The present disclosure provides methods for producing an olefin polymer by contacting a C.sub.3-C.sub.40 olefin, ethylene and a diene with a catalyst system including an activator and a metallocene catalyst compound comprising a substituted or unsubstituted indacenyl group and obtaining a C.sub.3-C.sub.40 olefin-ethylene-diene terpolymer typically comprising from 1 to 35 mol % of ethylene, from 98.9 to 65 mol % C.sub.3-C.sub.40 olefin, and, optionally, from 0.1 to 10 mol % diene. Preferably, a propylene-ethylene-ethylidene norbornene is obtained.

A rubber composition based on at least an elastomer matrix, a carbon black, a silica, a silane coupling agent and short fibers, wherein the amount in phr of the silica is higher than that of the carbon black, wherein the amount of the silane coupling agent is more than 0.0% and less than 5.0% by weight per 100% by weight of the silica, wherein the amount of the short fibers is more than 0.0 phr and less than 5.0 phr and wherein the number-average length of the short fibers is less than 10 mm.

Elastomeric compositions are described that include at least one filler that are carbon nanostructures or fragments thereof. Methods to prepare elastomeric compositions are further described. Loadings of the carbon nanostructures can be from about 0.1 phr to about 50 phr or a volume fraction of from about 0.1 vol % to about 20 vol %.

The present invention is directed to a tire comprising a tread, two sidewalls, a carcass and at least two belts arranged radially between the carcass and the tread in a crown area of the tire. The tread has at least one axially outer edge portion covering the axially outermost edge of at least one of the belts and comprising a different rubber composition than a portion of the tread neighboring the axially outer edge portion of the tread. Furthermore, one of the sidewalls at least partially covers and contacts the axially outer surface of the axially outer edge portion of the tread.

A rubber composition according to an embodiment contains a rubber component and silica. In the rubber component, an amount of a vinyl bond unit derived from butadiene in a total amount of the rubber component is 10 mass % or more, and a content of a solution polymerized styrene-butadiene rubber is less than 50 mass %. A content of the silica is 90 parts by mass to 200 parts by mass, and a content of a metal oxide is less than 0.5 parts by mass, with respect to 100 parts by mass of the rubber component.

Compounds having an elastomer material, a filler material, at least one additive material, and at least one accelerant material are disclosed. In various embodiments, the filler material comprises a graphene-based carbon material. In various embodiments, the graphene-based carbon material comprises graphene comprising up to 15 layers, carbon aggregates having a median size from 1 to 50 microns, a surface area of the carbon aggregates at least 50 m.sup.2/g, when measured via a Brunauer-Emmett-Teller (BET) method with nitrogen as the adsorbate, and no seed particles.

The present disclosure provides methods for producing an olefin polymer by contacting a C.sub.3-C.sub.40 olefin, ethylene and a diene with a catalyst system including an activator and a metallocene catalyst compound comprising a substituted or unsubstituted indacenyl group and obtaining a C.sub.3-C.sub.40 olefin-ethylene-diene terpolymer typically comprising from 30 to 55 mol % ethylene, from 69.09 to 45 mol % C.sub.3 to C.sub.40 comonomer, and from 0.01 to 7 mol % diene wherein the Tg of the terpolymer is −28° C. or less. Preferably, a propylene-ethylene-ethylidene norbornene is obtained.

Provided is a tire having excellent rolling resistance and improved pass-by noise performance. The tire is a pneumatic tire comprising a side rubber provided on an outer side of a carcass in a tire width direction, in a sidewall portion, wherein a thickness of the side rubber in the tire width direction at a tire maximum width position is 1 mm or more, and a ratio 0° C. tan δ/30° C. tan δ of 0° C. tan δ to 30° C. tan δ of the side rubber is 2.00 or more, where the 0° C. tan δ is tan δ at 10 Hz and 0° C., and the 30° C. tan δ is tan δ at 10 Hz and 30° C.

A method for preparing a polymer, the method comprising polymerizing conjugated diene monomer in the presence of a lanthanide-based catalyst system including (i) a lanthanide-containing compound, (ii) triethyl aluminum, (iii) an aluminum hydride, and (iv) a halogen-containing compound; or a method for preparing a polymer, the method comprising polymerizing conjugated diene monomer in the presence of a lanthanide-based catalyst system including (i) a nickel-containing compound, (ii) triethyl aluminum, (iii) an aluminum hydride, and (iv) a halogen-containing compound selected from fluorine-containing compounds and chlorine-containing compounds.

A pneumatic tire includes: a rubber member A containing a rubber component containing 70 mass % to 100 mass % of a hydrogenated copolymer, sulfur, and a triazine-thiol compound; and a rubber member B containing sulfur and a rubber component containing a diene rubber. The hydrogenated copolymer is obtained by hydrogenating an aromatic vinyl-conjugated diene copolymer, has a weight average molecular weight of 300,000 or more as measured by gel permeation chromatography, and has a hydrogenation rate of a conjugated diene moiety of 80 mol % or more, the rubber member A and the rubber member B are in contact with each other at an interface, and a content of the triazine-thiol compound is 0.1 parts by mass to 5 parts by mass with respect to 100 parts by mass of the rubber component in the rubber member A.