Polymer Journal
Vol. 40, No. 7 (July, 2008)

[Review Article] Web Release Date: May 14, 2008

577-589 Methodology for Homogeneous Dispersion of Single-walled Carbon Nanotubes by Physical Modification  T. Fujigaya and N. Nakashima [Full Text PDF(J-STAGE)]

We review the recent progress as well as our approaches to the solubilization of single-walled carbon nanorubes (SWNTs) based on physical modification. Especially, we focus on the ‘individual′ solubilization of pristine SWNTs in solvents. The individual solubilization based on physical modification can maintain SWNTs intact and is an attractive route for taking advantage of their intrinsic properties. Individually solubilized SWNTs are useful nanomaterials for a wide range of science and technology.

[Short Communication] Web Release Date: June 4, 2008

590-591 Rapid Synthesis of Phenolic Resins by Microwave-Assisted Self-Condensation of Hydroxybenzyl Alcohol Derivatives  A. Kobayashi and G. Konishi [Full Text PDF(J-STAGE)]

The microwave-assisted synthesis of phenolic resins by the polycondensation of hydroxybenzyl alcohol derivatives is described. The polymerization of 2-hydroxybenzyl alcohol in poly(ethylene glycol) using sulfuric acid as a catalyst under microwave irradiation (120 W) was completed within 5 min. The microwave irradiation enhanced the reaction rate of the polymerization and controlled the structures of the obtained novolacs; however, it did not influence the molecular weights, and the molecular weight distributions of the polymers.

[Regular Article] Web Release Date: May 14, 2008

592-600 Preparation and Characterization of pH and Temperature Dual Responsive-, Poly(N-isopropylacrylamide-co-itaconic acid) Hydrogels Using DMF and Water as Mixed Solvents  Y. Ling and M. Lu [Full Text PDF(J-STAGE)]

A series of Poly(N-isopropylacrylamide-co-itaconic acid) hydrogels were synthesized in the DMF and water mixed solvents. With the increase of the DMF content in the preparation, the degree of phase separation beomes pronounced. After purifiaction, macroporous hydrogels were formed. The chemical compositions of these hydrogels were almost the same, while with different polymer chain conformations. Those hydrogels with extended polymer chains and expanded network structures had superior performances in equlibrium swelling ratios and deswelling/reswelling experiments.

[Regular Article] Web Release Date: May 14, 2008

601-606 Improvement of the Performance of Transmission Holographic Grating by Hydrolysis-induced Change of the Property of Polymer Matrix  X. Wang, Y. H. Cho, and Y. Kawakami [Full Text PDF(J-STAGE)]

Methacrylate with silyl ether group was used as a reactive diluent together with multi-functional acrylate to fabricate transmission holographic polymer dispersed liquid crystal grating. Atmospheric moisture and cationic species generated from photo-initiator system could hydrolyze the silyl ether to afford hydrophilic hydroxyl groups to polymer matrix during grating formation. The change of the property of the matrix from hydrophobic to hydrophilic could efficiently induce phase separation of hydrophobic LC from the matrix. High diffraction efficiency and small angular selectivity were obtained even with low concentration of multi-functional acrylate.

[Regular Article] Web Release Date: May 14, 2008

607-613 Curing of Epoxy Resin by Hyperbranched Poly(amidoamine)-grafted Silica Nanoparticles and Their Properties  M. Ukaji, M. Takamura, K. Shirai, W. Gang, T. Yamauchi, and N. Tsubokawa [Full Text PDF(J-STAGE)]

Hyperbranched poly(amidoamine)-grafted silica nanoparticles having BF3-amine complex groups (Silica-PAMAM:BF3) have an ability to cure epoxy resin to give a novel epoxy resin/silica nanocomposite. The glass-transition temperature of the nanocomposite cured by Silica-PAMAM:BF3 was much higher than that by ethylene diamine in the presence of untreated silica. The glass-transition temperature of the nanocomposite increased with increasing content of hyperbranched PAMAM-grafted silica. It is expected that silica nanoparticles are incorporated uniformly with chemical bonds in the continuous epoxy resin network.

[Regular Article] Web Release Date: May 21, 2008

614-621 Conjugated Oligomers Containing Imidazole in Main Chain with Intramolecular Hydrogen Bonding  K. Takagi, K. Sugihara, J. Ohta, Y. Yuki, S. Matsuoka, and M. Suzuki [Full Text PDF(J-STAGE)]

Two kinds of conjugated oligomers containing benzimidazole or imidazole moieties were synthesized. The deprotection of phenolic hydroxyl groups caused red-shifts of UV and PL spectra. For a oligomer bearing the deprotected hydroxyl group, the increase of solvent polarity and the addition of base brought about the blue-shift of spectra, but the change from the solution to film state induced ignorable shifts. These findings support two intramolecular hydrogen bondings and a non-planar conformation in the conjugated oligomer.

[Regular Article] Web Release Date: May 14, 2008

622-628 Synthesis and Properties of Fluorine-Containing Poly(arylenemethylene)s as New Heat Resistant Denatured Phenolic Resins  T. Nemoto, G. Konishi, T. Arai, and T. Takata [Full Text PDF(J-STAGE)]

The synthesis of fluorine-containing poly(arylenemethylene)s as a new heat-resistant denatured phenolic resin is described. The fluorinated novolacs (2a) (Mn 8,200, Mw/Mn 2.1) was prepared by polymerization of 2,2-bis(4-methoxyphenyl)hexafluoropropane with formaldehyde. From the 1H NMR and 13C NMR spectra, the polymer had arylene-methylene units on the polymer backbone. The temperature at 10% loss in weight (T10) of 2a was found to be 425 °C. The thermal stability of poly(arylenemethylene)s was enhanced by the introduction of fluorine moieties in the polymer.

