Theoretical model of the mechanical properties of elastomer network with thermoreversible junctions have been obtained on the basis of nonequilibrium thermodynamics and physical kinetics methods. Non-Gaussian assumption for a free energy of chains in the equilibrium state have been used As was established, the possibility of construction of the tearing master-curve is determined by the energy of junctions. If the energy of junctions is less then 60 kJ/mol the time-temperature superposition principle contravenes and anomalous large fracture work is observed. II was found that ultimate tensile strength versus junctions energy curve has a maximum. Thus, an optimal value of junctions energy exists.