MOLECULAR-ORIENTATION OF ALKYL-AROMATIC POLYIMIDE THIN-FILMS PREPAREDBY VAPOR-DEPOSITION POLYMERIZATION

Molecular oriented alkyl-aromatic polyimide thin films were prepared i n vacuo. First, alkyl-aromatic poly(amic acid) films were prepared fro m 1,10-diaminodecane and pyromellitic dianhydride by vapour deposition polymerization. Next the poly(amic acid) thin films were imidized to polyimide films by annealing. The X-ray diffraction patterns and the I R spectra indicated that the molecular chains both in the poly(amic ac id) films and in the polyimide films were aligned perpendicular to the substrate surface. Annealing the films gave rise to not only imidizat ion but also reorientation of the molecular chains and re-evaporation of the monomer and the oligomer.