Polymer Journal
Vol. 41, No. 1 (January, 2009)


[Review Article] Web Release Date: August 12, 2008
1-15 Novel Synthesis of Polymers with Well-Defined Structures Based on Selective Reaction of Cyclic Sulfides and Cyclic Ethers Catalyzed by Quaternary Onium Salts
 A. Kameyama and T. Nishikubo
[Full Text PDF(J-STAGE)]
Novel syntheses of polymers with well-defined structures were developed based on the selective reactions of thiiranes and oxiranes with carboxylic esters catalyzed quaternary onium salts. Polymers with pendant chloromethyl groups were synthesized by polyaddition of difunctional thiiranes or oxiranes. Acyl-transfer polymerization of thiiranes was successfully developed. Alternating ring-opening polymerizations of oxiranes with γ-thiobutyrolactone, or of oxetane with cyclic carboxylic anhydrides were also developed. Sequence-ordered polymers were synthesized by transformation of polymer backbones of poly(S-thioester).

[Short Communication] Web Release Date: November 12, 2008
16-17 Living Cationic Polymerization of Vinyl Ethers Using a Strong Lewis Acid without Stabilizing Additives: Effective Interaction of Monomers with Growing Ends and/or SnCl4
 M. Yonezumi, S. Kanaoka, S. Okumoto, and S. Aoshima
[Full Text PDF(J-STAGE)]
[Supporting Information]
Cationic polymerization was examined with a strong Lewis acid in the absence of external additives, which stabilize carbocations and Lewis acids. Surprisingly, at −30 °C, SnCl4 induced living polymerization of isobutyl vinyl ether in toluene (Mw/Mn∼ 1.1). On the other hand, no living nature was observed with other Lewis acids even at −78 °C. Both experimental results and computational chemistry suggested that a vinyl ether monomer stabilized a carbocation and a Lewis acid to realize living polymerization.

[Short Communication] Web Release Date: November 27, 2008
18-19 Structural Study of Silk-like Peptides Modified by the Addition of the Cell Adhesive Sequence, RGD, Using 13C CP/MAS NMR
 C. Tanaka, A. Asano, T. Kurotsu, and T. Asakura
[Full Text PDF(J-STAGE)]
We synthesized the 13C-labeled peptides with the sequences (AAG)n1 or (AG)n2 in both N- and C-terminal parts and the cell-adhesive sequence, ASTGRGDSPAAS in the central part in order to obtain basic information to design the cell-adhesive silk-like proteins. The 13C CP/MAS NMR was used to characterize these structures in the solid states. One of the possible structures was shown.

[Regular Article] Web Release Date: November 6, 2008
20-25 Fluorescent Hyperbranched Polyamine with s-Triazine: Synthesis, Characterization and Properties Evaluation
 S. S. Mahapatra and N. Karak
[Full Text PDF(J-STAGE)]
A hyperbranched polyamine with s-triazine unit has been synthesized. The fluorescence behavior of the polymer was investigated with respect to it′s nature of end groups, concentration, pH of the medium and presence of metal ion (Cu2+).

[Regular Article] Web Release Date: November 6, 2008
26-33 Reassessment of Free-Radical Polymerization Mechanism of Allyl Acetate Based on End-Group Determination of Resulting Oligomers by MALDI-TOF-MS Spectrometry
 A. Matsumoto, T. Kumagai, H. Aota, H. Kawasaki, and R. Arakawa
[Full Text PDF(J-STAGE)]
Allyl acetate (AAc) was polymerized radically and the resultant oligomeric poly(AAc)s were characterized using MALDI-TOF-MS spectrometry in order to reassess the classical AAc polymerization mechanism. The fate of resonance-stabilized monomeric allyl radical generated via monomer chain transfer of growing polymer radical was pursued in terms of the competition between the initiation of a new polymer chain and the chain stopping reaction of a growing polymer radical, respectively.

