Tire having rubber component containing short fiber reinforcement with compatablizer

Abstract

The invention relates to a tire having a rubber component which contains short fiber reinforcement with a compatabilizer for the fiber reinforcement. Desirably said short fiber reinforcement is an aramid pulp. Desirably said compatabilizer is an epoxy functionalized natural rubber.

1 . A tire having a component of a rubber composition containing a dispersion therein of short organic fibers comprised of, based on parts by weight per 100 parts by weight rubber (phr):
 (A) 100 phr of conjugated diene-based elastomers comprised of:
 (1) from zero to about 95 phr of at least one of polymers and copolymers of isoprene and 1,3-butadiene and copolymers of styrene with at least one of isoprene and 1,3-butadiene as non-functionalized elastomers, and 
 (2) about 5 to about 100 phr of functionalized sulfur curable elastomer as a compatiblizer for said short organic fibers within said rubber composition comprised of at least one of polymers and copolymers of isoprene and 1,3-butadiene and copolymers of styrene with at least one of isoprene and 1,3-butadiene having at least one functional group interactive with said organic fibers comprised of at least one of epoxy groups, amine groups, hydroxyl groups, carboxyl groups, maleic group and maleimide group; 
   (B) about 30 to about 100 phr of particulate reinforcement comprised of:
 (1) rubber reinforcing carbon black, or 
 (2) synthetic amorphous precipitated silica, or 
 (3) combination of rubber reinforcing carbon black and synthetic amorphous precipitated silica containing up to about 80 phr of said precipitated silica together with a silica coupler for said precipitated silica; 
   (C) about 0.5 to about 30 phr of said short organic fibers wherein said short organic fibers are comprised of at least one of aramid fiber, polyester fiber, nylon fiber and rayon fiber.   
     
     
         2 . The tire of  claim 1  wherein said rubber composition also contains up to about 50 phr of at least one of clay and calcium carbonate. 
     
     
         3 . The tire of  claim 1  wherein said rubber compositions contains at least one of clay and calcium carbonate in amounts of up to about 10 phr of clay and up to about 50 phr of calcium carbonate. 
     
     
         4 . The tire of  claim 1  wherein said short organic fiber is comprised of short aramid fiber pulp. 
     
     
         5 . The tire of claim wherein said functionalized sulfur curable elastomer is comprised of expoxidized cis 1,4-polyisoprene rubber. 
     
     
         6 . The tire of  claim 1  wherein said functionalized sulfur curable elastomer is comprised of expoxidized cis 1,4-polyisoprene rubber having an expoxidation in a range of from about 5 to about 60 percent and said short organic fiber is comprised of short aramid fiber pulp. 
     
     
         7 . The tire of  claim 1  wherein said rubber composition is comprised of from about 10 to about 95 phr of at least one of cis 1,4-polyisoprene rubber, cis 1,4-polybutadiene rubber and styrene/butadiene rubber and from about 5 to about 90 phr of at least one of functionalized cis 1,4-polyisoprene rubber and functionalized styrene/butadiene rubber functionalized with at least functional group reactive with said organic fibers comprised of at least one of epoxy groups, amine groups, hydroxyl groups and carboxyl groups. 
     
     
         8 . The tire of  claim 7  wherein said functionalized sulfur curable elastomer is comprised of expoxidized cis 1,4-polyisoprene rubber having an expoxidation in a range of from about 5 to about 60 percent and said short organic fiber is comprised of short aramid fiber pulp. 
     
     
         9 . The tire of  claim 1  wherein said particulate reinforcement is comprised of rubber reinforcing carbon black. 
     
     
         10 . The tire of  claim 1  wherein said particulate reinforcement is comprised of synthetic amorphous precipitated silica. 
     
     
         11 . The tire of  claim 1  wherein said particulate reinforcement is comprised of said combination of rubber reinforcing carbon black and synthetic amorphous precipitated silica. 
     
     
         12 . The tire of  claim 1  wherein said short organic fiber is comprised of at least one of aramid and polyester fiber. 
     
     
         13 . The tire of  claim 7  wherein said particulate reinforcement is comprised of said combination of rubber reinforcing carbon black and synthetic amorphous precipitated silica and wherein said short organic fiber is comprised of at least one of aramid and polyester fiber. 
     
     
         14 . A method of preparing a rubber composition comprised of, based on parts by weight per 100 parts by weight rubber (phr):
 (A) 100 phr of conjugated diene-based elastomers comprised of:
 (1) from zero to about 95 phr of at least one of polymers and copolymers of isoprene and 1,3-butadiene and copolymers of styrene with at least one of isoprene and 1,3-butadiene as non-functionalized elastomers, and 
 (2) about 5 to about 100 phr of functionalized sulfur curable elastomer as a compatiblizer for said short organic fibers within said rubber composition comprised of at least one of polymers and copolymers of isoprene and 1,3-butadiene and copolymers of styrene with at least one of isoprene and 1,3-butadiene having at least one functional group interactive with said organic fibers comprised of at least one of epoxy groups, amine groups, hydroxyl groups, carboxyl groups, maleic group and malemide group; 
   (B) about 30 to about 100 phr of particulate reinforcement comprised of:
 (1) rubber reinforcing carbon black, or 
 (2) synthetic amorphous precipitated silica, or 
 (3) combination of rubber reinforcing carbon black and synthetic amorphous precipitated silica containing up to about 80 phr of said precipitated silica together with a silica coupler for said precipitated silica; 
   (C) about 0.5 to about 30 phr of said short organic fibers wherein said short organic fibers are comprised of at least one of aramid fiber, polyester fiber, nylon fiber and rayon fiber;   wherein said method is comprised of:
 (1) mixing said short organic fibers and said compatiblizer elastomer with said rubber composition to enable said compatiblizer elastomer to compatiblize said short organic fibers with said elastomers of said rubber composition in situ with said rubber composition, or 
 (2) mixing a pre-formed masterbatch with said rubber composition wherein said master batch is comprised of a dispersion of said organic short fibers blended with as least one of said functionalized elastomers, or 
 (3) mixing a pre-formed masterbatch with said rubber composition wherein said masterbatch is comprised of at least one of said organic short fibers and least one of said functionalized elastomer as:
 (a) a coagulated functionalized elastomer from a latex thereof, or 
 (b) a recovered functionalized elastomer from an organic solution thereof. 
 
   
     
     
         15 . The method of  claim 14  wherein said functionalized elastomer is an epoxidized cis 1,4-polyisoprene having an epoxidation in a range of from about 5 to about 60 percent and said short organic fiber is comprised of aramid fiber pulp. 
     
     
         16 . A rubber composition prepared by the method of  claim 14 . 
     
     
         17 . A tire having a component comprised of the rubber composition of  claim 16 . 
     
     
         18 . The method of  claim 14  comprised of mixing said short organic fibers and said compatiblizer elastomer with said rubber composition to enable said compatiblizer elastomer to compatiblize said short organic fibers with said elastomers of said rubber composition in situ with said rubber composition. 
     
     
         19 . The method of  claim 14  comprised of mixing a pre-formed masterbatch with said rubber composition wherein said master batch is comprised of a dispersion of said organic short fibers blended with as least one of said functionalized elastomers. 
     
     
         20 . The method of  claim 14  comprised of mixing a pre-formed masterbatch with said rubber composition wherein said masterbatch is comprised of at least one of said organic short fibers and at least one of said functionalized elastomers as a coagulated functionalized elastomer from a latex thereof.