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Vol. 59, No. 11, November(2010)

Optically Active PMMA
Takehiro KAWAUCHI
Department of Environmental and Life Sciences, Toyohashi University of Technology

Macromolecular helicity leads to optical activity (right-handed or left-handed helices) and is one of the most important basic structural motifs. Recently, we found that syndiotactic poly(methyl methacrylate) (st-PMMA), a stereoregular commodity polymer, folds into a one-handed helical conformation accompanied by gelation in toluene assisted by chiral alcohols as the gelling medium. Surprisingly, the st-PMMA helix is retained after complete removal of the chiral alcohols. Moreover, the optically active st-PMMA helix can further serve as the template to form an optically active st-PMMA/fullerene inclusion complex or st-/isotactic PMMAs stereocomplex. These unique supramolecular helical complexes offer potentially useful chiral materials as well as optoelectronic materials. Polymer Preprints, Japan 2010, 59, 98.

Synthesis of Supramolecular Solid Polymer Electrolytes via Self-assembly of a Diborylated Ionic Liquid
Noriyoshi MATSUMI, Akihito KAGATA, and Keigo AOI
Graduate School of Bioagricultural Sciences, Nagoya University
Novel supramolecular solid polymer electrolytes were prepared by self-assembly of a diborylated ionic liquid in the presence of bifunctional ligands. The polymers obtained were well soluble in common organic solvents such as methanol, and their structures were determined by 1H and 11B-NMR spectra. The ionic conductivity of the polymers was evaluated by the ac-impedance method after samples were dried thoroughly. The ionic conductivity observed was 8.8 ｴ 10ﾐ6 to 5.4 ｴ 10ﾐ6 Scmﾐ1 at 51淸 in the presence of an equimolar amount of LiTFSA [lithium bis(trifluoromethylsulfonyl) amide] per ionic liquid unit. The temperature dependence of the ionic conductivity was successfully fitted to VFT (Vogel-Fulcher-Tammann) plots, indicating that ionic conduction is taking place according to a typical ion transport model in viscous matrix. J. Power Sources, 2010, 195, 6182.

Toward Creation of Synthetic Viral Capsids
Kazunori MATSUURA
Department of Applied Chemistry, Kyushu University
In biological systems, various nano-assemblies are formed by self-assembly of proteins with highly symmetric ternary structures. For example, the dodecahedral internal skeleton of tomato bushy stunt virus (TBSV) self-assembles from C3-symmetric b-sheet subunits. Inspired by such self-assembly processes, we have developed a novel strategy for the construction of spherical assemblies consisting of C3-symmetric biomolecules such as DNA, b-sheet-forming peptides, and glutathione. Recently, we have found that synthesized viral b-annulus peptide (24 residues), which participates in the formation of the dodecahedral internal skeleton of TBSV, self-assembled into a nanocapsule with the size of 40ﾐ50 nm. The present findings would not only help to study mechanism of self-assembly of natural viral capsids, but also open a field of innovation in nanotechnology applying viral capsids. Polymer Preprints, Japan 2010, 59, 116.

Smart PEGylated Nanogels for Pinpoint Nano-Imaging
Motoi OISHI
Graduate School of Pure and Applied Sciences, University of Tsukuba
Stimuli-responsive PEGylated nanogels (diameter < 100 nm) constructed from tethered PEG chains and a polyamine gel core containing 19F-compounds or gold nanoparticles (GNPs: diameter < 10nm) were successfully prepared. In particular, the PEGylated nanogels containing 19F- compounds showed remarkable on-off regulation of 19F MRIs (magnetic resonance images) in response to the extracellular pH (=6.5) of tumor environment, due to change in the T2 value of the 19F-compounds through the volume phase transition of the polyamine gel core. Additionally, the PEGylated nanogels with large payload of the GNPs in a single core showed a high contrast X-ray CT (computed tomography)-image, owing to the high X-ray absorption character of the GNP. These facts suggest that smart PEGylated nanogels can be useful as a tool for pinpoint nano-imaging. Polymer Preprints, Japan 2010, 59, 119.

Dynamic Covalent Approach to Macromolecular Design of Reactive Polymers
Hideyuki OTSUKA
Institute for Materials Chemistry and Engineering, Kyushu University
Programmed formation of asymmetrical (miktoarm) star-like nanogels by cross-linking reaction of well-defined di-block copolymers with complementarily reactive alkoxyamine units in the side chains was accomplished. Several types of di-block copolymers with alkoxyamine units connected at different positions and different chemical compositions were prepared by copolymerization of methyl methacrylate and methacrylic esters with alkoxyamine from poly(methyl methacrylate) or polystyrene prepolymers using the atom transfer radical polymerization method. Miktoarm star-like nanogels were formed by dynamic covalent exchange among alkoxyamine units when heating a mixture of two different types of di-block copolymers in anisole. Furthermore, structural transformation from the star-like nanogels to linear polymers was demonstrated by dynamic covalent exchange among alkoxyamine units in the star-like nanogels and excess added alkoxyamine compounds. Polymer Preprints, Japan 2010, 59, 110., Macromolecules 2010, 43, 1785.

