Chapter 1 - Langmuir-Blodgett and Self-Assembled Polymeric Films

Abstract

This chapter deals with the Langmuir–Blodgett and self-assembled polymeric films. The growing interest in organic materials requires research that can be broadly divided into four main categories—namely, (1) material design, (2) synthesis, (3) processing and characterization, and (4) testing for applications. Having the designed material synthesized, in most cases an important step prior to testing a proposed application is the processing of the materials into a desired form, preferably in the form of ultrathin films that often possess a large surface area. For organic materials, in particular, the most commonly used techniques are simple drop casting, spin casting, dip coating, Langmuir–Blodgett technique, and self-assembly. A common feature in all these techniques is that the material of interest is first dissolved in a suitable solvent, being subsequently either physisorbed or chemisorbed onto a surface. The Langmuir–Blodgett and the self-assembly methods are looked upon as viable means of producing ultrathin films with controllable film thickness and molecular packing. While the former technique involves the formation of a monolayer film at the air-water interface and subsequent transfer as a multilayer film onto a solid substrate, the latter technique is essentially based on the ionic interaction between alternate layers.