Composite Friction Materials Having Carbon Nanotube and Carbon Nanofiber Friction Enhancers

Abstract

A textile-reinforced composite friction material is provided by the present invention that includes a nonwoven needlepunched fiber mat, a resin matrix impregnated within and onto the fiber mat, and a carbon nanomaterial dispersed within the resin matrix. The carbon nanomaterial is preferably carbon nanotubes and/or carbon nanofibers.

1 . A composite friction material comprising:
 a nonwoven needlepunched fiber mat;   a resin matrix impregnated in the fiber mat; and   a carbon nanomaterial dispersed on and within the resin matrix and fiber mat.   
     
     
         2 . The composite friction material according to  claim 1 , wherein the carbon nanomaterial is selected from a group consisting of carbon nanotubes and carbon nanofibers. 
     
     
         3 . The composite friction material according to  claim 2 , wherein the carbon nanomaterial defines between approximately 0.004 and approximately 0.080 by volume fraction of the composite friction material. 
     
     
         4 . The composite friction material according to  claim 1 , wherein the carbon nanomaterial defines between approximately 0.004 and approximately 0.080 by volume fraction of the composite friction material. 
     
     
         5 . The composite friction material according to  claim 1  further comprising fillers dispersed within the resin. 
     
     
         6 . The composite friction material according to  claim 1 , wherein the resin matrix is selected from a group consisting of polyimide, phenolic, and epoxy. 
     
     
         7 . The composite friction material according to  claim 1 , wherein the fiber mat is selected from a group comprising aramid, glass, ceramic, polyacrylnitrile and staple carbon or staple graphite fibers. 
     
     
         8 . A friction product for use in a friction application comprising:
 a backing; and   a friction composite attached to the backing, the friction composite comprising a dispersed carbon nanomaterial within a matrix carrier.   
     
     
         9 . The friction product according to  claim 8 , wherein the carbon nanomaterial is selected from the group consisting of carbon nanotubes and carbon nanofibers. 
     
     
         10 . The friction product according to  claim 8 , wherein the friction product is selected from the group consisting of a dry brake plate, a wet brake plate, a clutch plate, a transmission friction disc, a transmission band, a brake band, a torque converter lining, a slip differential or synchronizer friction element, and a brake pad or block, among others. 
     
     
         11 . The friction product according to  claim 8 , wherein the composite comprises a resin matrix impregnated within and onto a nonwoven needlepunched textile-reinforced fiber mat. 
     
     
         12 . The friction product according to  claim 8 , wherein the backing substrate is metal. 
     
     
         13 . The friction product according to  claim 8 , wherein the backing substrate is plastic. 
     
     
         14 . The friction product according to  claim 8 , wherein the friction element is a lining, facing, or unattached member. 
     
     
         15 . The friction product according to  claim 10 , wherein the friction element is a facing. 
     
     
         16 . A composite material for use in friction applications comprising a nonwoven needle punched fiber mat;
 a resin matrix impregnated in the fiber mat; and   a carbon nanomaterial dispersed on and within the resin matrix and fiber mat, the carbon nanomaterial selected from the group consisting of carbon nanotubes and carbon nanofibers.   
     
     
         17 . The composite material according to  claim 16 , wherein the carbon nanomaterial defines between approximately 0.004 and approximately 0.080 by volume fraction of the composite material. 
     
     
         18 . A composite friction material comprising:
 a carded and needlepunched fiber mat is selected from a group comprising aramid, glass, ceramic, polyacrylonitrile and staple carbon or staple graphite fibers;   a resin matrix impregnated within the fiber mat; and   a carbon nanomaterial selected from the group consisting of carbon nanotubes and carbon nanofibers dispersed within the resin matrix.   
     
     
         19 . The composite friction material according to  claim 18  wherein the carbon nanomaterial defines between approximately 0.004 and approximately 0.080 by volume fraction of the composite friction material. 
     
     
         20 . A method of forming a composite friction material comprising preparing a fiber mat, dispersing a carbon nanomaterial selected from the group consisting of carbon nanotubes and carbon nanofibers within a resin, and saturating the fiber mat with resin containing the nanomaterial. 
     
     
         21 . The method according to  claim 20  further comprising separating the particles of the nanomaterial in a solvent before dispersing the nanomaterial within the resin. 
     
     
         22 . The method according to  claim 20  further comprising dispersing the nanomaterial and resin in the mat by a method selected from the group consisting of compression rolling and squeezing. 
     
     
         23 . The method according to  claim 22  further comprising dispersing the nanomaterial and resin in the mat by vacuum impregnation 
     
     
         24 . The method according to  claim 20  further comprising multiple steps of dispersing the nanomaterial within the resin and saturating the fiber mat. 
     
     
         25 . The method according to  claim 24 , wherein the multiple steps of dispersing the nanomaterial within the resin and saturating the fiber mat are alternated with application of vacuum. 
     
     
         26 . A method of forming a composite friction material preform comprising depositing a carbon nanomaterial onto a fiber mat during the needlepunching process. 
     
     
         27 . A friction product made by the method of  claim 26   
     
     
         28 . A method of forming a composite friction material comprising depositing a carbon nanomaterial onto a fiber mat and impregnating the carbon nanomaterial fiber mat with a resin. 
     
     
         29 . A friction product made by the method of  claim 28 .