Polarized infrared transmittance of carbon black‐polyvinylchloride composite

Resistivity measurement on carbon black‐polyvinylchloride (PVC) composites combined with Monte Carlo calculations on the percolation threshold of a two‐dimensional system of oriented sticks has suggested that the carbon black aggregates in these compression molded composites are oriented. Although electron microscopy failed to disclose structure in the composite, polarized infrared transmittance measurements do provide direct evidence for the orientation of carbon black aggregates. The degree of orientation from optical polarization correlates with orientation suggested by the resistivity measurements.