Surface Morphology and Molecular Arrangement of Organized Films of Poly-(N-alkylated benzamides) Containing Various Chain Lengths

Abstract

We investigated the molecular arrangement and surface morphology of organized molecular films with regard to solid-state structures for newly synthesized aromatic polyamides with various side chain length by surface pressure-area (π–A) isotherm, in-plane and out-of plane X-ray diffraction (XRD), and atomic force microscopy (AFM). Since the aromatic polyamides have rigid main chain and flexible side chain, it may be possible to form the phase separated structure at sub-nanometer scales. These polyamides form the extremely condensed monolayer on the water surface. Multilayers of these polyamides transferred by Langmuir-Blodgett (LB) method construct highly order layer structure. On the other hand, in the two-dimensional film plane of polyamides, amorphous structure of side chains is formed except for octadecyl derivatives. Changes in the surface morphology of monolayers for these polyamides definitely depend on the side chain length. Spherulitic, fibril like, and homogeneous flat morphologies of the film surface are systematically observed by AFM measurement.