Abstract
Dispersion, morphology and electrical conductivity of Ketjenblack (KB) filled High Density Polyethylene (HDPE)/Isotactic Polypropylene (iPP) blends have been studied. The percolation threshold of KB filled HDPE50/iPP50 blends, 0.75 phr KB content, is much lower than those of the individual polymers. The SEM micrographs verified that the enhancement of conductivity could be attributed to the selective location of KB in the HDPE phase. A double percolation is the basic requirement for the conductivity of the composites, i.e. The percolation of KB in the HDPE phase and the continuity of this phase in the blends, which are defined as the first percolation and the second percolation, respectively. The SEM micrographs also showed that KB could affect the morphology of the blends. At higher KB content, the HDPE domains are elongated from spherical into strip shape, which can easily form a continuous structure. As a result, the second percolation threshold of the blends filled with 2.0 phr KB, 30 wt% HDPE, is lower than that of the blends filled with 1 phr KB, 40 wt% HDPE. The molding temperature and time have a strong influence on the first percolation. With decreasing molding temperature and time, the first percolation threshold is shifted to higher KB content, but there is little influence of molding temperature and time on the second percolation threshold.
| Original language | English |
|---|---|
| Pages (from-to) | 227-236 |
| Number of pages | 10 |
| Journal | Composite Interfaces |
| Volume | 6 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1998 |
| Externally published | Yes |
Keywords
- Blends
- Double percolation
- Electrical conductivity
- High Density Polyethylene
- Isotactic Polypropylene
- Ketjenblack
- Selective location of the filler
ASJC Scopus subject areas
- Ceramics and Composites
- General Physics and Astronomy
- Surfaces, Coatings and Films