The capability of ring-opening metathesis polymerization (ROMP) to efficiently incorporate bulky monomers and conserve olefin bonds during polymerization was exploited to design water-soluble fluoropolymers, which were evaluated as potential quantitative F-19 magnetic resonance imaging (MRI) contrast agents. The fluoromonomeric units comprised 3, 6, 9, or 18 magnetically equivalent fluorine atoms. Aqueous solubility was achieved through dihydroxylation of the partially unsaturated polymeric backbone and by tetraethylene glycol (TEG)-based linker incorporation, ammonium quaternization, or copolymerization.