Interaction between Polymer Surface and Electrodeposited Inorganic Oxides
Mitsuru WATANABE
Osaka Municipal Technical Research Institute
Electrodeposition of inorganic oxides (ZnO, CeO2, and TiO2) was conducted on a modified electrode. The electrodeposition on a polymer nanoparticle adsorbed electrode resulted in polymer-core/metal oxides-shell nanostructures. These characteristic structures were attributed to the metal oxides nucleation site selectivity derived from the specific interaction between sulfate groups on the polymer particle surface and metal ions. In the case of ZnO, ZnO crystals grew perpendicularly from the surface of the polymer particles. This orientation selective growth of ZnO crystals was also due to the same interaction, which favors the (001) face being attached onto the polymer surface. Encouraged by this fact, polystyrenesulfonate was immobilized on an electrode, and ZnO was deposited on the modified electrode. As a result, c-axis selective deposition of ZnO crystals was achieved without using a heteroepitaxial growth technique. Polymer Preprints, Japan 2010, 59, 92.

Development of Polytetramethylglycolide from Lactic Acid for Sustainable Biomass-Based Polyester
Yoshito ANDOU1, Yoshihito SHIRAI1,2, and Haruo NISHIDA1
1Eco-Town Collaborative R&D Center for the Environment and Recycling, Kyushu Institute of Technology.
2Department of Biological Functions and Engineering, Kyushu Institute of Technology
Poly(L-lactide)(PLLA), which is a well-known biomass-based polyester, has been attracting considerable interest from both fundamental and practical perspectives because it is an excellent recyclable polymer based on its complete depolymerization property. However, PLLA has some problems such as hydrolyzability and racemization at high temperatures, which causes often lowering in crystallinity and heat-resistance. In order to solve these problems of PLLA, we focused on a racemization-free polymer, polytetramethylglycolide (PTMG). Now, we have confirmed that acyclic monomer, a- hydroxyisobutyric acid (HIBA), is prepared from L/D-lactic acid by substituting the active a-hydrogen with a methyl group, HIBA is converted into tetramethyl glycolide, resulting in preparation of PTMG by a ring-opening polymerization. PTMG showed excellent thermal properties, hydrolysis-resistance, and recyclability compared with PLLA. Polymer Preprints, Japan 2010, 59, 2059.

Encapsulation of Liquid Droplets with Hydrophobic Polymer Micro-particles
Daisuke MATSUKUMA, Hirohmi WATANABE, and Atsushi TAKAHARA
JST, ERATO, Takahara Soft Interfaces Project
Liquid marbles are formed by the encapsulation of a liquid droplet with hydrophobic particles. Because liquid marbles combine the characteristics of both liquid and solid, they behave like soft solids, and exhibit unique properties such as the ability to float on a water surface. We have recently found that poly[2-(perfluorooctyl)ethyl acrylate] (PFA-C8) micro-particles, which are highly crystalline and have a low surface energy, are useful for the encapsulating of various liquid droplets. The order of the fluoroalkyl side chains of the micro-particles remained as high as that in a PFA-C8 bulk polymer, as confirmed by X-ray diffraction. The orientation of the fluoroalkyl groups at the surface results in a low surface energy of the micro-particles, which is indispensable for the fabrication of stable liquid marble. This result should be helpful for an improved physicochemical analysis of liquid marble and for the development of novel applications. Polymer Preprints, Japan 2010, 59, 1196.

Study on Life Cycle Inventory (LCI) Data of Commodity Resins
Hajime NISHIHARA
Technology Research & Development Department, Plastic Waste Management Institute
We have conducted a survey of life cycle inventory (LCI) data on 8 commodity resins (LDPE, HDPE, PP, PS, EPS, PET, PVC, PMMA), ranging from the mining of natural resources to the resin production. The LCI data consisted of crude oil mining, transportation, oil refining, power plants (non-utility power generation and other purposes), utility power generation, and resin production data. The LCI data were collected in cooperation with various resin industry associations, and processed with a horizontal averaging method, which treated all responses of individual processes based on a present approach and calculated a weighted average value and used this value as common physical-unit data for all processes subsequent to it. The results are as follows. Polymer Preprints, Japan 2010, 59, 2035.