Non-curling reinforced composite membranes with differing opposed faces, methods for producing and their use in varied applications

Abstract

A double-faced PTFE-silicone rubber reinforced composite with curling tendency controlled is achieved by coating one side of a balanced PTFE/glass composite with liquid silicone rubber. Each face of the composite can perform independent functions in a single application, thereby optimizing performance.

1 . A fiber-reinforced flexible composite comprising: 
 a reinforcement material;    a first exposed face on a first side of the reinforcement material, the first exposed face formed from a first material, the first material having, 
 a low coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.; and  
   a second exposed face on a second side of the reinforcement material opposing the first exposed face, the second exposed face formed from a second material, the second material having, 
 a high coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.;  
   wherein the flexible composite lies flat and does not tend to curl.    
     
     
         2 . The composite of  claim 1 , wherein the composite comprises about a same flexural modulus when it includes the second material that it comprises when it does not include the second material.  
     
     
         3 . The composite of  claim 1 , wherein the second material is a portion of a first layer having a thickness of up to about 50 mil.  
     
     
         4 . The composite of  claim 3 , wherein the first layer has a thickness of at least about 2 mil.  
     
     
         5 . The composite of  claim 1 , wherein the first material is present on the second side of the reinforcement material.  
     
     
         6 . The composite of  claim 5 , wherein the first material is only located on the first side of the reinforcement material.  
     
     
         7 . The composite of  claim 1 , wherein 
 the flexible composite comprises two compositionally distinct opposing faces;    the reinforcement material consists essentially of glass fibers;    the first material comprises a perfluoropolymer material, 
 the first material being located on each side of the reinforcement material,  
 the perfluoropolymer in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement such that it helps to prevent the membrane from curling; and  
   the second material comprises an elastomer disposed over the first material on one side of the reinforcement.    
     
     
         8 . The composite of  claim 1 , wherein 
 the composite comprises two compositionally distinct opposing faces;    the first material comprises perfluoropolymer;    the composite comprises a first layer comprising the first material and a second layer of perfluoropolymer material;    the reinforcement material is a fibrous reinforcement material and is intermediate the first and second layers;    the second material comprises an elastomer;    the second material is disposed over the second layer of perfluropolymer material; and    the first and second layers have a thickness sufficient to inhibit the composite from curling.    
     
     
         9 . The composite of  claim 1 , wherein 
 the composite comprises, 
 two compositionally distinct opposing faces;  
 a fibrous reinforcement material; and  
 a perfluoropolymer material coating on each side of the fibrous reinforcement material;  
   the first material comprises a perfluropolymer material;    the perfluoropolymer material coating on each side of the fibrous reinforcement material is in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement to prevent the membrane from curling;    the second material comprises an elastomer;    the second material is disposed over the perfluoropolymer material on one side of the fibrous reinforcement material; and    the second material has a thickness of about 2 to about 50 mils.    
     
     
         10 . The composite of  claim 1 , wherein 
 the composite comprises, 
 two compositionally distinct opposing faces;  
 a fibrous reinforcement material; and  
 a perfluoropolymer material coating on each side of the fibrous reinforcement material;  
   the first material comprises a perfluropolymer material;    the perfluoropolymer material coating on each side of the fibrous reinforcement material is in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement to prevent the membrane from curling;    the second material comprises an elastomer;    the second material is disposed over the perfluoropolymer material on one side of the fibrous reinforcement material; and    the weight ratio of the reinforcement to the perfluoropolymer coating is 50:50.    
     
     
         11 . The composite of  claim 1 , wherein the first material comprises a first layer having a thickness of at least 1 mil.  
     
     
         12 . The composite of  claim 11 , wherein the first layer has a thickness of up to about 5 mil.  
     
     
         13 . The composite of  claim 1 , wherein the first material comprises a layer having a thickness of up to 5 mil.  
     
     
         14 . The composite of  claim 1 , wherein the first material and the second material both have low surface energies.  
     
     
         15 . The composite of  claim 1 , wherein the second face is slippery when water is present and tacky when dry.  
     
     
         16 . The composite of  claim 1 , wherein the second face has pronounced stick-slip and the first face has minimal stick-slip.  
     
     
         17 . The composite of  claim 1 , comprising protuberances raised above the second exposed face.  
     
     
         18 . The composite of  claim 1 , wherein the composite has a weight of about 7.5 ounces per square inch (osy).  
     
     
         19 . The composite of  claim 1 , wherein the reinforcement member consists essentially of glass fiber.  
     
     
         20 . The composite of  claim 1 , wherein the first material comprises a perfluoropolymer and the second material comprises an elastomer.  
     
     
         21 . An article for modifying surface, comprising: 
 a flexible composite comprising 
 a reinforcement material;  
 a first exposed face on a first side of the reinforcement material, the first exposed face formed from a first material, the first material having, 
 a low coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.; and  
 
 a second exposed face on a second side of the reinforcement material opposing the first exposed face, the second exposed face formed from a second material, the second material having, 
 a high coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.;  
 
   wherein the flexible composite lies flat and does not tend to curl; and    wherein the article is configured to be placed on the surface such that the properties of the face of the material not in contact with the surface are different than the properties of the surface.    
     
     
         22 . The article of  claim 21 , wherein the first surface of the flexible composite is configured to be placed in contact with the surface such that the first face is not in contact with the surface.  
     
     
         23 . The article of  claim 21 , wherein the first material is formed on the first surface in a layer at least about 1 mil thick.  
     
     
         24 . The article of  claim 21 , wherein the second material is formed on the second surface in a layer up to about 50 mil thick.  
     
     
         25 . The article of  claim 21 , wherein the first material consists essentially of polyfluoropolymer and the second material consists essentially of elastomer.  
     
