Abstract
In the present work, electrochemical impedance spectroscopy (EIS) was employed for cure monitoring of bisphenol A/F based epoxy resin-polyoxypropylenediamine hardener systems modified with various concentrations of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) ionic liquid (IL). These systems exhibited phase separation induced by an increase in the molar mass through the curing of the resin. The progress of the curing process was accompanied by a steady increase of impedance for all types of samples, as expected, due to the increasing viscosity of the medium for increased degree of cure. The results were compared to those of unmodified resin-hardener systems. The sensitivity of EIS as a cure monitoring technique increased dramatically with the addition of the IL. The cure kinetics of the epoxy resin was characterized by differential scanning calorimetry and the data were used to create a model for comparison with the EIS results. The change of the ionic conductivity during curing as a function of IL concentration and the effect of IL loading on mechanical properties of the resin were also studied. We demonstrate that [BMIM]BF4 loading of 5wt.% increased the room temperature ionic conductivity of the fully cured product by an order of magnitude with only a 2.5% reduction in compression strength from that of pure epoxy.
| Original language | English |
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| Title of host publication | 32nd Technical Conference of the American Society for Composites 2017 |
| Editors | Johnathan Goodsell, Wenbin Yu, R. Byron Pipes |
| Publisher | DEStech Publications Inc. |
| Pages | 1570-1585 |
| Number of pages | 16 |
| ISBN (Electronic) | 9781510853065 |
| State | Published - 2017 |
| Event | 32nd Technical Conference of the American Society for Composites 2017 - West Lafayette, United States Duration: Oct 23 2017 → Oct 25 2017 |
Publication series
| Name | 32nd Technical Conference of the American Society for Composites 2017 |
|---|---|
| Volume | 3 |
Conference
| Conference | 32nd Technical Conference of the American Society for Composites 2017 |
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| Country/Territory | United States |
| City | West Lafayette |
| Period | 10/23/17 → 10/25/17 |
Funding
The authors gratefully acknowledge Dr. Kane Jennings’ and Dr. Peter Pintauro’s laboratories in Chemical Engineering Department at Vanderbilt University, for granting access to Gamry Instruments CMS300 Impedance system and DSC TA Instruments Q200, respectively. LP would also like to acknowledge Vanderbilt University for their Graduate students financial support.