Marine coatings

1. A marine substrate, comprising a polymer coating, wherein the polymer has the formula:

PB-(L 1 -N + (R a )(R b )-L 2 -A(=O)−OR c ) n (X − ) n

wherein

PB is a polymer backbone;

N + is a cationic center;

R a and R b are independently selected from hydrogen, alkyl, and aryl;

A(=O)—OR c is a hydrolyzable group, wherein A is selected from the group consisting of C, S, SO, P, or PO, and R c is an alkyl, aryl, acyl, or silyl group that may be further substituted with one or more substituents;

L 1 is a linker that covalently couples the cationic center to the polymer backbone;

L 2 is a linker that covalently couples the cationic center to the hydrolyzable group; X— is a counter ion associated with the cationic center; and n is an integer from about 10 to about 10,000.

2. The marine substrate of claim 1 , wherein the counter ion is a hydrophobic organic counter ion.

3. The marine substrate of claim 1 , wherein the counter ion is selected from the group consisting of C1-C20 carboxylates and C1-C20 alkylsulfonates.

4. The marine substrate of claim 1 , wherein the counter ion is biologically active.

5. The marine substrate of claim 1 , wherein the counter ion is selected from the group consisting of an antimicrobial, an antibacterial, and an antifungal agents.

6. The marine substrate of claim 1 , wherein the counter ion is salicylate.

7. The marine substrate of claim 1 , wherein the hydrolyzable group releases a hydrophobic organic group on hydrolysis.

8. The marine substrate of claim 1 , wherein the hydrolyzable group releases a C1-C20 carboxylate on hydrolysis.

9. The marine substrate of claim 1 , wherein R a and R b are independently selected from the group consisting of C1-C10 straight chain and branched alkyl groups.

10. The marine substrate of claim 1 , wherein L 1 is selected from the group consisting of —C(═O)O—(CH 2 ) n — and —C(═O)NH—(CH 2 ) n —, wherein n is an integer from 1 to 20.

11. The marine substrate of claim 1 , wherein L 2 is —(CH 2 ) n —, where n is an integer from 1 to 20.

12. The marine substrate of claim 1 , wherein A is selected from the group consisting of C, SO, and PO.

13. The marine substrate of claim 1 , wherein R c is C1-C20 alkyl.

14. The marine substrate of claim 1 , wherein X— is selected from the group consisting of halide, carboxylate, alkylsulfonate, sulfate, nitrate, perchlorate, tetrafluoroborate, hexafluorophosphate, trifluoromethylsulfonate, bis(trifluoromethylsulfonyl)amide, lactate, and salicylate.

15. The marine substrate of claim 1 , wherein the marine substrate is a vessel hull.

16. The marine substrate of claim 1 , wherein the marine substrate is a propeller, periscope of sensor.

17. The marine substrate of claim 1 , wherein the marine substrate is a bridge.

18. The marine substrate of claim 1 , wherein the marine substrate is a fish net.

19. A method for treating a surface of a marine substrate, comprising applying a polymer coating, wherein the polymer has the formula:

PB-(L 1 -N + (R a )(R b )-L 2 -A(=O)—OR c ) n (X − ) x

wherein

PB is a polymer backbone;

N + is a cationic center;

R a and R b are independently selected from hydrogen, alkyl, and aryl;

A(=O)—OR c is a hydrolyzable group, wherein A is selected from the group consisting of C, S, SO, P, or PO, and R c is an alkyl, aryl, acyl, or silyl group that may be further substituted with one or more substituents;

L 1 is a linker that covalently couples the cationic center to the polymer backbone;

L 2 is a linker that covalently couples the cationic center to the hydrolyzable group; X— is a counter ion associated with the cationic center; and n is an integer from about 10 to about 10,000.

20. The method of claim 19 , wherein applying the coating comprises spraying the coating.

21. The method of claim 19 , wherein applying the coating comprises painting the coating.

22. The method of claim 19 , wherein the substrate is a vessel hull or marine structure.