The sustainability of sealing products and structures made from silicone rubber can be determined in several ways, with simulations in the virtual reality offering numerous advantages related to economic, time, and energy efficiency. However, predicting such behavior requires information about the time-dependent behavior of the material, which was the primary objective of the presented research. Within the scope of activities, it was necessary to define the thermal stability of the material, the stress limit of linear viscoelasticity (LVO), and, finally, the required material function. The mentioned analyses were conducted using a differential dynamic calorimeter and a modular rotational rheometer in shear loading mode. We found that silicone rubber has a glass transition temperature at T$_g$ = -60°C and that the process of additional crosslinking begins above a temperature of 150°C. Tests to determine the shear material function J(t) were carried out within the LVO range, i.e., under τ$_{LVE}$ = 0.0172 MPa, using time-temperature superposition (t-Ts). It was shown that the given temperature range, i.e., from 25°C to 150°C, enables the time-dependent characterization of the material function J(t) through six decades, where the change in the function's value is remarkably small, from 0.66 1/MPa to 0.83 1/MPa (equivalent to a modulus change from 1.5 MPa to 1.2 MPa).
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