[Regular Article] Web Release Date: May 21, 2008

629-633 Facile Syntheses of Aromatic Polyesters Bearing Alicyclic Units in the Main Chains  K. Maeyama, K. Akiba, and H. Saito [Full Text PDF(J-STAGE)]

Interfacial polycondensation of cyclohexanedicarbonyl dichlorides and adamantanedicarbonyl dichloride with bisphenols 3a-e in 2 M NaOH aq./CHCl3 afforded semi-aromatic polyesters. Almost of the resulting polyesters 4 and 10 exhibit excellent thermal stability, solubility in organic solvents, and transparency.

[Regular Article] Web Release Date: May 21, 2008

634-639 Light Scattering and Phase Separation Studies on Cyclohexane Solutions of Six-Arm Star Polystyrene  Y. Tasaka, M. Okumoto, Y. Nakamura, and T. Norisuye [Full Text PDF(J-STAGE)]

Light scattering and phase separation experiments were carried out for four six-arm star polystyrene samples with different molecular weights in cyclohexane. Empirical equations for chemical potentials derived from the light scattering data allowed us to calculate the phase diagrams. The figure shows the observed and calculated binodals (unfilled circles and solid lines, respectively), spinodals (filled circles and dashed lines, respectively), and critical points (unfilled and filled triangles, respectively) for the sample molecular weights indicated.

[Regular Article] Web Release Date: May 28, 2008

640-644 Cationic Ring-Opening Copolymerization of O-Permethylcyclodextrin with Tetrahydrofuran  M. Suzuki and T. Shimazaki [Full Text PDF(J-STAGE)]

Cationic ring-opening copolymerizations of O-Permethylcyclodextrins (MeCDs) with tetrahydrofuran (THF) were studied. In THF that is the comonomer as well as the solvent, MeOTf as the initiator produced the copolymer consisting of tri-O-methylglucopyranose and tetramethylene ether units, while Et3O+PF6− mainly conducted the homopolymerization of THF. The addition of CH2Cl2 as the cosolvent favorably promoted the polymerization of MeCDs, producing the copolymer from both initiators. Interestingly, the initiator system of HI/I2 was found to chemoselectively polymerize MeCDs even in THF.

[Regular Article] Web Release Date: May 28, 2008

645-650 Direct Patterning of Poly(ether ether sulfone) Using a Cross-linker and a Photoacid Generator  K. Mizoguchi and M. Ueda [Full Text PDF(J-STAGE)]

A negative-type photosensitive poly(ether ether sulfone) (PSPEES) based on poly(oxybiphenyl-4,4′-diyloxy-1,4-phenylenesulfonyl-1,4-phenylene) (PEES), a novel cross-linker 4,4′-methylene-bis[2,6-bis(methoxymethyl)phenol] (MBMP) having good compatibility with PEES, and diphenylidonium 9,10-dimethoxyanthracene-2-sulfonate (DIAS) as a photoacid generator (PAG) has been developed. This excellent methodology using MBMP could be applicable for high peformance engineering plastics such as poly(phenylene ether), polycarbonate, and polythiophene as matrix polymers.

[Regular Article] Web Release Date: June 4, 2008

651-656 Synthesis and Properties of New Organosoluble Alkoxylated Naphthalene-Based Novolacs Preparaed by Addition-Condensation of Mono- or Di-alkoxynaphthalene with Formaldehyde  T. Nemoto and G. Konishi [Full Text PDF(J-STAGE)]

The preparation of new alkoxylated naphthalene-based novolacs by addition-condensation of methoxynaphthalene with formaldehyde is described. The polymerization of 2-methoxynaphthelene with an equimolar amount of formaldehyde proceeded to give 2 (Mn 3100, Mw/Mn 1.7) in good yield. The FT-IR, 1H and 13C NMR spectra suggest that 2 have naphthylene-methylene units and consist of approximately linear polymer backbones. From the TGA, T10 (the temperature at 10% loss in weight) value of 2 was 402 °C. The alkoxylated naphthalene-based novolacs have good thermal stability.

[Regular Article] Web Release Date: June 4, 2008

657-662 Recyclable Shape-memory and Mechanical Strength of Poly(lactic acid) Compounds Cross-linked by Thermo-reversible Diels-Alder Reaction  M. Yamashiro, K. Inoue, and M. Iji [Full Text PDF(J-STAGE)]

We developed poly(lactic acid) (PLA) compounds which achieved recyclable shape-memory and practical strength. The PLA compounds were cross-linked by the Diels-Alder cyclo-addition between furan and maleimide functions. The cross-linking condition was optimized to increase a reaction ratio between furan and maleimide functions, and the increase in the reaction ratio decreased the defects in its structure and enhanced its strength. Furthermore, using a flexible maleimide linker induced relaxation of the inner strain in the PLA compound also enhanced its strength.

[Regular Article] Web Release Date: June 4, 2008

663-666 Room Temperature Processable Organic-Inorganic Hybrid Photolithographic Materials Based on a Methoxysilane Cross-Linker  J. Y. Park and J.-B. Kim [Full Text PDF(J-STAGE)]

A novel organic-inorganic hybrid resist material containing a trimethoxysilane cross-linker was synthesized by copolymerization of 3-methacryloxypropyltrimethoxysilane and γ-butyrolactonyl methacrylate. This new resist system does not need the post-exposure baking step thereby eliminating the post-exposure delay problems. The initial lithographic evaluation of the resist showed the potential of the new platform for the next generation resist.