Effect of the state of the support surface on development of the Langmuir-Blodgett films based on poly(vinylidene fluoride)

For the deposition of poly(vinylidene fluoride) films via the Langmuir-Blodgett procedure, two methods of the surface treatment of the KRS-5 support were compared. In the first case, the surface was treated with water and, in the second case, with ethanol, In the latter case, the films composed of 30 monolayers were characterized by an increased continuity distortions in the film volume, and this fact was evidenced by spectroscopic measurements as a decrease in the effective concentration of polymer functional groups and by the specific morphological features of the films as observed in the polarized light. Analysis of the conformationally-sensitive absorption bands shows that the phase state of the formed crystals is also disturbed. The crystals of a ferroelectric beta-phase with a flat-zigzag conformation are characterized by the appearance of an increased number of conformational defects as bonds in TGTG(-) and T(3)GT(3)G(-) conformations. It was shown that a certain fraction of crystals crystallizes in a polymorphic gamma-modification. According to the advanced hypothesis, the optical heterogeneity of the film obtained by the second method is related to the development of microvoids during the expulsion of water clusters absorbed by the formed monolayer.