[Regular Article] Web Release Date: November 12, 2008
34-39 Preparation of Modified Low-Melting Point Polypropylene: Effect of Tacticity for Modification
 R. Aburatani, S. Machida, H. Nakashima, and T. Fujimura
[Full Text PDF(J-STAGE)]
Low-melting point polypropylene with middle range of isotacticity was modified with maleic anhydride and acrylate monomers. The degrees of modification depend on the tacticity of base polypropylene. Isotactic polypropylene is most difficult to modify. From the difference of the polypropylene characters, various reaction temperature and radical initiators could be applicable.

[Regular Article] Web Release Date: November 6, 2008
40-45 A Simple Preparation of C60-Poly(ethylene glycol) Gel and its Properties
 H. Wakai, T. Momoi, T. Yamauchi, and N. Tsubokawa
[Full Text PDF(J-STAGE)]
Poly(ethylene glycol) (PEG) biradicals formed by thermal decomposition of macroazo-initiator, (Azo-PEG)n, were successfully trapped by C60 fullerene to give C60-PEG gel containing C60 fullerene at cross-linked point. The reaction conditions to give highest gel fraction is summarized as follows: the feed molar ratio, 5 (mol/mol); concentration of C60, 3.5 mmol/L; 70 °C; 24 h. C60-PEG gel was swelled in water, methanol, and THF and degree of swelling were about 5.1 to 7.8. Breaking strength decreased with increasing the feed molar ratio.

[Regular Article] Web Release Date: November 6, 2008
46-50 The Synthesis of Complex Polymer Electrolytes Based on Alginic Acid and Poly(1-vinylimidazole) and Application in Tyrosinase Immobilization
 M. Kartal, S. K. Kayahan, A. Bozkurt, and L. Toppare
[Full Text PDF(J-STAGE)]
Complex polymer electrolyte networks consisting of alginic acid, AA and poly 1-vinylimidazole, PVI were prepared by mixing the polymers at several stoichiometric ratios. The materials were characterized by FT-IR and elemental analysis, EA. Enzyme entrapped polymer networks (EEPN) were produced by immobilization of tyrosinase in the matrix during complexation. The maximum reaction rate Vmax, Michaelis-Menten constant Km, the temperature and pH optimizations, as well as operational stability and shelf life of the immobilized enzyme were investigated.

[Regular Article] Web Release Date: November 12, 2008
51-57 Study on Mechanical, Thermal and Electrical Characterizations of Nano-SiC/Epoxy Composites
 T. Zhou, X. Wang, M. Gu, and D. Xiong
[Full Text PDF(J-STAGE)]
The effect of nano-SiC particles on mechanical, thermal and electrical properties of epoxy was studied by lap shear, TGA, DSC and electrical tests. The results showed that the addition of nano-SiC particles remarkably improves shear strength, dielectric constant and loss tangent, while slightly enhances thermal stability of epoxy. 8 vol. % silane treated nano-SiC/epoxy composite has the highest shear strength, good temperature independence of dielectric properties and enough volume resistivity, which meet the demand of some microelectronics materials.

[Regular Article] Web Release Date: November 12, 2008
58-62 Effects of Chain Ends and Three-Segment Interactions on Second and Third Virial Coefficients of Four-Arm Star Polystyrenes
 Y. Nishi, Y. Nakamura, and T. Norisuye
[Full Text PDF(J-STAGE)]
Second and third virial coefficients (A2 and A3, respectively) for cyclohexane solutions (34.5 °C) of four-arm star polystyrene (4SPS) samples with a benzyl group at each arm end (4SPS-Bz) and 4SPS samples with a sec-butyl group at each arm end (4SPS-Bu) were determined as functions of weight-average molecular weight Mw. The negative A2 for 4SPS-Bz (unfilled squares) reflects the effects of three-segment interactions, while the positive A2 for 4SPS-Bu (filled squares) is due to the effects from arm ends.

