Rubber composition

A rubber composition formed according to an improved rubber compounding process, wherein the improvement comprises vulcanizing natural rubber, polybutadiene rubber, polyisoprene rubber, or styrene-butadiene rubber containing a substantially uniform dispersion of:

• A. 1. particulate Agent E at a level of from about 5 to about 200 phr,
• 2. Agent F at a level of from about 0.005 to about 15 phr, and
• 3. Agent G at a level of from about 0.005 to about 15 phr;
• or
• B. 1. a particulate adduct of Agents E and F having a median particle size in the range of from about 0.01 to about 20 microns and present at a level such that the portion thereof contributed from Agent E is at a level of from about 5 to about 200 phr and the portion thereof contributed from Agent F is at a level of from about 0.005 to about 15 phr, and
• 2. Agent G at a level of from about 0.005 to about 15 phr;
• or
• C. 1. a particulate adduct of Agents E and G having a median particle size in the range of from about 0.01 to about 20 microns and present at a level such that the portion thereof contributed from Agent E is at a level of from about 5 to about 200 phr and the portion thereof contributed from Agent G is at a level of from about 0.005 to about 15 phr, and
• 2. Agent F at a level of from about 0.005 to about 15 phr;
• or
• D. a particulate adduct of Agents E, F, and G having a median particle size in the range of from about 0.01 to about 20 and present at a level such that the portion thereof contributed from Agent E is at a level of from about 5 to about 200 phr, the portion thereof contributed from Agent F is at a level of from about 0.005 to about 15 phr and the portion thereof contributed from Agent G is at a level of from about 0.005 to about 15 phr;
• wherein Agent E comprises phyllosilicate mineral particles having a median particle size in the range of from about 0.01 to about 20 microns;
• wherein Agent F comprises an organosilane of formula I ##STR3## wherein X is a group which is, or which upon hydrolysis forms a group which is, capable of reacting with a reactive site on the phyllosilicate mineral particles so as to form a bond between the organosilane of formula I and the phyllosilicate mineral particles,
• wherein Y is an alkyl, aryl or alkyl-substituted aryl group containing from 1 to 20 carbon atoms and bears a functional group capable of reacting with a reactive site on the rubber so as to form a bond between the organosilane of formula I and the rubber, and
• wherein R.sub.1 and R.sub.2 are the same or different and are each selected from the group consisting of the groups described by X and Y, an alkyl group containing from 1 to 20 carbon atoms, an aryl group, and an alkyl-substituted aryl group wherein the alkyl substituents contain a total of from 1 to 20 carbon atoms;
• and
• wherein Agent G comprises an amine of formula II ##STR4## wherein Z is zero or a positive integer from 1 to 12, wherein R.sub.3, R.sub.4, R.sub.6 and R.sub.7 are the same or different and are each selected from the group consisting of hydrogen, an alkyl group containing from 1 to 20 carbon atoms, an aryl group and an alkyl-substituted aryl group wherein the alkyl substituents contain a total of from 1 to 20 carbon atoms,
• wherein R.sub.5 is an alkylene group containing from 2 to 16 carbon atoms,
• wherein, when Z is zero, at least one of R.sub.3, R.sub.4 and R.sub.7 bears a first functional group which is selected from the group consisting of a mercapto group, allyl group, vinyl group, epoxy group, methacryloxy group, acryloxy group, hydroxy group, and a group hydrolyzable to a hydroxy group, and at least one of R.sub.3, R.sub.4 and R.sub.7 bears a second functional group which is, or which upon hydrolysis forms a group which is selected from the group consisting of a hydroxy group, an alkoxy group, a mercapto group, and a sulfide group and which second functional group is located at a carbon atom which is beta or gamma to the nearest tertiary nitrogen atom in formula II, and
• wherein, when Z is not zero, at least one of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 bears a first functional group which is selected from the group consisting of a mercapto group, allyl group, vinyl group, epoxy group, methacryloxy group, acryloxy group, hydroxy group, a group hydrolyzable to a hydroxy group, and, in addition, when R.sub.5 contains more than 3 carbon atoms, at least one of R.sub.3, R.sub.4, R.sub.6 and R.sub.7 bears a second functional group which is, or which upon hydrolysis forms a group which is, selected from the group consisting of a hydroxy group, an alkoxy group, a mercapto group, and a sulfide group and which second functional group is attached to a carbon atom which is beta or gamma to the nearest tertiary nitrogen atom in formula II.