Recyclable, self-cleaning cellulose-fiber composites

Abstract

Disclosed are composite paper materials comprising hydrophobic fluorocarbons. Also disclosed are passive cooling materials comprising the composite paper materials. Further disclosed are methods of making the composite paper materials.

1 . A paper, comprising:
 cellulose fibers; and a hydrophobic fluorocarbon;   wherein the amount of the hydrophobic fluorocarbon is about 0.1 wt % to about 5 wt % of the paper.   
     
     
         2 . The paper of  claim 1 , wherein the hydrophobic fluorocarbon is polytetrafluoroethylene. 
     
     
         3 . The paper of  claim 1 , wherein the hydrophobic fluorocarbon is 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane. 
     
     
         4 . The paper of  claim 1 , further comprising a dye. 
     
     
         5 . The paper of  claim 4 , wherein the dye is a food dye. 
     
     
         6 . The paper of  claim 5 , wherein the food dye is brilliant blue (E133), indigo carmine (E132), tartrazine (E102), sunset yellow FCF (E110), or Allura Red AC (E129). 
     
     
         7 . The paper of  claim 1 , further comprising hemicellulose and lignin. 
     
     
         8 . (canceled) 
     
     
         9 . The paper of  claim 1 , wherein the cellulose fibers have an average fiber diameter of about 5 μm to about 50 μm. 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . The paper of  claim 1 , wherein the cellulose fibers have an average fiber length of about 1 mm to about 5 mm. 
     
     
         13 . The paper of  claim 1 , wherein the cellulose fibers form a porous material having an average pore size of about 10 μm to about 30 μm. 
     
     
         14 . The paper of  claim 1 , wherein the hydrophobic fluorocarbon is in the form of a plurality of particles having an average particle diameter of about 0.5 μm to about 2.5 μm. 
     
     
         15 . (canceled) 
     
     
         16 . The paper of  claim 1 , wherein the paper has a thickness of about 0.1 mm to about 15 mm. 
     
     
         17 . The paper of  claim 16 , wherein the paper has a thickness of about 1 mm to about 3 mm. 
     
     
         18 . The paper of  claim 1 , wherein at least one surface of the paper is impervious to water. 
     
     
         19 . The paper of  claim 1 , wherein the paper is planar. 
     
     
         20 . The paper of  claim 19 , wherein the cellulose fibers form a planar layer, comprising a first planar surface and a second planar surface; and the hydrophobic fluorocarbon coats the first planar surface of the planar layer. 
     
     
         21 . The paper of  claim 20 , wherein the hydrophobic fluorocarbon coats the second planar surface of the planar layer. 
     
     
         22 . (canceled) 
     
     
         23 . A passive cooling material, comprising the paper of  claim 1 . 
     
     
         24 - 31 . (canceled) 
     
     
         32 . A method for making the paper of  claim 1 , comprising:
 mixing cellulose fibers, a hydrophobic fluorocarbon, and water, thereby forming a pulp;   pressing the pulp, thereby forming a pressed pulp; and   drying the pressed pulp, thereby forming the paper.   
     
     
         33 - 50 . (canceled) 
     
     
         51 . A method for making the paper of  claim 1 , comprising:
 mixing cellulose fibers and water, thereby forming a pulp;   pressing the pulp, thereby forming a pressed pulp;   drying the pressed pulp, thereby forming the paper; and   spraying the paper with a hydrophobic fluorocarbon.   
     
     
         52 - 69 . (canceled)