Abstract: A rubber mixture is particularly based on natural rubber (NR), epoxidized natural rubber (E-NR), isoprene rubber (IR), butadiene rubber (BR), acrylate rubber (ACM), styrene-butadiene rubber (SBR), or blends of these types of rubber, particularly NR/SBR- blends or NR-BR- blends, as well as the usual mixing ingredients such as fillers, plasticizers, anti-aging media, as well as additional additives, if needed. This mixture produces a plate-like, elastic intermediate layer with low dynamic stiffening; high dynamic stressability; high specific volume resistivity; and low frequency-dependence of the dynamic stiffening. The intermediate layer is arranged particularly between the base of the rail and the top side of the tie in connection with high-speed rail tracks. The underside of the intermediate layer is provided with at least one recess, with formation of an edge extending all around, and facing the top side of the tie.

Abstract: The invention relates to a caoutchouc mixture for the manufacture of rubber products with low-temperature application capability, resistance to oil, low crystallization tendency, and high dynamic stressability, on the basis of natural caoutchouc, in particular viscosity-stabilized natural caoutchouc, and the usual mixture ingredients. The essence of said invention lies in that the caoutchouc mixture additionally contains 5 to 30% by weight 1,4-polybutadiene with a high cis-proportion, and 5 to 30% by weight epoxidized natural caoutchouc. An additional mixture variation is introduced.