Structure of iodine—nylon 6 complex: 4. Irregular stacking of intercalated iodine in the complex

Abstract

Oriented iodine-doped nylon 6 specimen which was prepared in an I 2KI aqueous solution was immersed into a KI aqueous solution. The ‘re-immersed’ specimen indicated an irregular intercalation of iodine stacked between hydrogen-bonded planes of nylon 6 in the complex. In the irregular stacking, iodine atoms or polyiodides are not intercalated between all of the interlayer region, while they are between each hydrogen-bonded plane of nylon 6 chains in ordinary complex; spacing of the planes is 1.95 nm in the irregular intercalation while it is 1.56 nm in the ordinary specimens. In the complex with the irregular stacking, however, the ordering along the chain axis is similar to the ordinary one. This irregular structure is induced by applying an inhibitive effect of the I − ion to prevent doping in the I 2KI aqueous solution. It suggests that the iodine—nylon 6 complex can introduce various intercalated structures such as graphite intercalation compounds.