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The conditions necessary for synthesizing aragonite by the carbonation process were investigated. Aragonite formation was found to have no relation to the pH value, the mole ratio of MgCl 2 /Ca(OH) 2 , or the magnesium/calcium ion concentration in a solution. The synthesis of aragonite requires a concentration of magnesium ions in the appropriate range (ϳ0.1-0.26 mol/L) and a concentration of calcium ions below a certain range (less than ϳ0.16 -0.25 mol/L). An excess of calcium ions or magnesium ions favors calcite formation. Needlelike aragonite with a large aspect ratio was successfully synthesized in the present study.

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.

Summary: In this paper, we present the synthesis of a series of p‐type and n‐type semiconducting polyelectrolytes with triarylamine, oxadiazole, thiadiazole and triazine moieties. The synthesized polymeric hole and electron transport materials were examined optically and electrochemically using UV/Vis spectroscopy, PL spectroscopy and CV. Based on the optical and electrochemical data, each of the energy levels were calculated and all values suggested that they were promising hole‐ (p‐type) or electron‐transport (n‐type) materials for devices. Moreover, the synthesized ionic polymers were suitable for LBL thin film deposition from dilute polymer solutions and the multilayers were fully characterized by UV/Vis, PL spectroscopy and CV. magnified image

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