English Abstract
A Fractal Approach to the Mixing-Microstructure-Property Relationship on Rubber Compounds
Mamoru Hirata
Bridgestone.Inc, Tokyo,Japan
Nippon Gomu Kyokaishi,(2004),77(
2), 71-76 General Review in Japanese.

This research is concerned with exploration of the utility of fractal for characterizing the mixing treatment applied to a rubber compound and also for characterising the filler dispersion developed during mixing. Fractal is also used for characterization of the fracture surfaces generated during tensile testing of vulcanized samples. For these purposes, Maximum Entropy Method and Box Counting Method are applied to analyze the mixing treatment and the filler dispersion, respectively. These methods are effectively used and it is found that fractal dimensions of mixer-power-traces and fracture surfaces of vulcanized rubber decrease with the evolution of mixing time while the fractal dimension of the state-of-mix also decreases. The relationship of the fractal dimensions thus determined with conventional properties such as tensile strength, electrical resistance, and fracture surfaces are then explored.
Finally, the utility of the fractal methods for establishing mixing-microstructure-property relationships is compared with more conventional and well established methods such as electrical resistance and carbon black dispersion. It is found that the characterization by the fractal agrees with the conclusions from these conventional methods. In addition, it becomes possible to interpret the relationships between these conventional methods with the help of the fractal concept.

Fractal, Mixing, Carbon black dispersion, Maximum Entropy Method, Box counting Method