Transient Metallosupamolecular Networks Built from Entangled Melts of Poly(ethylene oxide)

Goldansaz, Hadi [UCL] Auhl, D. [Maastricht University (The Netherlands)] Goderis, B. [KUL] Voleppe, Quentin [UCL] Fustin, Charles-André [UCL] Gohy, Jean-François [UCL] Bailly, Christian [UCL] Van Ruymbeke, Evelyne [UCL]

The effect of poly(ethylene oxide) [PEO]−metal salt complexation on the dynamics and microstructure of PEO−nickel chloride [NiCl2] systems is investigated by rheology and X-ray scattering. Annealed PEO−nickel salt systems exhibit network properties above the melting temperature of PEO, characterized by a second elastic plateau, beyond the reptation time of PEO chains. The level of the second plateau strongly depends on the annealing conditions and the ion content. In PEO−NiCl2 networks, the linear viscoelastic region is experimentally out of reach, meaning that their viscoelastic properties strongly depend on strain and strain rate as well as any deformation history. The network can be broken down by large-amplitude shear and reversibly reformed under quiescent conditions. X-ray scattering reveals formation of distinct crystalline structures of PEO−NiCl2 complexes, which are different from those of both neat PEO and nickel salt. The combined rheology and X-ray scattering results indicate that the network results from a small fraction of trapped PEO chains, which are bridging the crystalline domains of PEO−NiCl2 complexes