Non-staining polymer composite product

Abstract

A polymeric composite is provided which has improved stain preventative properties by virtue of inclusion of at least one compound having multiple functional groups capable of reacting with tannins contained in a tannin containing cellulosic material present in the composite, and a method for its production and prevention of water stains thereon.

1 . A polymeric composite product, comprising: 
 a polymer matrix;    a tannin containing cellulosic material;    calcium carbonate; and    an amount of a compound, having at least two functional groups capable of reacting with tannins present in said tannin containing cellulosic material, sufficient to prevent leaching and deposition of said tannins on a surface of the product when contacted with water.    
   
   
       2 . The polymeric composite product of  claim 1 , wherein said polymer matrix is a polymer selected from the group consisting of thermoplastic and thermosetting resins.  
   
   
       3 . The polymeric composite product of  claim 2 , wherein said polymer matrix is a polymer selected from the group consisting of polyvinyl chloride (PVC), polyethylene, polypropylene, nylon, polyesters, polysulfones, polyphenylene oxide, polyphenylene sulfide, epoxies, cellulosics, and mixtures and blends thereof.  
   
   
       4 . The polymeric composite product of  claim 3 , wherein said polymer matrix is PVC.  
   
   
       5 . The polymeric composite product of  claim 1 , wherein said tannin containing cellulosic material is a member selected from the group consisting of cellulosic fibers and cellulosic flours.  
   
   
       6 . The polymeric composite product of  claim 4 , wherein said tannin containing cellulosic material is a member selected from the group consisting of cellulosic fibers and cellulosic flours obtained from a source selected from the group consisting of recycled papers, soft woods and hard woods.  
   
   
       7 . The polymeric composite product of  claim 5 , wherein said tannin containing cellulosic material is a wood flour.  
   
   
       8 . The polymeric composite product of  claim 6 , wherein said wood flour is oak flour.  
   
   
       9 . The polymeric composite product of  claim 1 , wherein said compound having at least two functional groups is a member selected from organic diacids and anhydrides thereof.  
   
   
       10 . The polymeric composite product of  claim 8 , wherein said compound having at least two functional groups is a member selected from the group consisting of succinic acid, succinic anhydride, maleic acid, maleic anhydride, glutaric acid, glutaric anhydride, adipic acid, phthalic acid and phthalic anhydride.  
   
   
       11 . The polymeric composite product of  claim 1 , wherein said polymer matrix is PVC, said tannin containing cellulosic material is oak flour and said compound having at least two functional groups is succinic anhydride.  
   
   
       12 . A polymer composite product, comprising: 
 from 35 to 75 wt % of PVC;    from 25 to 65 wt % of oak flour;    a non-zero amount of calcium carbonate up to about 15 wt % based on PVC content; and    from 0.1-5% of succinic anhydride.    
   
   
       13 . A method for preventing staining of polymeric composites, comprising: 
 combining a polymeric composite product comprising a polymer matrix and a tannin-containing cellulosic material, with an amount of at least one compound, having at least two functional groups capable of reacting with tannins present in said tannin containing cellulosic material, sufficient to prevent leaching and deposition of said tannins on a surface of the polymeric composite when contacted with water.    
   
   
       14 . The method of  claim 13 , wherein said combining step occurs in an extruder during extrusion of said polymeric composite.  
   
   
       15 . The method of  claim 13 , wherein said polymer matrix is a polymer selected from the group consisting of thermoplastic and thermosetting resins.  
   
   
       16 . The method of  claim 15 , wherein said polymer matrix is a polymer selected from the group consisting of, polyvinyl chloride (PVC), polyethylene, polypropylene, nylon, polyesters, polysulfones, polyphenylene oxide, polyphenylene sulfide, epoxies, cellulosics, and mixtures and blends thereof.  
   
   
       17 . The method of  claim 16 , wherein said polymer matrix is PVC.  
   
   
       18 . The method of  claim 13 , wherein said tannin containing cellulosic material is a member selected from the group consisting of cellulosic fibers and cellulosic flours.  
   
   
       19 . The method of  claim 18 , wherein said tannin containing cellulosic material is a member selected from the group consisting of cellulosic fibers and cellulosic flours obtained from a source selected from the group consisting of recycled papers, soft woods and hard woods.  
   
   
       20 . The method of  claim 19 , wherein said tannin containing cellulosic material is a wood flour.  
   
   
       21 . The method of  claim 20 , wherein said wood flour is oak flour.  
   
   
       22 . The method of  claim 13 , wherein said compound having at least two functional groups is a member selected from organic diacids and anhydrides.  
   
   
       23 . The method of  claim 22 , wherein said compound having at least two functional groups is a member selected from the group consisting of succinic acid, succinic anhydride, maleic acid, maleic anhydride, glutaric acid, glutaric anhydride, adipic acid, phthalic acid and phthalic anhydride.  
   
   
       24 . The method of  claim 13 , wherein said polymer matrix is PVC, said tannin containing cellulosic material is oak flour and said compound having at least two functional groups is succinic anhydride.