Effects of γ-Radiation Treatment on the Reinforcing Properties of Carbon Black in Rubber Compound

Abstract

Commercial graphite flakes and carbon black grade N234 have been subjected to γ-radiation treatment to a total dose of IMGy. The resulting radiation-damaged materials were studied by Raman spectroscopy. Raman spectra have revealed that graphite underwent substantial changes in its structure with formation of hexagonal diamond sites as well as onion-like and amorphous carbon domains. Changes also in the Raman spectra of irradiated carbon black have been observed which could be interpreted in the light of the results on irradiated graphite. A compound evaluation of γ-treated carbon black has been performed in comparison to a pristine sample. The results show a spectacular increase in the reinforcing effect as measured by the 200% and 300% modulus, hence an increase of the filler-to-polymer interaction, a reduction of the Payne effect and of the hysteresis (measured by tand at 70[ddot]C).