[Regular Article] Web Release Date: November 12, 2008
63-68 Biphasic Polycondensation of 4-Bromo-2,6-dimethylphenol Using Silica Gel as a Promoter
 Y. Shibasaki, M. Takahashi, M. Tanaka, J. N. Kondo, and Y. Oishi
[Full Text PDF(J-STAGE)]
Poly(2,6-dimethyl-1,4-phenylene ether) (PPE) was successfully prepared by the biphasic polymerization of 4-bromo-2,6-dimethylphenol (BDMP) using silica gel as a promoter under air. Silica gel was alkaline hydrolyzed to afford water soluble siloxane oligomers, which acted as an effective phase transfer agent for the polymerization of BDMP. The pure PPE was easily separated by the ordinal reprecipitation process from the siloxane oligomers, which were then retransformed into silica gel by the condensation of the silanol groups in acidic medium.

[Regular Article] Web Release Date: November 19, 2008
69-73 Synthesis and Characterizations of Graft Copolymer of Ethylcellulose with Poly(caprolactone monoacrylate)
 D. Wang, C. Chen, Y. Xuan, Y. Huang, and J. Shen
[Full Text PDF(J-STAGE)]
Ethylcellulose grafting polycaprolactone monoacrylate copolymer (EC-g-PCLA) was synthesized by a two-step reaction of ethylcellulose (EC) with poly(caprolactone monoacrylate) (PCLA). The flow temperature of graft copolymer was lower than that of the pure EC and decreased with increasing the grafting percentage. Outdoor soil burial and active sludge tests indicated that the graft copolymer has biodegradability in natural conditions.

[Regular Article] Web Release Date: November 19, 2008
74-82 Mechanical and Thermal Properties of a Hot-melt Adhesive of Tribrock Copolymer Added with a Miscible Homopolymer
 H. Kondo and A. Toda
[Full Text PDF(J-STAGE)]
Adhesives made of a styrenic triblock copolymer with different content of a miscible homopolymer, PPE, have been examined by various methods. With SAFT and 180° peel test, the thermal resistance of adhesive performance was examined. By DMA and T-M DSC, the glass transition temperature of the styrene domainm, Tg(StD), was examined. It has been confirmed that the thermal resistance depends on Tg(StD), which linearly increases with the added content of PPE in styrene domains.

[Regular Article] Web Release Date: November 19, 2008
83-89 Transport Coefficients of Poly(diisopropyl fumarate) in Dilute Solution
 M. Nakatsuji, K. Soutoku, M. Osa, and T. Yoshizaki
[Full Text PDF(J-STAGE)]
The ratio Φ (Flory–Fox factor) of the hydrodynamic molar volume to the 3/2 power of the mean-square radius of gyration ‹ S2› and also the ratio ρ−1 of the hydrodynamic radius to ‹ S2›1/2 of the poly(diisopropyl fumarate) in tetrahydrofuran at 30.0 °C (○) are found to lie between those for atactic polystyrene (△) and poly(n-hexyl isocyanate) (□).

[Note] Web Release Date: November 6, 2008
90-93 Macroporous Silicagel Substrate for Stereoregular Template Polymerization of Methacrylic Acid Using Stereocomplex Assembled Thin Films
 H. Ajiro, D. Kamei, and M. Akashi
[Full Text PDF(J-STAGE)]
[Supporting Information]
Macroporous silicagel (diameter: 7 μm, pore: 100 nm) was selected as a suitable substrate for the stereoregular template polymerization of methacrylic acid (MA) in the presence of isotactic poly(methyl methacrylate) (it-PMMA). A stereocomplex of it-PMMA and syndiotactic poly(methacrylic acid) (st-PMAA) was formed using Layer-by-layer assembly on macroporous silicagel. The subsequent extraction of the st-PMAA provided a porous it-PMMA thin film as a stereoregular, radical polymerization field for MA, and the reproducibility of this syndiospecific polymerization was confirmed.