Desirable hydrophobic monomers for use in the ion-sensitive cationic polymers of the present invention include, but are not limited to, branched or linear C1-C1-8 alkyl vinyl monomers, preferably C1-C4 alkyl vinyl ethers, vinyl esters, acrylamides, acrylates, methacrylates, and other monomers that can be copolymerized with the cationic monomer.