Composite films and methods for their production

1. A composite film comprising an aryl functionalized graphane covalently bonded with a polymer.

2. The composite film of claim 1 , wherein the polymer comprises nylon, polyvinyl chloride, polystyrene, polyethylene, polypropylene, polycarbonate, poly(diallyldimethylammonium chloride) (PDDA), polyvinyl alcohol, polycaprolactone, terminal carboxylic acid groups, or any combination thereof.

3. The composite film of claim 1 , wherein the polymer comprises a functional group that covalently bonds with the aryl functionalized graphane, and wherein the aryl functionalization of the aryl functionalized graphane and the polymer each comprises a polyurethane.

4. The composite film of claim 3 , wherein the aryl functionalization of the aryl functionalized graphane comprises a first polyurethane comprising at least first and second monomer units, and the polymer comprises a second polyurethane comprising at least third and fourth monomer units, wherein at least one of the third and fourth monomer units comprises the first polyurethane.

5. The composite film of claim 4 , wherein:

the first monomer unit X is derived from a polyisocyanate, the second monomer unit Y is derived from a polyol, and the first polyurethane comprises a structural unit as represented by -[XY] m -, wherein m≧1; and

the third monomer unit Z comprises at least one carbonyl group, the fourth monomer unit comprises the first polyurethane, and the second polyurethane comprises a structural unit as represented by -[Z-[XY] m ] x -, wherein x≧1.

6. The composite film of claim 5 , wherein at least a portion of the fourth monomer unit comprises the first polyurethane.

7. The composite film of claim 3 , wherein the polymer comprises a polyurethane-polyimide.

8. The composite film of claim 7 , wherein the aryl functionalization of the aryl functionalized graphane comprises

wherein n and m are each, independently, greater than or equal to 1.

9. The composite film of claim 8 , wherein the polyurethane-polyimide has a structure as represented by

where n, m, and x are each, independently, greater than or equal to 1.

10. The composite film of claim 9 , wherein at least a portion of the

component of the polyurethane-polyimide is the same as the aryl functionalization of the aryl functionalized graphane.

11. The composite film of claim 1 , wherein the composite film has a thermal stability greater than about 300° C.

12. The composite film of claim 1 , wherein the composite film has an oxygen permeability of less than about 10 −5 g/m 2 /day.

13. The composite film of claim 1 , wherein the composite film has a water permeability of less than about 10 −6 g/m 2 /day.

14. The composite film of claim 1 , wherein the composite film has a band gap of at least about 4 electron volts.

15. A method for producing a composite film comprising a polymer covalently bonded with an aryl functionalized graphane, the method comprising:

functionalizing graphane with an aryl group that can interact with the polymer; and integrating the aryl functionalized graphane with the polymer, wherein the aryl functionalized graphane covalently bonds with the polymer.

16. The method of claim 15 , wherein functionalizing the graphane comprises exposing the graphane to at least one diazonium aryl salt to covalently bond aryl functional groups of the diazonium aryl salt to the graphane.

17. The method of claim 15 , wherein:

functionalizing the graphane comprises:

forming a prepolymer, wherein the aryl group comprises the prepolymer, the prepolymer having a structural unit as represented by -[XY] m -, wherein m≧1, X is derived from a polyisocyanate, and Y is derived from a polyol; and

functionalizing the graphane with the prepolymer; and

integrating the aryl functionalized graphane with the polymer comprises:

covalently bonding the polymer with the aryl functionalized graphane, the polymer having a structural unit as represented by -[Z-[XY] m ] x -, wherein m≧1, x≧1, Z comprises at least one additional monomeric functional group, and at least a portion of the -[XY] m - of the polymer is the same as the prepolymer of the aryl functionalized graphane.

18. The method of claim 15 , wherein functionalizing the graphane comprises:

forming a prepolymer having a structure

as the aryl group; and functionalizing the graphane with the prepolymer.

19. The method of claim 18 , wherein integrating the aryl functionalized graphane with the polymer comprises:

reacting 4,4′-diphenylmethane diisocyanate with polyoxytetramethylene glycol to form a diisocyanate prepolymer having a structure

reacting the prepolymer of the aryl functionalized graphane and the diisocyanate prepolymer with 4,4′-diphenylmethane diamine to form a polyurethane-urea having a polymeric structure of

wherein at least a portion of the

component of the polyurethane-urea is the same as the prepolymer of the graphane; and

reacting the polyurethane-urea with pyromellitic dianhydride to form an elastic polyurethane-imide having a polymeric structure of

where n, m, and x are each, independently, greater than or equal to 1.

20. An electronic device comprising a printed circuit board, wherein the printed circuit board comprises:

at least one substrate sheet comprising aryl functionalized graphane covalently bonded with a polymer; and

one or more electronic components disposed on the at least one substrate sheet.