Crystal structure of poly(ethylene-oxide) supramolecular assemblies

The formation of poly(ethylene oxide) (PEO) supramolecular complexes is dis cussed in terms of intermolecular interactions and molecular packing. On th e basis of the different known crystal structures, several mechanisms are p roposed. First, the PEO complexes can be formed by an Intercalation or Incl usion process, guest molecules diffusing into the PEO unit cell. On the oth er hand, molecular complexes based on hydrogen bonding cannot be obtained b y such a way, their formation requires the complete removal of the initial PEO structure either by melting or dissolution. Finally the relations betwe en the crystal lamellar morphology, the host-guest interactions and the PEO chain mobility are discussed.