Abstract
In the oxidative degradation of a plenty of rubber vulcanizates at high temperature, their stress decays are principally caused by the random scission along the main chain.
Equation (I) is obtained for such rubber vulcanizates with impurities, because a stationary oxidative reaction occurs owing to such impurities._??_(I)
The chemical relaxation in eq.(I) follows the well-known Maxwellian decay curve which is shown by eq.(II)._??_(II)
On the other hand, a modified equation (III) instead of eq.(I) is available for rubber vulcanizates with less impurities of refined vulcanizates because of unstationary oxidation._??_(III)
The chemical relaxation in eq.(III) shows the Modified Maxwellian decay curve shown by eq.(IV)._??_(IV)
