POLYMERIZABLE LYOTROPIC LIQUID-CRYSTALS CONTAINING TRANSITION-METAL IONS AS BUILDING-BLOCKS FOR NANOSTRUCTURED POLYMERS AND COMPOSITES

Transition-metal-containing analogues of a polymerizable lyotropic liq uid crystal were prepared from sodium p-styryloctadecanoate by ion exc hange with water-soluble metal chlorides, nitrates, and acetates. The mesophases of these amphiphilic monomers were investigated by polarize d light microscopy, low-angle X-ray diffraction, and infrared spectros copy. It was found that cadmium(II), manganese(II), and cobalt(II) p-s tyryloctadecanoate form an inverted hexagonal lyotropic phase at ambie nt temperature (22 degrees C), while the copper(II) salt forms a colum nar hexagonal thermotropic phase. The monomers can be cross-linked pho tolytically in their respective liquid crystal phases with retention o f phase architecture to yield polymer networks containing ordered micr odomains of transition-metal ions. The relationship between the dimens ions of the hexagonal mesophase formed and the identity of the counter ion present in each salt is discussed. The polymerized inverted hexago nal phase of the cadmium salt was also used as a template for the form ation of CdS nanoparticles, affording a novel, nanostructured composit e.