Effects of carbon fillers on the rheology of highly filled liquid-crystal polymer based resins
Document Type
Article
Publication Date
5-5-2008
Department
Department of Chemical Engineering
Abstract
Adding conductive carbon fillers to insulating resins increases the composite electrical and thermal conductivity. Often, enough of a single type of carbon filler is added to achieve the desired conductivity while still allowing the material to be molded into a bipolar plate for a fuel cell. In this study, various amounts of three different carbons (carbon black, synthetic graphite particles, and carbon fiber) were added to Vectra A950RX liquid-crystal polymer. The rheological properties of the resulting single-filler composites were measured. In addition, the rheological properties of composites containing combinations of different carbon fillers were studied via a factorial design. In all cases, the viscosity increased with increasing filler volume fraction and followed a shear-thinning power-law model. The factorial design results indicated that each of the single fillers and all the filler combinations caused a statistically significant increase in the composite viscosity when compared at a shear rate of 500 s-1 or at a stress of 105 Pa. For composites containing synthetic graphite particles and/or carbon fiber, the viscosity variation with the volume fraction of carbon followed a modified Maron-Pierce equation. When compared at a constant volume fraction of carbon, composites containing carbon black showed viscosity enhancement above and beyond that shown by the other composites.
Publication Title
Journal of Applied Polymer Science
Recommended Citation
King, J. A.,
Tambling, T.,
Morrison, F.,
Keith, J.,
Cole, A.,
&
Pagel, R.
(2008).
Effects of carbon fillers on the rheology of highly filled liquid-crystal polymer based resins.
Journal of Applied Polymer Science,
108(3), 1646-1656.
http://doi.org/10.1002/app.27755
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/3519