Comb-Like Polyethylene Oxide Polymers as Chelating Agents for Mercuric (II) Chloride: Study of The Complex Formation by Solid-State 1H-NMR

Polyethylene oxide (PEO) forms with mercuric chloride a great variety of stable complexes of different stoichiometry, depending on the molecular we i ght , the type of end groups and the solvent. To take advantage of this unique property, the synthesis of hydrogels by polymerization of acrylates or methacrylates of short PEO chains (macromers) is carried out and the formation of mercuric complexes is discussed. The stoichiometry of the different complexes formed is compared and discussed in relation to the results of solid state 1H-NMR experiments us ing the free induction decay technique. It is shown that, (i) the binding properties of the gels are similar to those of PEO in solution, (ii) the first two ethylene oxyde units next to the grafting points are rather rigid and therefore are unable to participate in the complexes formation.