Amphotropic LC polymers and their multilayer buildup

Cationic and anionic LC ionomers, which possess both thermotropic and lyotropic phases, are suitable materials to fabricate multilayers with an internal structure. The LC ionomers were synthesized using a reactive precursor polymer and used for the multilayer buildup by solution-dipping and spin-coating methods based on the electrostatic attraction between polycations and polyanions. Multilayers prepared by the spin-coating method were thicker and showed a smoother surface than the ones prepared by the solution-dipping method. The multilayers prepared by the solution-dipping method showed, on the other hand, a better internal order with respect to layering and orientation of the mesogens, as a result of the liquid crystalline phase. The LC ionomers and multilayers thereof were fully characterized by NMR, UV, IR, DSC (differential scanning calorimetry), XRR (X-ray reflectometry), SPR (surface plasmon resonance), AFM (atomic force microscopy), and polarizing microscopy analyses.