EFFECTS OF OZONE OXIDATION ON CARBON-BLACK SURFACES

Surface effects of ozone treatment with a fluidized bed-type reactor o n carbon black have been studied. It has been observed that the surfac e oxygen level is proportional to the total volume of ozone supplied p er unit area of carbon black surface. The ozone treatment increases th e acidity of the carbon black surface. A limiting pH value has been ob tained at a surface oxygen concentration of around 6 at %. The surface oxygen introduced on the carbon black is most likely present as carbo xylic acid groups as indicated by both high-resolution X-ray photoelec tron spectroscopy and Fourier transform-infrared spectroscopy results. The ozone treatment of a carbon black decreases the tensile strength for a natural rubber (non-polar), but increases the tensile strength f or a nitrile butadiene rubber (polar).