Synergistic effects of carbon fillers on tensile and impact properties in nylon 6,6 and polycarbonate based resins

Journal of Composite Materials

Hauser

Tomson

et al. 2008

Self Cite

Thermally conductive resins are needed for fuel cell bipolar plates. Varying amounts of three different carbons (carbon black, synthetic graphite particles, and carbon fiber) were added to Vectra A950RX Liquid Crystal Polymer. The resulting single filler composites were tested for thermal conductivity. In addition, the effects of single fillers and combinations of two different carbon fillers were studied via a factorial design. Synthetic graphite caused the largest statistically significant increase in composite through plane and in plane thermal conductivity. Composites containing synthetic graphite/carbon black and synthetic graphite/carbon fiber caused a statistically significant increase in through plane and in plane thermal conductivity.

“…These values are similar to that of the as-received material and prior work [36,37]. For the molded composites containing Fortafil 243, the length was typically 70 mm.…”

Section: Filler Length Aspect Ratio and Orientation Resultsmentioning

confidence: 69%

Synergistic Effects of Carbon Fillers in Thermally Conductive Liquid Crystal Polymer Based Resins

Journal of Composite Materials

Hauser

Tomson

et al. 2008

Self Cite

“…These observations agreed with prior work, and additional photomicrographs have been shown elsewhere. 19,20,[37][38][39][40] Through-plane thermal conductivity results…”

Section: Filler Length Aspect Ratio and Orientation Resultsmentioning

confidence: 99%

“…These values were similar to those of the as-received material and prior work. 37,38 For the injectionmolded composites containing Fortafil 243, the length was typically 70 lm, and the corresponding fiber aspect ratio (length/diameter) was 9. These results agreed with prior work.…”

Section: Filler Length Aspect Ratio and Orientation Resultsmentioning

confidence: 99%

“…These results agreed with prior work. 19,20,37,38 The fillers for the in-plane thermal conductivity samples were primarily oriented in the in-plane thermal conductivity measurement direction, which was induced by the injection-molding process. The fillers in the through-plane samples were primarily oriented transverse to the thermal conductivity measurement direction.…”

Section: Filler Length Aspect Ratio and Orientation Resultsmentioning

confidence: 99%

“…Figure 8 shows that Thermocarb TC-300 synthetic graphite caused the largest increase in the in-plane thermal conductivity. The value increased from 0.99 W m 21 K 21 , which was the in-plane thermal conductivity of the polymer (an anisotropic polymer, so the thermal conductivity was different in the throughplane and in-plane directions), to 38 Factorial design analysis The effects and P values are given in Table VIII, which shows the values for all of the filler combinations. Further investigation of Table VIII yields some important information regarding the effects that the different fillers had on the composite in-plane thermal conductivity.…”

Section: Factorial Design Analysismentioning

confidence: 99%

See 2 more Smart Citations

Effects of carbon fillers on the thermal conductivity of highly filled liquid‐crystal polymer based resins

Hauser

J of Applied Polymer Sci

Pagel

et al. 2008

Self Cite

The thermal conductivity of insulating polymers can be increased by the addition of conductive fillers. One potential market for these thermally conductive resins is for fuel cell bipolar plates. In this study, various amounts of three different carbon fillers (carbon black, synthetic graphite particles, and carbon fiber) were added to Vectra A950RX liquid crystal polymer. Because the resulting composites were anisotropic, they were tested for both through-plane and in-plane thermal conductivities. The effects of single fillers and combinations of the different fillers were studied via a factorial design. Each single filler caused a statistically significant increase in composite through-plane and in-plane thermal conductivities at the 95% confidence level, with synthetic graphite causing the largest increase. All of the composites containing combinations of the different fillers caused statistically significant increases in the composite through-plane and in-plane thermal conductivities. It is possible that thermally conductive pathways were formed that linked these carbon fillers, which resulted in increased composite thermal conductivity. Composites containing 70, 75, and 80 wt % synthetic graphite and the composite containing all three fillers (2.5 wt % carbon black, 65 wt % synthetic graphite, and 5 wt % carbon fiber) had in-plane thermal conductivities of 20 W m 21 K 21 or higher, which is desirable for bipolar plates.

Tensile and impact properties of carbon filled nylon‐6,6 based resins

Heiser

J of Applied Polymer Sci

Konell

et al. 2004

Self Cite

Electrically and thermally conductive resins can be produced by adding conductive fillers to insulating polymers. Mechanical properties such as tensile modulus, ultimate tensile stress, strain at ultimate tensile stress, and notched Izod impact strength are also important and cannot be ignored. This study focused on performing compounding runs, followed by injection molding and evaluation of tensile and impact properties of carbon filled nylon-6,6 based resins. The three carbon fillers investigated include an electrically conductive carbon black, synthetic graphite particles, and a surface treated polyacrylonitrile (PAN) based carbon fiber. Resins containing varying amounts of these single carbon fillers were produced and tested. In addition, combinations of fillers were investigated by conducting a full 2 3 factorial design and a complete replicate. The addition of carbon fiber increased the composite tensile modulus, ultimate tensile stress, and impact strength. Also, in many cases, combining two or three different fillers caused a statistically significant effect at a 95% confidence level. When comparing the results of this study with prior work, it appears that increased heteroatoms present on the carbon fiber surface likely improve composite ultimate tensile stress and impact strength.