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Vol. 61, No. 3, March (2012)

Preparation of biomimetic membrane for reverse osmosis process using supported lipid bilayer
Hideto MATSUYAMA
Center for Membrane and Film Technology, Kobe University

Seawater desalination by a membrane process has been operated using polymeric membranes in commercial scale. Recently, biomimetic membranes for practical application are receiving much attention as one new type of innovative materials. In biological membranes, transportation of water and ions is mainly carried out by water channels. Thus, the biological membrane showed superior water permeability and selectivity compared with the polymeric membranes. However, water transport through biological membranes is usually driven by osmotic pressure rather hydraulic pressure. This work reports about the feasibility of adopting biomimetic membranes for water transport driven by hydraulic pressure. We prepared a supported lipid bilayer (SLB) on the NF membrane and incorporated a water channel into the SLB by self-assembling of amphotericin B (AmB) and ergosterol. The introduction of water channels in the lipid layer was quite useful to obtain higher water permeability and NaCl rejection.
Polymer Preprints, Japan 2011, 60, 10.

Highly stable polymeric micelles
Yuichi OHYA
Faculty of Chemistry, Materials and Bioengineering, Kansai University
Polyanion-coated biodegradable polymeric micelles were prepared by coating a positively charged polymeric micelle consisting of poly(L-lysine)-block-poly(L-lactide) (PLys-b-PLLA) AB diblock copolymers with anionic hyaluronic acid (HA) by polyion complex (PIC) formation. The obtained HA-coated micelle showed significantly high colloidal stability and extremely low critical aggregation concentration in aqueous solution. HA is recognized by a liver sinusoidal endothelial cell (LSEC). Specific interaction of HA-coated micelle with LSECs was investigated. Although control micelles coated with heparin or carboxymethyl-dextran were incorporated into both of Kupffer cells and LSECs, the HA-coated micelle was taken up into only LSECs. The results suggest the HA-coated micelle has a potential utility as drug delivery vehicles exhibiting high stability and specific accumulation into LSECs.
Polymer Preprints, Japan 2011, 60, 40.
J. Contr. Rel. 2011, 155, 104.

Synthesis of Novel Macrocyclic Hosts ﾒPillar[5]areneﾓ and Their Application for Supramolecular Materials
Tomoki OGOSHI
Department of Chemistry and Chemical Engineering, Graduate School of Natural Science and Technology, Kanazawa University
In 2008, we reported a new class of macrocyclic hosts and named it ﾒPillar[5]arenesﾓ. Pillar[5]arenes combine the advantages and aspects of traditional hosts and have a composition similar to those of typical calix[n]arenes. Pillar[5]arenes have repeating units connected by methylene bridges at the para-position, and thus show a unique symmetrical pillar architecture differing from the basket-shaped structure of meta-bridged calix[n]arenes. Pillar[5]arenes show high functionality similar to cyclodextrins. Pillar[5]arenes form inclusion complexes with electron accepting guests, and the host-guest properties of pillar[5]arene are analogous to those of cucurbit[n]urils. Pillar[5]arenes can be used as building blocks for the construction of supramolecular architectures such as rotaxanes, polyrotaxanes and nanotubes. Planar chirality and mono-functionality are original features of pillar[5]arenes.
J. Am. Chem. Soc. 2008, 130, 5022.
Polymer Preprints, Japan 2011, 60, 111.

In-plane Orientation in Colorless Polyimides as Induced by Solution Casting from Polyimide Varnishes (6). Applications to Low-CTE and Transparent Plastic Substrates
Tomohiro ISHIGAMI, Junichi ISHII, and Masatoshi HASEGAWA
Faculty of Science, Toho University
We developed a novel colorless aromatic polyimide (PI) system possessing a low linear coefficient of thermal expansion (CTE), which is attributed to spontaneous in-plane chain orientation induced by simply coating/drying a stable cyclopentanone solution of the PI without thermal imidization processes. The backbone structure of the PI is shown in Fig. 1. A high quality of the PI films can be formed using a variety of solvents owing to excellent solubility of the chemically imidized sample. The colorless PI cast film achieved excellent combined properties: a high Tg of 328 淸, a very low CTE of 9.9 ppm/K, sufficient flexibility (elongation at break eb= 27%). Accordingly, the present PI system can be applied as plastic substrates in flat panel displays such as electronic paper displays.
Polymer Preprints, Japan 2011, 60, 1137.

Expansion of Ia3d Cubic Lattice under Pressure
Yoji MAEDA1, Shoichi KUTSUMIZU2, and Shinichi SAKURAI3
1Department of Life Science and Sustainable Chemistry, Tokyo Polytechnic University
3Department of Chemistry, Gifu University
3Graduate School of Science and Engineering, Kyoto Institute of Technology
1,2-Bis(4ﾕ-n-alkoxybenzoyl)hydrazine BABH-n is a soft material that shows two types of thermotropic cubic phases (Ia3d and Im3m), of which the former consists of two pairs of 3-by-3 interpenetrating networks (gyroid). The Ia3d cubic lattice of BABH-12 expands slightly by 4% under pressure (~25 MPa), while the Ia3d lattices of BABH-16 and -18 expand continuously with increasing pressure both by ~22% at 100 and 125 MPa, respectively. The cubic phase of BABH-14 takes the Im3m type structure, which is less stable and transformed into Ia3d type under pressure. The origin of the Ia3d cubic lattice expansion is ascribed to the change in volume ratio between the flexible alkyl chain and the effective core, i.e., extension of the flexible chain and shortening of the effective core (Type II to Type I).
Polymer Preprints, Japan 2011, 60, 754.

Multi-Colored Dye Sensitization of Polymer/Fullerene Solar Cells
Hideo OHKITA1,2, Satoshi HONDA1, Hiroaki BENTEN1, and Shinzaburo ITO1
1Graduate School of Engineering, Kyoto University
2Japan Science and Technology Agency, PRESTO
We have demonstrated that the light-harvesting wavelength region of polymer solar cells can be easily expanded by incorporating various dye molecules that have complementary absorption bands in the near-IR region. In a quaternary blend solar cell consisting of poly(3-hexylthiophene) (P3HT), a fullerene derivative (PCBM), a silicon phthalocyanine (SiPc), and a silicon naphthalocyanine (SiNc), the short-circuit current (JSC) increased by 20% from 8.96 to 10.9 mA cmﾐ2 because of the expanded absorption in the near-IR region, and hence the power conversion efficiency (PCE) was also improved by 20% from 3.5 to 4.3%, compared to those of the control P3HT/PCBM solar cell without dye. We believe that this is a simple and versatile approach to expand the light-harvesting wavelength region and therefore can be an alternative to tandem solar cells.
Polymer Preprints, Japan 2011, 60, 1212.