Formation of Latex Coagulum Composite

Abstract

A method of producing a coagulated latex composite. A coagulating mixture of a first elastomer latex and a particulate filler slurry is flowed along a conduit, and a second elastomer latex is introduced into the flow of the coagulating mixture.

What is claimed is:  
     
         1 - 14 . (canceled) 
     
     
         15 . An elastomer composite formed by the method of:
 flowing a coagulating mixture of a first elastomer latex and a particulate filler slurry along a conduit; and   introducing a second elastomer latex into the flow of the coagulating mixture.   
     
     
         16 . The elastomer composite of  claim 15 , wherein the method further comprises, before flowing the coagulating mixture, generating the coagulating mixture by feeding a continuous flow of the first elastomer latex to a mixing zone of a coagulum reactor defining an elongate coagulum zone extending from the mixing zone to a discharge end and comprising the conduit, and feeding a continuous flow of a fluid comprising particulate filler under pressure to the mixing zone of the coagulum reactor to form the coagulating mixture. 
     
     
         17 . The elastomer composite of  claim 16 , wherein the continuous flow of the fluid comprising particulate filler has a velocity from about 30 m/s to about 250 m/s, the continuous flow of the first elastomer latex has a velocity of at most about 10 m/s, and a residence time of the coagulating mixture in the coagulum reactor before introducing the second elastomer latex is from 1×10 ″2  s to about 6×10 ″2  s. 
     
     
         18 . The elastomer composite of  claim 15 , wherein the conduit comprises a first conduit portion having a first diameter, a second conduit portion having a second diameter greater than the first diameter, and a transition zone there between having a diameter that increases from the first diameter to the second diameter, wherein flowing comprises flowing the coagulating mixture into the second conduit portion from the first conduit portion, and introducing comprises introducing the second elastomer latex into the coagulating mixture in the transition region. 
     
     
         19 . The elastomer composite of  claim 18 , wherein flowing the coagulating mixture comprises flowing the coagulating mixture through the transition region under conditions of turbulent flow. 
     
     
         20 . The elastomer composite of  claim 15 , wherein the amount of the second elastomer in the composite is from about 0.5 wt % to about 50 wt %. 
     
     
         21 . The elastomer composite of  claim 15 , wherein the amount of the second elastomer in the composite is from about 16 wt % to about 38 wt %. 
     
     
         22 . The elastomer composite of  claim 15 , wherein the second elastomer is a synthetic elastomer. 
     
     
         23 . The elastomer composite of  claim 15 , wherein the second elastomer latex is natural rubber latex. 
     
     
         24 . The elastomer composite of  claim 23 , wherein the natural rubber latex comprises field latex, latex concentrate, skim latex, or a combination of two or more of these. 
     
     
         25 . The elastomer composite of  claim 23 , wherein a component of the natural rubber latex has been chemically or enzymatically modified. 
     
     
         26 . The elastomer composite of  claim 15 , wherein the particulate filler comprises a carbon black having a surface area of at least 95 m 2 /g as measured by STSA and a dibutyl phthalate adsorption of at least 80 mL/1OOg, and wherein the elastomer composite comprises at least 65 phr of the carbon black. 
     
     
         27 . The elastomer composite of  claim 15 , wherein the particulate filler comprises a carbon black having a surface area of at least 68 m 2 /g as measured by STSA and a dibutyl phthalate adsorption of at least 60 mL/1OOg, and wherein the elastomer composite comprises at least 70 phr of the carbon black. 
     
     
         28 . The elastomer composite of  claim 15 , wherein the particulate filler comprises a carbon black having a dibutyl phthalate adsorption of at least 60 mL/100 g, wherein the carbon black has a surface area and is present in the elastomer composite in an amount satisfying L>−0.26*S+94, where L is the amount of the carbon black in the elastomer composite in parts per hundred of rubber (phr) and S is the surface area in m 2 /g as measured by STSA. 
     
     
         29 - 44 . (canceled)