Novel processing aids for natural and synthetic rubber compounds

Abstract

This invention is directed to novel compositions which aid in the processing of natural and synthetic rubber by permitting the usual peptizing step of such processing to be omitted. These compositions contain salts of aromatic sulfonic acids as well as long chain (fatty) acids as essential ingredients.

What is claimed is: .[.1. A composition of matter comprising: 
     
        sulfonic acid is from 1:1 to 8.33:1..]. .[.2.  A composition according to claim 1 wherein the long chain fatty organic acid is stearic acid..]. .[.3. A composition according to claim 1 wherein the alkyl substituents have between 8 and 12 carbons in the chain..]. .[.4. A composition according to claim 1 wherein the alkali salt of the aromatic sulfonic acid is selected from the group consisting of potassium octylbenzene sulfonate, 
     
     
        potassium n-dodecylbenzene sulfonate and mixtures thereof..]. 5. A composition .[.according to claim 1 to which is added.]. .Iadd.of matter comprising: a. an alkali salt of an aromatic sulfonic acid having the formula ##STR3##  wherein x is hydrogen or a branched or straight chain alkyl group having from 4 to 14 carbon atoms;   b. a long chain fatty organic acid having a maximum of about 22 carbon atoms in the chain wherein the weight ratio of said fatty acid to said sulfonic acid is from 1:1 to 8.33:1; and   c. .Iaddend. additional materials including aromatic esters, compounds with alcoholic and glycolic hydroxyl groups, potassium or sodium soaps of fats or fatty acids, a fatty acid, a metal soap of zinc, magnesium, calcium or   
     
     
        barium, and a paraffin. 6. A composition according to claim 5 comprising from about 3 percent to about 15 percent of the alkali salt of said aromatic sulfonic acid, about 5 percent to about 25 percent of said long chain fatty organic acid, about 7 percent to about 15 percent diphenylphthalate, about 10 percent to about 20 percent tetraethylene glycol mono-nonylphenolether, about 5 percent to about 10 percent tripropylene glycol, about 5 percent to about 20 percent potassium stearate, about 4 percent to about 10 percent zinc oleate, up to 5 percent 
     
     
        cetyl alcohol, and about 15 percent to about 20 percent petrolatum. 7. An improved rubber composition comprising a rubber base, carbon black, rubber additives wherein the improvement comprises a small but effective amount of a composition comprising: a. the alkali salt of an aromatic sulfonic acid having the formula ##STR4##  wherein x is hydrogen or a branched or straight chain alkyl group having from 4 to 14 carbon atoms, and   b. a long chain fatty organic acid having a maximum of about 22 carbon atoms in the chain, wherein the weight ratio of said fatty acid to said sulfonic acid is from 1:1 to 8.33:1, and said amount being sufficient to eliminate the need for .[.subse-quent.]. .Iadd.subsequent   
     
     
        .Iaddend.separate mastication of said rubber composition. 8. A rubber composition according to claim 7 wherein said amount is between about 1 
     
     
        percent to about 5 percent by weight. 9. An improved method for compounding rubber comprising admixing rubber with an additive of the class consisting of pigments, fillers and vulcanizing agents, wherein the improvement comprises admixing a composition .[.according to claim 1.]. .Iadd.comprising: a. an alkali salt of an aromatic sulfonic acid having the formula ##STR5##  wherein x is hydrogen or a branched or straight chain alkyl group having from 4 to 14 carbon atoms; and   b. a long chain fatty organic acid having a maximum of about 22 carbon atoms in the chain wherein the weight ratio of said fatty acid to said sulfonic acid is from 1:1 to 8.33:1 .Iaddend. with rubber at the beginning of the mixing cycle prior to mastication of the rubber and no later than the time when said rubber is admixed with     
     
     
        said additive. 10. A method according to claim 9 wherein said composition comprises from about 3 percent to about 15 percent of the alkali salt of said aromatic sulfonic acid, about 5 percent to about 25 percent of said long chain .[.(fatty).]. .Iadd.fatty .Iaddend.organic acid, about 7 percent to about 15 percent diphenylphthalate, about 10 percent to about 20 percent tetraethylene glycol mono-nonylphenolether, about 5 percent to about 10 percent tripropylene glycol, about 5 percent to about 20 percent potassium stearate, about 4 percent to about 10 percent zinc oleate, up to 5 percent cetyl alcohol, and about 15 percent to about 20 percent petrolatum.