Langmuir-Blodgett mono- and multilayers of (di)alkoxy-substituted poly(p-phenylenevinylene) precursor polymers.: 2.: Stability, transfer, and multilayer structure of (di)alkoxy-substituted precursor PPVs

The Langmuir monolayer stability and transfer properties of (di)alkoxy-substituted precursor PPVs were studied. All polymers formed stable monolayers, but the packing of the monomeric units in the monolayer depended strongly on the substituents. The less closely packed monolayers can be transferred with the Langmuir-Blodgett technique, while the closely packed monolayers, with strong pi-pi interaction between the aromatic rings, can only be transferred with the Langmuir-Schaefer technique due to the stiffness of the monolayers. Transmission and grazing incidence reflection FT-IR spectroscopy in combination with IR spectra computer simulations revealed that in many instances the orientation of the precursor at the water interface is largely preserved after transfer of the monolayer. The roughness and the thickness of the multilayers were determined by small-angle X-ray reflection.