Methods of making an elastomer composite reinforced with silica and products containing same

Abstract

Methods to make a silica elastomer composite with a destabilized dispersion of silica are described, along with silica elastomer composites made from the methods. The advantages achieved with the methods are further described.

1 . A method of producing a silica elastomer composite, comprising:
 (a) providing a continuous flow under pressure of at least a first fluid comprising a destabilized dispersion of silica and a continuous flow of at least a second fluid comprising elastomer latex;   (b) providing volumetric flow of the first fluid relative to that of the second fluid to yield a silica content of about 15 phr to about 180 phr in the silica elastomer composite;   (c) combining the first fluid flow and the second fluid flow with a sufficiently energetic impact to distribute the silica within the elastomer latex to obtain a flow of a solid silica-containing continuous rubber phase or semi-solid silica-containing continuous rubber phase, wherein said flow of said solid silica-containing continuous rubber phase or semi-solid silica-containing continuous rubber phase forms in two seconds or less after said combining of said first fluid flow and said second fluid flow; and   (d) recovering said solid or semi-solid silica-containing continuous rubber phase that is the silica elastomer composite.   
     
     
         2 . (canceled) 
     
     
         3 . The method of  claim 1 , wherein said flow of said solid or semi-solid silica-containing continuous rubber phase forms in about 50 milliseconds to about 1500 milliseconds after combining said first fluid flow and second fluid flow. 
     
     
         4 - 8 . (canceled) 
     
     
         9 . The method of  claim 1 , wherein the volumetric flow of said first fluid and of said second fluid are at a volumetric flow ratio of first fluid to second fluid of from 0.2:1 to 2.8:1. 
     
     
         10 . The method of  claim 1 , wherein the volumetric flow of said first fluid and of said second fluid are at a volumetric flow ratio of first fluid to second fluid of from 0.4:1 to 3.2:1, and said destabilized dispersion of silica includes at least one salt. 
     
     
         11 . The method of  claim 1 , wherein the volumetric flow of said first fluid and of said second fluid are at a volumetric flow ratio of first fluid to second fluid of from 0.2:1 to 2.8:1, and said destabilized dispersion of silica includes at least one acid. 
     
     
         12 . (canceled) 
     
     
         13 . The method of  claim 1 , wherein said destabilized dispersion of silica comprises at least one acid, and wherein said elastomer latex present in said second fluid has an ammonia concentration of from about 0.3 wt % to about 0.7 wt % based on the weight of the elastomer latex, and a molar ratio of hydrogen ions in said acid in said first fluid to ammonia in said second fluid is at least 1:1. 
     
     
         14 . The method of  claim 1 , wherein said silica content of said silica elastomer composite is from about 35 phr to about 115 phr. 
     
     
         15 - 16 . (canceled) 
     
     
         17 . The method of  claim 1 , wherein said destabilized dispersion of silica comprises about 10 wt % to about 28 wt % silica. 
     
     
         18 - 27 . (canceled) 
     
     
         28 . The method of  claim 1 , wherein said first fluid comprises an aqueous fluid. 
     
     
         29 . (canceled) 
     
     
         30 . The method of  claim 1 , wherein said first fluid comprises an aqueous fluid, further comprising at least one salt, and at least one acid. 
     
     
         31 - 41 . (canceled) 
     
     
         42 . The method of  claim 1 , wherein said silica has a BET surface area of from about 20 m 2 /g to about 450 m 2 /g. 
     
     
         43 . The method of  claim 1 , wherein said elastomer latex is natural rubber latex. 
     
     
         44 . (canceled) 
     
     
         45 . The method of  claim 43 , wherein the natural rubber latex is in the form of an epoxidized natural rubber latex. 
     
     
         46 . The method of  claim 43 , wherein the natural rubber latex is in the form of a latex concentrate. 
     
     
         47 - 54 . (canceled) 
     
     
         55 . The method of  claim 1 , further comprising bringing the flow of solid or semi-solid silica-containing continuous rubber phase into contact with at least one destabilizing agent. 
     
     
         56 - 58 . (canceled) 
     
     
         59 . The method of  claim 1 , wherein said second fluid comprises a blend of two or more different elastomer latices. 
     
     
         60 . The method of  claim 1 , further comprising providing one or more additional fluids and combining the one or more additional fluids with said first fluid flow and second fluid flow, wherein said one or more additional fluids comprise one or more elastomer latex fluids, and said additional fluids are the same as or different from said elastomer latex present in said second fluid flow. 
     
     
         61 - 62 . (canceled)