Silica reinforced rubber composition and tire with tread thereof

Claim 2

A rubber composition comprised of (A) 100 parts by weight of at least one diene-based elastomer, (B) about 25 to about 100 phr of filler composed of particulate, precipitated silica and carbon black, and (C) a silica coupler selected from (i) poly-(2-propanol-1,3-polysulfide), having from 2 to 6 sulfur atoms in its polysulfide bridge, or from (ii) a combination of about 95 to about 25 weight percent of said poly-(2-propanol-1,3-polysulfide) and, correspondingly, about 5 to about 75 weight percent of bis-(3-trialkoxysilylalkyl) polysulfide containing from 2 to 8 sulfur atoms in its polysulfide bridge; wherein the weight ratio of said silica coupler to silica is in a range of about 0.01/1 to about 0.2/1; wherein the weight ratio of silica to carbon black, is at least about 0.1/1.

Claim 3

The rubber composition of claim 1 where said poly- (2-propanol-1,3-polysulfide) is on a carbon black carrier.

Claim 4

The rubber composition of claim 1 wherein the said silica coupler consists essentially of poly(2-propanol-1,3-polysulfide); and wherein the weight ratio of said silica coupler to silica is in a range of about 0.01/1 to about 0.2/1.

Claim 5

The rubber composition of claim 1 wherein the said silica coupler is a combination of about 95 to about 25 weight percent poly-(2-propanol-1,3-polysulfide) and, correspondingly, about 5 to about 75 weight percent of bis-(3-triethoxysilylpropyl) tetrasulfide and bis-(3-triethoxysilylpropyl) trisulfide.

Claim 6

The rubber composition of claim 1 wherein the diene based elastomer is selected from at least one of cis 1,4-polyisoprene rubber, 3,4-polyisoprene rubber, styrene/butadiene copolymer rubbers, isoprene/butadiene rubber, styrene/isoprene/butadiene terpolymer rubbers, cis 1,4-polybutadiene rubber, medium vinyl polybutadiene rubber, high vinyl polybutadiene rubber and emulsion polymerization prepared styrene/butadiene/acrylonitrile terpolymer rubber and butadiene/acrylonitrile copolymer rubber.

Claim 7

The rubber composition of claim 1 wherein the silica is characterized by having a BET surface area in a range of about 50 to about 300 square meters per gram and a dibutylphthalate (DBP) absorption value in a range of about 150 to about 300.

Claim 8

The rubber composition of claim 2 wherein the silica is characterized by having a BET surface area in a range of about 50 to about 300 square meters per gram and a dibutylphthalate (DBP) absorption value in a range of about 150 to about 300.

Claim 9

The rubber composition of claim 3 wherein the silica is characterized by having a BET surface area in a range of about 50 to about 300 square meters per gram and a dibutylphthalate (DBP) absorption value in a range of about 150 to about 300.

Claim 10

A rubber composition comprised of (A) 100 parts by weight of at least one diene-based elastomer, (B) about 25 to about 90 phr particulate silica, (C) up to about 30 phr carbon black, and (D) a silica coupler which is collectively composed of about 90 to about 55 weight percent poly-(2-propanol-1,3-polysulfide), about 10 to about 45 weight percent of bis-(3-triethoxysilylpropyl)tetrasulfide and bis-(3triethoxysilylpropyl)trisulfide; wherein the weight ratio of said silica coupler to silica is in a range of about 0.01/1 to about 0.2/1; wherein the weight ratio of silica to carbon black is in a range of about 3/1 to about 30/1; wherein the silica is characterized by having a BET surface area in a range of about 50 to about 300 square meters per gram and a dibutylphthalate (DBP) absorption value in a range of about 150 to about 300.

Claim 11

A rubber composition comprised of (A) 100 parts by weight of at least one diene-based elastomer, (B) about 25 to about 90 phr particulate silica, (C) up to about 30 phr carbon black, and (D) a silica coupler which is collectively composed of about 90 to about 55 weight percent poly-(2-propanol-1,3-polysulfide), about 10 to about 45 weight percent of bis-(3-triethoxysilylpropyl)tetrasulfide and bis-(3triethoxysilylpropyl)trisulfide; wherein the weight ratio of said silica coupler to silica is in a range of about 0.01/1 to about 0.2/1; wherein the weight ratio of silica to carbon black is in a range of about 3/1 to about 30/1; wherein the silica is characterized by having a BET surface area in a range of about 50 to about 300 square meters per gram and a dibutylphthalate (DBP) absorption value in a range of about 150 to about 300.

Claim 12

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 1.

Claim 13

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 2.

Claim 14

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 3.

Claim 15

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 4.

Claim 16

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 5.

Claim 17

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 6.

Claim 18

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 7.

Claim 19

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 8.

Claim 20

A tire having a rubber tread wherein said tread is comprised of the rubber composition of claim 9.