Preparation and characterizations of soluble regularly alternating polyazomethines from oligothienylenes

The preparation and characterization of oligothienylene dialdehydes and related soluble copolymers in which thenylenic segments regularly alternate with phenylenic portions linked by azomethine moieties is presented. The polymer series with three, six and eight thienylenic residues showed interesting evidences of electronic confinement in low-gap segments (thienylenic). Self-assembled structures of oligomers can be obtained either by evaporation in high vacuum or by a proper thermal treatment of spin coated films, depending on the molecule length. Polymers prepared by different synthetic routes show different thermal and structural properties as a function of the ratio of two possible isomers at imino linkage. The order degree also influences the optical properties in fact luminescence data are strictly related to the percentage of the two isomers.