Komposite - Gedruckte Elektronik zur strukturintegrierten Zustandsüberwachung von Faser-Kunststoff-Verbunden” - FI 688/9-1) for financial support of this project. Moreover, the authors are grateful to OCSiAl for providing the SWCNT, Hexion Specialty Chemicals for providing the used resins and curing agents and Thorlabs for providing the OCT-devices and the great support with the OCT measurements. Finally we thank EXAKT Advanced Technologies for their technical support with the three-roll-mill.