Influence of dispersing additives on the conductivity of carbon black pigment dispersion

Journal of Coatings Technology and Research (Impact Factor: 1.09). 8(5):553-561. DOI: 10.1007/s11998-011-9330-5

ABSTRACT The influence of dispersing additives on the electrical conductivity of carbon black pigments dispersed in an organic medium
was studied. Two dispersing additives were examined in combination with two different carbon blacks, a conductive carbon black
and a nonconductive one. These carbon blacks differ in the size of their aggregates and in the amounts of surface oxygen groups.
Both of the additives form a monolayer when adsorbed on either of the pigment surfaces. FTIR studies showed that chemical
bonding of one of the additives on the surfaces of both pigments had occurred. Conductivity decreases with increasing additive
concentration, but in the case of the chemically bonded additive, the conductivity of the dispersion remained high even at
higher additive loadings. This study helps in understanding the effects such additives have on the specific conductivity of
composite materials that contain dispersed carbon black pigment particles.

KeywordsCarbon black–Dispersion–Adsorption–Conductivity

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May 31, 2014