Patent ID: 8026306

Claim:
A polymeric chelating agent comprising a polymer chain of either general formulae (1) or (2) containing pyridine-N-oxide, quinoline-N-oxide or isoquinoline-N oxide pendent ligand groups A, where m and n are independent integers in the range of from 1 to 10, and the number average molecular weight of the polymers lies in the range from 1×10 3 to 5×10 5 : wherein each pendent group A in formulae (1) and (2) is a member selected from the group consisting of and, wherein each side chain B in formula (2) is a member selected from the group consisting of and, wherein each ring substituent R 1 to R 6 is a member selected from the group consisting of H, F, Cl, Br, CF 3 , CN, CH 3 , C 2 H 5 , CO 2 H and CO 2 R 7 , where R 7 is a linear or branched C 1 to C 4 alkyl group.