Synthesis and viscoelastic properties of Ni carboxylato-telechelic polyoxirane

Viscoelastic properties of Ni carboxylato-telechelic polyoxirane have been reported to depend on both the polarity of the polymer matrix and the neutralization pathway, i.e., the use of an excess of NiAc₂ according to a one-step neutralization or a two-step process consisting of the stoichiometric end-neutralization of the acid end-groups followed by the addition of the salt excess. It has been found that the association of Ni carboxylate ion-pairs prevails over potential coordinative interactions of Ni with carboxylate and ether ligands. An excess of NiAc₂ is favorable to the end-group aggregation and increases the efficiency of the crosslinking effect.