Supramolecular structures of poly(γ-benzyl-L-glutamate) self-assembled on mica surface

Abstract

This article reports the results of structural studies of poly (γ-benzyl-L-glutamate) (PBLG) layers self-assembled from dilute solutions in organic solvents on mica surface. Polarized dynamic light scattering and atomic force microscopy were used to study polymer properties in solutions and on the surface. The hierarchy of self-assembly from PBLG solutions in different solvents was investigated as a function of polymer concentration and solvent polarity. We show that the surface-polymer interaction is suppressed in polar solvents that is interpreted in terms of suppressed charge-dipole interaction. The transformation of the PBLG surface structure occurs upon addition of different amounts of trifluoroacetic acid to polymer solution in dioxane. Rigid-rod PBLG molecules experience rod-globular transition while assembling on nonmodified mica from the very dilute solutions. A scheme is proposed describing different stages of PBLG fibrogenesis on a charged surface. © 1998 John Wiley & Sons, Inc.