Morphological investigations on carbon black particles by atomic force microscopy

Abstract The atomic force microscope (AFM) can profile surfaces similar to the scanning tunneling microscope (STM) at resolutions down to the atomic level. To investigate carbon-black particles and subsequently styrene-butadiene-rubber, filled with carbon black, a STM was modified to run as an AFM. An optical detection system is used to measure the deflection of the cantilever. Atomic resolution was achieved by forces in the order of 5·10−8 N on mica with the AFM. Structural investigations of carbon-black particles of different dimensions with the AFM agree with the data of the manufacturer. The model of the microstructure of such particles, built up of 1–3 nm large, tilted domains of graphite structures, could be confirmed. This surface roughness is probably an important parameter for the strengthening mechanism of carbon black in elastomers.</jats:p