     
         26 . The article of  claim 21 , wherein the first material is also disposed on the second side of the reinforcement material.  
     
     
         27 . The article of  claim 21 , wherein 
 the first material comprises polyfluoropolymer and the second material comprises elastomer;    the first material is also disposed on the second side of the reinforcement material; and    the second material is not disposed on the first side of the reinforcement material.    
     
     
         28 . The article of  claim 27 , wherein 
 the first material is formed on the first surface in a layer at least about 1 mil thick; and    the second material is formed on the second surface in a layer up to about 50 mil thick.    
     
     
         29 . A flexible composite based belt, the belt comprising: 
 a reinforcement material;    a first exposed face on a first side of the reinforcement material, the first exposed face formed from a first material, the first material having, 
 a low coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.; and  
   a second exposed face on a second side of the reinforcement material opposing the first exposed face, the second exposed face formed from a second material, the second material having, 
 a high coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.;  
   wherein the belt lies flat and does not tend to curl.    
     
     
         30 . The belt of  claim 29 , wherein 
 the flexible composite comprises two compositionally distinct opposing faces;    the reinforcement material consists essentially of glass fibers;    the first material comprises a perfluoropolymer material, 
 the first material being located on each side of the reinforcement material,  
 the perfluoropolymer in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement such that it helps to prevent the membrane from curling; and  
   the second material comprises an elastomer disposed over the first material on one side of the reinforcement.    
     
     
         31 . The belt of  claim 29 , wherein 
 the composite comprises two compositionally distinct opposing faces;    the first material comprises perfluoropolymer;    the composite comprises a first layer comprising the first material and a second layer of perfluoropolymer material;    the reinforcement material is a fibrous reinforcement material and is intermediate the first and second layers;    the second material comprises an elastomer;    the second material is disposed over the second layer of perfluropolymer material; and    the first and second layers have a thickness sufficient to inhibit the composite from curling.    
     
     
         32 . The belt of  claim 29 , wherein 
 the composite comprises, 
 two compositionally distinct opposing faces;  
 a fibrous reinforcement material; and  
 a perfluoropolymer material coating on each side of the fibrous reinforcement material;  
   the first material comprises a perfluropolymer material;    the perfluoropolymer material coating on each side of the fibrous reinforcement material is in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement to prevent the membrane from curling;    the second material comprises an elastomer;    the second material is disposed over the perfluoropolymer material on one side of the fibrous reinforcement material; and    the second material has a thickness of about 2 to about 50 mils.    
     
     
         33 . The belt of  claim 29 , wherein 
 the composite comprises, 
 two compositionally distinct opposing faces;  
 a fibrous reinforcement material; and  
 a perfluoropolymer material coating on each side of the fibrous reinforcement material;  
   the first material comprises a perfluropolymer material;    the perfluoropolymer material coating on each side of the fibrous reinforcement material is in a balanced state having mechanical forces within the perfluoropolymer equal on each side of the reinforcement to prevent the membrane from curling;    the second material comprises an elastomer;    the second material is disposed over the perfluoropolymer material on one side of the fibrous reinforcement material; and    the weight ratio of the reinforcement to the perfluoropolymer coating is 50:50.    
     
     
         34 . The belt of  claim 29 , wherein the belt comprises about a same flexural modulus when it includes the second material that it comprises when it does not include the second material.  
     
     
         35 . An apparatus comprising: 
 a machine; and    a belt capable of being driven by the machine, the belt comprising, 
 a reinforcement material;  
 a first exposed face on a first side of the reinforcement material, the first exposed face formed from a first material, the first material having, 
 a low coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.; and  
 
 a second exposed face on a second side of the reinforcement material opposing the first exposed face, the second exposed face formed from a second material, the second material having, 
 a high coefficient of friction, and  
 thermal stability in operating environments exceeding 350° F.;  
 
 wherein the belt lies flat and does not tend to curl.  
   
     
     
         36 . The apparatus of  claim 35 , wherein 
 the machine comprises a heated platen;    the machine and belt are configured such that the first exposed face will move across the heated platen and the second exposed face will be in contact with objects.    
     
     
         37 . The apparatus of  claim 35 , wherein the machine and belt are configured such that the second exposed face will be in contact with objects and the belt will move the objects along an incline.  
     
     
         38 . A fiber-reinforced flexible composite comprising: 
 a fibrous reinforcement material;    a first exposed face on a first side of the fibrous reinforcement material, the first exposed face formed from a first material comprising perfluropolymer, the first material having, 
 a low coefficient of friction,  
 thermal stability in operating environments exceeding 350° F.,  
 minimal stick-slip, and  
 a low surface energy; and  
   a layer on a second side of the fibrous reinforcement material, the layer formed from a second material comprising a perfluoropolymer, the second material having, 
 a low coefficient of friction,  
 thermal stability in operating environments exceeding 350° F., and  
 a low surface energy; and  
   a second exposed face, on the second side of the reinforcement material, opposing the first exposed face, the second exposed face formed from a third material comprising an elastomer, the third material having, 
 a high coefficient of friction,  
 thermal stability in operating environments exceeding 350° F.,  
 pronounced stick-slip, and  
 a low surface energy;  
   wherein the flexible composite lies flat and does not tend to curl;    wherein the composite comprises about a same flexural modulus when it includes the second material that it comprises when the composite does not include the second material; and    wherein the composite comprises two compositionally distinct opposing faces.    
     
     
         39 . The composite of  claim 38 , wherein 
 the third material is not located on the first side of the reinforcement material;    the third material is a portion of a layer having a thickness of up to 50 mil; and    the first material is present on the first side with a thickness of 1 mil to 5 mil.    
     
     
         40 . The composite of  claim 38 , wherein the first material and the second material are a same type of material and the third material is bonded to the second material.