| abstract |
A crosslinked polymer comprising: reagents of a first repeating unit, a second repeating unit, a first crosslinking agent and a second crosslinking agent that react to form the crosslinked polymer, where the first repeating unit is a sulfonic acid-containing monomer , present from 50% to 99% by weight of the reagents, where the second repeating unit is selected from the group consisting of a monomer containing N-vinylamide, a monomer containing a double terminal bond, and any combination thereof, and from 1% to 50% by weight of the reagents is present, wherein the first crosslinking agent comprises at least two olefinic bonds, where the second crosslinking agent comprises at least two olefinic bonds, and where the first crosslinking agent and the second agent Combined crosslinkers are present in the range of about 0.01% to about 25% by weight of the reagents. |