Ion clustering in a butadiene, styrene, 4‐vinylpyridine terpolymer crosslinked by coordination with iron(III) chloride

A butadiene, styrene, 4‐vinylpyridine terpolymer has been crosslinked by coordination of the pyridine groups with iron chloride. The distribution and structure of the iron complexes have been studied. Electron microscopy has given evidence of clustering of the iron complexes. The size distribution of these clusters has been evaluated by small‐angle x‐ray and neutron scattering. Mössbauer spectroscopy and magnetization measurements have shown the presence of three different kinds of iron complexes: (a) complexes with a speromagnetic structure in the clusters previously found, (b) dimers with antiferromagnetic coupling, and (c) quasi‐isolated complexes with weak ferromagnetic coupling. The percentages of these different iron complexes have been measured.