Abstract: Methods for producing a cross-linkable rubber composition that comprises a masterbatch are disclosed. The masterbatch comprising a base masterbatch and the method includes forming the base masterbatch by adding a diene rubber to an internal mixer; adding a total quantity of a solid agglomerated material that includes carbon nanotubes into the mixing chamber; and mixing the diene elastomer and the solid agglomerated material. To ensure adequate distribution and dispersion of the material, the base masterbatch has a minimum Mooney viscosity ML(1+4)100 of at least 85 MU.

Abstract: A rubber composition based upon a cross-linkable rubber composition is provided that is in parts by weight per 100 parts by weight of rubber (phr), a diene rubber and a reinforcing filler that includes a reinforcing alumina filler with a nitrogen surface area of greater than 30 m2/g. The reinforcing alumina filler is at least 25 wt % of the reinforcing filler. An alumina covering agent is present and is either a benzilic acid derivative, a catechol derivative, or combinations thereof. The structure includes R1, R2, R3, and R4 that may be the same or different and are selected from a hydrogen, a C1 to C8 alkyl group, a C5 to C18 cycloalkyl group, or a C6 to C18 aryl group. A curing system is also present.

Abstract: Rubber compositions having a base masterbatch, the base masterbatch comprising a diene rubber and a solid agglomerated material comprising disaggregated carbon nanotubes consisting of a continuous network of carbon nanotubes, the continuous network comprising 1) voids and 2) aggregates of carbon nanotubes having a d50 mean size of less than 5 ?m, the voids and the aggregates together being in an amount that is less than 60% of a predetermined surface area, such percentage as determined by electron microscopy image analysis, the remainder being the disaggregated carbon nanotubes in the continuous network that do not comprise a clearly defined shape and being in an amount that is at least 40% of the predetermined surface area, wherein the base masterbatch has a minimum Mooney viscosity ML(1+4)100 of at least 85 MU; and a cure system.

Abstract: Methods for producing a cross-linkable rubber composition that comprises a masterbatch are disclosed. The masterbatch comprising a base masterbatch and the method includes forming the base masterbatch by adding a diene rubber to an internal mixer; adding a total quantity of a solid agglomerated material that includes carbon nanotubes into the mixing chamber; and mixing the diene elastomer and the solid agglomerated material. To ensure adequate distribution and dispersion of the material, the base masterbatch has a minimum Mooney viscosity ML(1+4)100 of at least 85 MU.