Effects of Microphase Separation and Density–Density Correlations in Amorphous Polymer Films

Abstract

The topology of density fluctuations on the surfaces of amorphous thin films prepared from solutions of some flexible-chain polymers has been studied based on electron microscopy data on submicron and micron scales. It is shown that the microphase-separation effects in the films become stronger with an increase in the initial solution concentrations due to self-organization of macromolecular aggregates (clusters): anisotropy, long-range order, and correlation length ξ of density fluctuations increase. The self-organization is completed with formation of an infinite cluster of particles with a periodically inhomogeneous density, which occupies ~30% of the film surface. The density–density correlation function of this cluster on the ~ξ scale is universal and independent of the polymer composition and molecular weight.