Side-on liquid crystal polyacrylate in Langmuir–Blodgett films

Abstract

A side-on fixed liquid crystal polyacrylate has been investigated in Langmuir and Langmuir-Blodgett (LB) films. High in-plane orientation of the mesogenic groups has been observed within the LB multilayers, showing the ability of the LB technique to align a liquid crystal. The analysis of the in-plane order versus the dipping speed suggests some self-aggregation of the polymer in the monolayer. Within these aggregates, the molecular orientation (in-plane and out-plane) has been deduced from infrared dichroism experiments; the mesogenic group lies mainly parallel to the dipping direction and relatively flat on the substrate. This alignment of the polymer is however partially lost with time, leading to materials with less in-plane anisotropy.