Preparation and characterization of monolayers and multilayers of preformed polymers

Abstract

In an attempt to study which factors determine the transferability of monolayers of preformed polymers from the air-water interface onto substrates we investigated flexible polymers (poly(octadecylmethacrylates) (PODMAs)) and 0t-helical polymers (polyglutamates). Pressure-area isotherms show the formation of a liquid-analogous state which depends on temperature and side chain "impurity". Ymode Langmuir-Blodgett multilayers of these polymers can be formed with a constant transfer ratio under conditions at which a more or less liquid-analogous state exists. Polarized IR spectra suggest that the polyglutamate a helices in the multilayer are oriented with the main axis parallel to the transfer direction and that carbon Side chains are practically randomly oriented around the a-helical cylinder. In PODMA multilayers the side chains are perpendicular to the film. In both cases the sidechains seem to interdigitate.

Mixed mono- and multilayers of poly(isocyanide)s with non-linear optically active side chains

“…Two general types have been successfully used for the preparation of LB films: comb-like polymers which resemble low molecular weight amphiphiles [1][2][3][4] and rigid rod polymers [5][6][7][8]. Recently, a number of studies have appeared dealing with polymeric non-linear optical (NLO) materials.…”

Structure of poly(γ-benzyl-L-glutamate) monolayers at the gas–water interface: A Brewster angle microscopy and x-ray scattering study

“…In recent years, various ␣-helical poly͑L-glutamates͒ have been studied both as LMs on water 23,25,26,[34][35][36][37] and as LB films on solid substrates. 26,34,[37][38][39][40][41][42][43][44][45][46][47][48][49] In most of these studies the primary objective has been to achieve good-quality LB films that possess technologically important properties, 50 such as lateral homogeneity, 23,45 thermal 37,44,47,49 and mechanical 45,48 stability, low defect density, 38,45 and optical anisotropy; 38,39,42 in addition, potential applications, 50,51 for example, as optical wave guides, 38,41,42 optical data storage media, 43,44 and photoresists, 37 have also been suggested. However, despite the high activity in this research area, direct structural characterizations at the intermolecular level have been limited mostly to transferred LB films, as opposed to their LM counterparts, partly due to experimental difficulties invol...…”

Preparation and Characterization of Poly(N-1H,1H- pentadecafluorooctylmethacrylamide) Langmuir-Blodgett Film

“…[5][6][7] For the fabrication of polymeric LB films, comb-like polymers with well-defined hydrophilic groups and hydrophobic hydrocarbon side chains are mostly studied. [8][9][10][11][12][13][14] Monolayer formation and LB film preparation in these polymers are determined by the balance of hydrophilic and hydrophobic interactions.Langmuir-Blodgett films of comb-like polymers with fluorocarbon side chains are attracting much recent attention due to their characteristic properties such as low friction, excellent insulation, excellent durability, and so on. 15,16 The fluorocarbon chains are also hydrophobic and have rigid character (stiffness of the C-F bond), which are suitable factors for stable monolayer formation.…”

“…[5][6][7] For the fabrication of polymeric LB films, comb-like polymers with well-defined hydrophilic groups and hydrophobic hydrocarbon side chains are mostly studied. [8][9][10][11][12][13][14] Monolayer formation and LB film preparation in these polymers are determined by the balance of hydrophilic and hydrophobic interactions.…”