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Vol. 61, No. 8, August (2012)

Functional Molecular Systems Based on Self-Assembly
Nobuo KIMIZUKA
Graduate School of Engineering, Center for Molecular Systems, Kyushu University

The ability to self-assemble coordination nanoarchitectures holds promise to tailor and improve their functions for technologically important applications. We developed supramolecular covering techniques to convert solid-state one- dimensional coordination compounds into lipophilic, soluble nanowires. They show unique characteristics such as thermochromism, solvatochromism and spin conversion in organic media, which are controlled based on self-assembly. Macroscopic orientation of these coordination molecular wires can also be controlled by using electrophoretic orientation techniques, as recently demonstrated for lyotropic liquid crystals of halogen-bridged diruthenium complexes in decane. Self-assembly of coordination networks has been also demonstrated in aqueous environments. Upon mixing nucleotides and lanthanide ions in water, amorphous coordination nanoparticles are spontaneously formed. These coordination networks revealed adaptive inclusion of functional molecules such as dyes, porphyrins and even inorganic nanoparticles. These unique features provide opportunities to design functional molecular systems.
Polymer Preprints, Japan 2012, 61, 47.

Development of Low Isotactic Polyolefin
Yutaka MINAMI
Performance Materials Laboratories, Idemitsu Kosan Co., Ltd.
Polymeric materials development has made great progress by the innovation of catalyst technology for polymerization. In recent years, polyolefins were expected to be used for various applications as substitutions for other materials such as metal, paper and wood. Metallocene catalysts are a key technology to produce high performance polyolefins designed specifically for each application. We report novel polypropylene (LMPP) with low isotacticity and high molecular weight, which is synthesized using specific C2-symmetric doubly bridged metallocene complexes. LMPP has some isotactic sequences in stereorandom order and its tacticity can be precisely controlled as designing the metallocene catalysts. LMPP is provided by pellets and applicable to hot melt adhesive, elastic fiber, nonwoven fabric and so on due to its unique elastomeric property and excellent compatibility with isotactic polypropylene.
Polymer Preprints, Japan 2012, 61, 25.
Kobunshi 2010, 59, 853.

Unique Thermodynamics of POSS Ionic Liquids
Kazuo TANAKA* and Yoshiki CHUJO
Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University
Three-dimensional polymeric materials have gathered attention due to their unique structural features. The room temperature-ionic liquids (ILs) which possess the melting temperature below 25 ℃ were obtained by using octacarboxylate-presenting polyhedral oligomeric silsesquioxane (POSS) as a polyanion. It was found that the connection of ion pairs to POSS can significantly improve the thermal stability and decrease the melting temperatures of the ion pairs. In particular, only the modified POSS with larger number of ion pairs can be a thermally-stable room temperature-IL. Finally, from the series of thermodynamic and conformational analysis, it was revealed that the highly-symmetrical distribution of ion pairs, originating from the cubic framework of POSS, is essential to explain the characteristic changes in thermal properties of ion pairs connected to POSS.
J. Am. Chem. Soc., 2010, 132, 17649.
Polymer Journal, 2011, 43, 708.