RUBBER COMPOSITION WITH LOW SURFACE AREA CARBON BLACK
Tire components including bead area components and sidewall supports for a run-flat pneumatic tire that are constructed of a material based upon a cross-linkable rubber composition. The cross-linkable rubber composition includes, per 100 parts by weight of rubber (phr)* between 10 phr—and 90 phr—of a polyisoprene rubber and between 10 phr—and 90 phr of a polybutadiene rubber. The rubber composition further includes between 60 phr and 100 phr of a thermal carbon black having a nitrogen surface area of between 5 m 2 /g and 15 m 2 /g and a DBP absorption of between 30 cm 3 /100 g and 55 cm 3 /100 g. The rubber composition is cured with a sulfur curing system.
1 . A run-flat tire comprising a sidewall support member, the sidewall support member being constructed of a material that is based upon a cross-linkable rubber composition, the cross-linkable rubber composition comprising, per 100 parts by weight of rubber (phr):
between 10 phr and 90 phr of a polyisoprene rubber;
between 10 phr and 90 phr of a polybutadiene rubber;
between 60 phr and 100 phr of a thermal carbon black having a nitrogen surface area of between 5 m 2 /g and 15 m 2 /g and a DBP absorption of between 30 cm 3 /100 g and 55 cm 3 /100 g; and
a sulfur cure system.
2 . The run-flat tire of claim 1 , wherein the rubber composition comprises between 65 phr and 85 phr of the carbon black.
3 . The run-flat tire of claim 1 , wherein the polyisoprene rubber is selected from a natural rubber, a synthetic polyisoprene rubber or combinations thereof.
4 . The run-flat tire of claim 1 , wherein the rubber composition comprises between 20 phr and 40 phr of natural rubber and between 60 phr and 80 phr of polybutadiene rubber.
5 . The run-flat tire of claim 1 , wherein the rubber composition comprises between 70 phr and 90 phr of natural rubber and between 10 phr and 30 phr of polybutadiene rubber.
6 . The run-flat tire of claim 1 , wherein the nitrogen surface area of the thermal carbon black is between 7 m 2 /g and 12 m 2 /g.
7 . The run-flat tire of claim 1 , wherein the DBP absorption of the thermal carbon black is between 35 cm 3 /100 g and 50 cm 3 /100 g.
8 . The run-flat tire of claim 1 , wherein the mean particle diameter of the thermal carbon black is between 180 nm and 450 nm.
9 . The run-flat tire of claim 1 , wherein the mean particle diameter of the thermal carbon black is between 250 nm and 350 nm.
10 . A pneumatic tire comprising a plurality of bead area components, one or more of the plurality of bead area components being selected from a bead apex or a toe guard, the one or more selected bead area components being constructed of a material that is based upon a cross-linkable rubber composition, the cross-linkable rubber composition comprising, per 100 parts by weight of rubber (phr):
between 10 phr and 90 phr of a polyisoprene rubber;
between 10 phr and 90 phr of a polybutadiene rubber;
between 60 phr and 100 phr of a thermal carbon black having a nitrogen surface area of between 5 m 2 /g and 15 m 2 /g and a DBP absorption of between 30 cm 3 /100 g and 55 cm 3 /100 g; and
a sulfur cure system.