Carbon black compositions

Abstract

Suggested is a carbon black composition showing a narrow Aggregate Size Distribution (ASD) characterized by a ΔD 50 /D mode value of about 0.58 to about 0.65 and a Relative Span (D 90 -D 10 )/D 50 of about 0.5 to about 0.8, which is obtainable by means of a modified furnace reactor. The composition shows superior additive performance and allows producing e.g. bus or truck tires with improved wear resistance and reinforcement.

1 . A furnace reactor comprising the following elements:
 (i) a combustion chamber;   (ii) a cylindrical tube for injection of the feedstock;   (iii) a Venturi shaped reaction tunnel for carbon black formation and   (iv) a cylindrical tunnel to terminate carbon black formation by a quench,   wherein   (a) the combustion chamber narrows conically over its length l from a diameter d 1  to a diameter d 2 ,   (b) the tube shows over its length l 2  a constant diameter d 2 ,   (c) the reaction tunnel expands over its length l 3  from diameter d 2  to diameter d 3 , and   (d) the cylindrical tunnel shows over its length l 4  a constant diameter d 3 ,   on condition that the ratio d 2 :l 2  ranges from about 1:2 to about 1:6.   
     
     
         2 . A carbon black composition showing a ΔD 50 /D mode  of 0.58 to 0.65 and a Relative Span (D 90 -D 10 )/D 50  of about 0.5 to about 0.8. 
     
     
         3 . The composition of  claim 2 , showing in addition a Quartile Ratio (QR) D 75 /D 25  of about 1.2 to about 1.5. 
     
     
         4 . The composition of  claim 2 , showing in addition a Polydispersity Index of less than about 1.35. 
     
     
         5 . The composition of  claim 2 , showing STSA value of about 90 to about 180 m 2 /g. 
     
     
         6 . The carbon black composition of  claim 2 , obtained by the steps of
 (A) subjecting a hydrocarbon starting material to a high temperature combustion gas stream in order to achieve thermal decomposition,   (B) cooling the reaction gases, and   (C) recovering the carbon black thus obtained,   wherein the reaction is conducted in a furnace reactor comprising the following elements:   (i) a combustion chamber;   (ii) a cylindrical tube for injection of the feedstock;   (iii) a Venturi shaped reaction tunnel for carbon black formation and   (iv) a cylindrical tunnel to terminate carbon black formation by a quench, wherein   (a) the combustion chamber narrows conically over its length h from a diameter d 1  to a diameter d 2 ,   (b) the tube shows over its length l 2  a constant diameter d 2 ,   (c) the reaction tunnel expands over its length l 3  from diameter d 2  to diameter d 3 , and   (d) the cylindrical termination tunnel shows over its length l 4  a constant diameter d 3 ,   on condition the ratio d 2 :l 2  ranges from about 1:2 to about 1:6.   
     
     
         7 . A process for obtaining a carbon black composition showing a ΔD 50 /D more  ratio of 0.58 to 0.65 and a Relative Span of about 0.5 to about 0.8, comprising the following steps:
 (A) subjecting a hydrocarbon starting material into a high temperature combustion gas stream in order to achieve thermal decomposition, 
 (B) cooling the reaction gases 
 (C) recovering of the carbon black thus obtained, 
 wherein the reaction is conducted in a furnace reactor comprising the following elements: 
 (i) a combustion chamber; 
 (ii) a cylindrical tube for injection of the feedstock; 
 (iii) a Venturi shaped reaction tunnel for carbon black formation; and 
 (iv) a cylindrical tunnel to terminate carbon black formation by a quench, wherein 
 (a) the combustion chamber narrows conically over its length l from a diameter d 1  to a diameter d 2 , 
 (b) the tube shows over its length l 2  a constant diameter d 2 , 
 (c) the reaction tunnel expands over its length l 3  from diameter d 2  to diameter d 3 , and 
 (d) the cylindrical termination tunnel shows over its length l 4  a constant diameter d 3 , 
 on condition the ratio d 2 :l 2  ranges from about 1:2 to about 1:6. 
 
     
     
         8 . A method for improving the properties of a polymer composition comprising the step of by adding the carbon black composition of  claim 2  to the polymer composition. 
     
     
         9 . A method for improving wear resistance and reinforcement of a polymer composition, comprising the step of adding the carbon black composition of  claim 2  to the polymer composition. 
     
     
         10 . The method of  claim 8 , wherein the polymer is a synthetic or natural rubber. 
     
     
         11 . A method of using the carbon black composition of  claim 2  as an additive for a polymer composition, comprising the step of adding the carbon black composition to the polymer composition. 
     
     
         12 . A method of using the carbon black composition of  claim 2  for improving wear resistance and reinforcement of a polymer composition, comprising the step of adding the carbon black composition to the polymer composition. 
     
     
         13 . The method of  claim 11 , wherein the polymer is a synthetic or natural rubber. 
     
     
         14 . A method of using the carbon black composition of  claim 2  as a pigment, comprising the step of adding the carbon black composition as the pigment to a composition. 
     
     
         15 . A polymer composition comprising the carbon black composition of  claim 2 . 
     
     
         16 . A pneumatic tire comprising the carbon black composition of  claim 2 .