Carbon Black Dispersion
Carbon black (graphite) is one of the most popular plastic additives not only because it is a cheap source of black pigment but also because it offers excellent mechanical properties and resistance to oxidation-weathering. However, in order for carbon black to be functional, it needs to be dispersed properly within the plastics. Large agglomerates of carbon black can cause the opposite of the desired results, especially in pipe materials. Therefore, assessing the degree of carbon black dispersion is important.
ISO 18553 method provides procedures for assessing the degree of dispersion by physical measurement of the size of the dispersed particles (carbon black or colour pigments) and arithmetically grading the particle size distribution. It also provides photographs for comparison with microscopic images of samples taken from raw-material compound or products in order to judge subjectively, the acceptability of carbon black or pigment dispersion.
