Low rolling resistance tire tread

Claim 1

Heat-vulcanizable tread strips for the production of pneumatic tire treads for motor vehicles, obtained from vulcanizable compositions consisting essentially of: an amorphous elastomer component which exhibits a Mooney viscosity of 30-130; 40-60% by weight of active, reinforcing filler which comprises one or more tread carbon blacks or a mixture of 80-95% by weight of one or several tread carbon blacks and 5-20% by weight of one or several active silicic acids treated with silane adhesion promoters; 0-20% by weight of plasticizer oil which comprises conventional aromatic, aliphatic and naphthenic hydrocarbons, based on the elastomer component, and an effective amount of a vulcanizing agent, wherein a. the elastomer component consists essentially of a mixture of blend components, said mixture of blend components consisting essentially of in percent by weight based on the total mixture, a.1.1 20-40% by weight of a polyisoprene I, a.1.2 20-80% by weight of a polybutadiene I, wherein the polyisoprene I and the polybutadiene I are present as a mixture of homopolymers or as blocks in a block copolymer, a.2.1 0-30% by weight of a polybutadiene II, a.2.2 0-50% by weight of an elastomer selected from the group consisting of 1,4-cis-IR and NR (polyisoprene II), and a.2.3 0-60% by weight of SBR with 10-25% by weight recurring units, obtained by polymerization of styrene, excluding styrene blocks; b. the elastomer component has a defo elasticity of 12-45 and a nonuniformity (U =Mw/Mn-1) of 0.8-5.5; c.1 the polyisoprene I, the polybutadiene I, and the block copolymer have been obtained by polymerization in an inert, organic solvent in the presence of an organolithium catalyst and a Lewis base from the group of the ethers, tertiary amines, and their mixtures as the cocatalyst; c.2 the polyisoprene I and the corresponding block in the block copolymer consist essentially of 55-85% by weight of recurring units obtained by 1,2- and 3,4-polymerization, and 15-45% by weight of recurring units obtained by 1,4-polymerization of isoprene; c.3 the polybutadiene I and the corresponding block in the block copolymer consist essentially of 40-70% by weight of recurring units obtained by 1,2-polymerization, and 30-60% by weight of recurring units obtained by 1,4-polymerization of 1,3-butadiene, c.4 the polybutadiene II is obtained by Ziegler polymerization; it consists essentially of ≦10% by weight of recurring units obtained by 1,2-polymerization and ≧90% by weight of recurring units obtained by 1,4-polymerization of 1,3-butadiene.