Method for preparing modified filler, compositions and articles containing same

Abstract

Provided is a method for preparing a modified filler. The method includes in sequence providing an acidified aqueous slurry of an untreated inorganic filler which has not been previously dried; an emulsifier material; and a hydrophobating agent having the following structural formula (I): (I) Ra-M-X(4-a) wherein: R is C6 to C22 alkyl, M is silicon, titanium or zirconium, X is OR′ or N halogen, R′ is C1 to C4 alkyl, and a is 1; washing and/or filtering the acidified aqueous slurry to obtain a modified filler, and, optionally, drying the modified filler. Polymeric compositions and articles also are provided.

1 . A method for preparing a modified filler, the method comprising in sequence:
 (a) providing an acidified aqueous slurry comprising:
 (1) an untreated inorganic filler which has not been previously dried; 
 (2) an emulsifier material; and 
 (3) a hydrophobating agent having the following structural formula (I):
   R a -M-X (4-a)   (I)
 
 
   
       wherein:
 R is C 6  to C 22  alkyl, 
 M is silicon, titanium or zirconium, 
 X is OR′ or halogen, 
 R′ is C 1  to C 4  alkyl, and 
 a is 1; 
 (b) washing and/or filtering the acidified aqueous slurry of (a) to obtain a modified filler; and 
 (c) optionally, drying the modified filler. 
 
     
     
         2 . The method of  claim 1 , wherein the untreated inorganic filler (1) comprises an inorganic oxide. 
     
     
         3 . The method of  claim 1 , wherein the untreated inorganic filler (1) is selected from the group consisting of aluminum silicate, silica gel, colloidal silica, precipitated silica, and mixtures thereof. 
     
     
         4 . The method of  claim 1 , wherein the untreated filler (1) comprises precipitated silica. 
     
     
         5 . The method of  claim 1 , wherein the emulsifier material (2) is selected from the group consisting of fatty acids, salts of fatty acids, alkyl sarcosinates, salts of alkyl sarcosinates, and mixtures thereof. 
     
     
         6 . The method of  claim 1 , wherein the emulsifier material (2) is present in the aqueous slurry in an amount ranging from greater than 0 percent up to and including 0.25 percent by weight based on total weight of the slurry. 
     
     
         7 . The method of  claim 1 , wherein in structural formula (I) R is C 8  to C 20  alkyl, M is silicon, and X is OR′, wherein R′ is C 1  to C 2  alkyl. 
     
     
         8 . The method of  claim 1 , wherein the acidified aqueous slurry further comprises a coupling agent selected from the group consisting of mercaptoorganometallic compounds, sulfur-containing organometallic compounds, non-sulfur organometallic compounds, and mixtures thereof. 
     
     
         9 . The method of  claim 8 , wherein the coupling agent is selected from the group consisting of mercaptopropyltriethoxysilane, 3,3′-bis(triethoxysilylpropyl)disulfide, 3,3′-bis(triethoxysilylpropyl)polysulfides, and mixtures thereof. 
     
     
         10 . The method of  claim 1 , wherein the modified filler is dried by rotary drying techniques and/or spray drying techniques. 
     
     
         11 . A modified filler prepared by the method of  claim 1 . 
     
     
         12 . A polymeric composition comprising the modified filler of  claim 11 . 
     
     
         13 . The polymeric composition of  claim 12  which is a rubber composition. 
     
     
         14 . An article comprising the polymeric composition of  claim 12 . 
     
     
         15 . The article of  claim 14 , wherein the article is a tire.