Coupling agent for elastomeric composition comprising a reinforcing filler

Abstract

A method of forming a sulfur-vulcanized elastomeric by combining at least one diene elastomer and at least one reinforcing filler, with an effective amount of a coupling agent consisting of a combination of: 10 to 90%, of a product (I) consisting of a blend of poly(alkylphenol) polysulfides of formula: in which: R is an alkyl radical containing 1 to 20 carbon atoms; n and n′ are two integers, which may be identical or different, from 1 to 8; p is an integer from 0 to 50; and 10 to 90% of a product (II) consisting of bis(triethoxysilylpropyl)tetrasulfide, to form a mixture; thereafter working said mixture; and thereafter heating said mixture to vulcanize said mixture. 90% of bis(triethoxysilylpropyl)tetrasulfide.

1 . A method of forming a sulfur-vulcanized elastomeric composition comprising the steps of:
 combining at least one diene elastomer and at least one reinforcing filler, with an effective amount of a coupling agent consisting of a combination of:   10 to 90%, of a product (I) consisting of a blend of poly(alkylphenol) polysulfides of formula:   
     
       
         
         
             
             
         
       
     
     in which:
 R is an alkyl radical containing 1 to 20 carbon atoms; 
 n and n′ are two integers, which may be identical or different, from 1 to 8; 
 p is an integer from 0 to 50; and 
 10 to 90% of a product (II) consisting of bis(triethoxysilylpropyl)tetrasulfide, to form a mixture; thereafter 
 working said mixture; and thereafter 
 heating said mixture to vulcanize said mixture. 
 
   
   
       2 . The method of  claim 1 , characterized in that said at least one or more diene elastomers is selected from the group consisting of polybutadiene and poly(styrene/butadiene. 
   
   
       3 . The method of  claim 1 , characterized in that a white reinforcing filler is used. 
   
   
       4 . The method of  claim 3 , characterized in that said white filler is selected from the group consisting of silica, alumina and mixtures thereof. 
   
   
       5 . The method of  claim 1 , characterized in that a mixture of compounds of formula (I) is used in which P is an alkyl radical containing at least one tertiary carbon via which R is linked to the aromatic ring. 
   
   
       6 . The method of  claim 5 , characterized in that R is a tert-butyl or tert-pentyl radical. 
   
   
       7 . The method of  claim 1 , characterized in that said blend of compounds of of formula (I) comprises a mixture in which the average value of n and of n′ is about 2 and the average value of p is about 5. 
   
   
       8 . The method of  claim 1 , characterized in that the (I)/(II) weight ratio is from 1 to 3. 
   
   
       9 . The method of  claim 1 , characterized in that it comprises combining:
 100 parts by weight of diene elastomer(s):   10 to 200 parts by weight of white reinforcing filler; and   0.5 to 10 parts by weight of coupling agent.   
   
   
       10 . The method of  claim 1 , characterized in that 50 to 100 parts by weight of silica and 5 to 7 parts by weight of the coupling agent are combined with 100 parts by weight of said one or more diene elastomer. 
   
   
       11 . The method of  claim 1 , characterized in that standard non-sulfur-containing additives are combined. 
   
   
       12 . The method of  claim 1 , characterized in that said working comprises mechanical working comprising at least one thermal step at a temperature of between 130° C. and 170° C. 
   
   
       13 . The method of  claim 1 , wherein 50 to 70% of said product (I) is combined. 
   
   
       14 . The method of  claim 1 , characterized in that R contains 4 to 10 carbons atoms. 
   
   
       15 . The method of  claim 1 , characterized in that n and n′ are from 1 to 4 
   
   
       16 . The method of  claim 1 , wherein 30 to 50% of said product (II) is combined. 
   
   
       17 . The method of  claim 1  characterized in that the ratio (I)/(II) is about 2. 
   
   
       22 . The method of  claim 9  wherein between 20 and 150 parts by weight said white reinforcing filler are combined.