Abstract
In this paper, we investigated transitions of physical properties, dispersion level of carbon black, volume of bound rubber, dependence of dynamic modulus on amplitude, amount of plastic elements, spin-spin relaxation time, dependence of loss factor on temperature, for carbon black filled SBR in process of mixing.
We pointed out that mixing process consisted of two homogenizing dispersion steps of carbon black, the first one was of macroscopic and the second one was of microscopic. In the first step there were destruction of aggregated carbon black, followed by dipersion of carbon black, and restriction on rubber molecule chains due to reactions with carbon black surface. In addition, there was breakdown of plastic elements within aggregated carbon black. In the second step, there were destruction of rubber molecule-rubber molecule interaction due to stabilization of the microscopic heterogeneous structure of carbon black filled rubber and increment of entropy of rubber molecule chains.
Consequently, we confirmed that mixing affected the first step differently from the second step with respect to modulus, plasticity, mobility of molecular chanis and temperature dependency of dynamic properties.
