Copper (II) Ions into Polyphosphazenes: Solid-Like Solution Behavior

Abstract

Reaction of Cu(BF4)2 salt with the polymer [NP(OC6H4C(O)C–OC6H5)2]n (1) in THF affords three new polymers gels containing varied copper (II) ions contents, (2), (3), and (4). The nature of the copper (II) ions in the gel (2)–(4) was examined by IR spectroscopy, solid state 31P, 13C and 63Cu NMR spectroscopy and EPR spectroscopy. Despite the copper content, the gels were insulators as measured by complex impedance spectroscopy. SEM images show a uniform distribution of the Cu (II) ions and a most porous morphology than those without copper polymer. TEM images show the formation of small aggregates being smallest for, gel (2) of about 200 nm. All the data suggest the Cu2+ centers behave as a solid dilute into the polyphosphazenes.