Polymer Journal
Vol. 39, No. 4 (April, 2007)

[Award Accounts: SPSJ Hitachi Chemical Award (2006)] Web Release Date: March 12, 2007

277-293 Optoelectronic Properties and Nanostructure Formation of σ-Conjugated Polymers  S. Seki and S. Tagawa [Full Text PDF(J-STAGE)]

This paper reviews recent studies on the opto-electronic properties of σ-conjugated polymers as well as the nanostructure formation based on the polymeric materials by the single particle nanofabrication technique (SPNT). The intra-chain delocalization and mobility of charge carriers along their backbones are quantitatively discussed by transient absorption spectroscopy and time-resolved microwave conductivity measurements using several radiation sources which are also applied to produce clear 1-D nanowires based on the polymers by SPNT.

[Short Communication] Web Release Date: February 26, 2007

294-295 Biosynthesis and Characterization of the Artificial Protein Consisting of Marine Mussel Adhesive Protein and Silk-Like Protein Sequences  S. Hatae, T. Asakura, and Y. Fukushima [Full Text PDF(J-STAGE)]

This study describes biosynthesis and characterization of novel adhesive material consisting of mussel adhesion protein and silk fibroin repetitive sequences. The novel adhesive protein with high β-structure content was synthesized by genetically engineered technique and had good adhesive ability on organic substrates.

[Short Communication] Web Release Date: February 26, 2007

296-297 A New Technique to Study Kinetics of Chain Conformation in Polyaniline Films  Y. Harima, K. Kishimoto, F. Ogawa, X. Jiang, and R. Patil [Full Text PDF(J-STAGE)]

A novel technique to study kinetics of chain conformation in polyaniline films is proposed. The technique is based on measurements of the intensity of 633 nm light reflected from the polyaniline-coated electrode upon application of constant anodic currents. The rate of transition from a coiled to an open-coil conformation is found to be 2–7 s−1 in HClO4 solution, depending on the film thickness and pH of the solution.

[Regular Article] Web Release Date: February 26, 2007

298-303 Two Dimensional and Three Dimensional Interactions between Bovine Serum Albumin and Chondroitin Sulfate  S. Xu and M. Yonese [Full Text PDF(J-STAGE)]

Soluble complex was formed when BSA molecules were added into Na2ChS solution. When increasing the molar ratio of BSA to Na2ChSγ, the spectra of mobility of complex solution changed from a single-peak to a double-peak, indicating free molecules appeared. The second peak nearing zero should be contributed by free BSA molecules because the mobility of BSA is almost zero at that pH.

[Regular Article] Web Release Date: February 26, 2007

304-317 Kinetics of Anionic Polymerization of Polybutadienyl Lithium in Benzene: An Osmotic Effect on Propagation Process  Y. Oishi, Y. Matsumiya, and H. Watanabe [Full Text PDF(J-STAGE)]

Decay of residual monomer fraction φ during anionic polymerization of polybutadienyllithium (PBLi) in benzene in presence/absence of chemically inert matrix PB. Small differences of M and C of hPBLi for the two cases have been corrected in the normalized time, tn. The difference of φ for these cases suggests that the polymerization proceeds through dissociated PBLi chains as well as their fused aggregates and the matrix chains osmotically suppress the latter route of polymerization.

[Regular Article] Web Release Date: February 26, 2007

318-329 Living Ring-Opening Metathesis Polymerization of Exo-Norbornenes Bearing Both Cyano and Ester Functionalities by a Well-Defined Ruthenium Catalyst  Y. Nishihara, Y. Inoue, A. T. Saito, Y. Nakayama, T. Shiono, and K. Takagi [Full Text PDF(J-STAGE)]

Exo-doubly fuctionalized polar norbornenes A and B bearing both cyano and ester groups were subjected to homopolymerization by ROMP with a Ru initiator 3 at low temperature. The synthesized homopolymers A and B showed Mn as high as 296,000 and a narrow PDI (<1.06). The rates of homopolymerizations of monomer A, B, and norbornene (C) were determined by the monitoring by the 1H NMR spectra. Synthesis of block and random copolymers from monomers A, B, and C via living polymerization was also attained.

[Regular Article] Web Release Date: February 26, 2007

330-341 Characterization of Rodlike Poly(n-hexyl isocyanate) Macromonomers and Their Polymacromonomers by Light Scattering, SAXS, Intrinsic Viscosity, and Scanning Force Microscopy  M. Kikuchi, T. Mihara, Y. Jinbo, Y. Izumi, K. Nagai, and S. Kawaguchi [Full Text PDF(J-STAGE)]

Poly(n-hexyl isocyanate) (PHIC) macromonomers and their cylindrical brushes consisting of PHIC chains have been prepared and characterized by SEC-MALS, small-angle X-ray scattering (SAXS), and viscometry in tetrahydrofuran (THF) and n-hexane at 25 °C. The molecular weight dependence of ‹Rg2›z of the brushes in THF may be quantitatively described in terms of the wormlike cylinder model with the parameters of λ−1=48 nm. Stiffness of the main chain remarkably increases by the presence of densely located rodlike chains.

[Regular Article] Web Release Date: February 26, 2007

342-346 Synthesis of Wholly Aromatic Polyketones Containing Optically Active Macrocycles  K. Maeyama, S. Maeda, H. Saito, and N. Yonezawa [Full Text PDF(J-STAGE)]

Wholly aromatic polyketones 7 containing bisbinaphthyl macrocycles were synthesized via P2O5-MsOH mediated direct condensation reaction of compound 3 with chlorobenzoic acids 4, nucleophilic aromatic substitution reaction of the resulting binaphthyl (5) with (S)-BINOL (1) in DMF/toluene, and NiBr2/Zn mediated aromatic coupling polymerization. The resulting polyketones 7 have excellent thermal resistance and solubility to organic solvents. Cyclic monomers 6 and polymers 7 have higher molar rotations based on optically active cyclic structures than pre-cyclized compounds 5.

[Regular Article] Web Release Date: February 26, 2007

347-358 Flame Resistant Nylon-6,6 Composites with Improved Mechanical Strength by the Combination of Additive- and Reactive-Type Flame Retardants  T. Kanno, H. Yanase, Y. Sugata, and K. Shigehara [Full Text PDF(J-STAGE)]

Characteristics of flame-resistant nylon-6,6 (PA66) composites with improved mechanical strength at high temperatures were studied. The composites prepared by mixing PA66 with organic phosphorus flame retardants of additive-type and reactive-type, the latter of which carrying allyl functionalities turned the resulting composite infusible after the γ-ray irradiation cross-linking. The storage modulus became constant after it increased with the exposure period or the amount of the reactive flame retardant. The composites with both additive- and reactive-type flame retardants realized the UL94/V-0 grade anti-flammability with satisfactory mechanical strength.

[Regular Article] Web Release Date: March 5, 2007

359-368 Normal Modes and Their Dispersion in α Form of Nylon-6 (αNY6)  S. K. Shukla, N. Kumar, A. K. Mishra, P. Tandon, and V. D. Gupta [Full Text PDF(J-STAGE)]

Nylon-6 [-(CH2)5–NHCO-]n (αNY6) is a synthetic polymer widely used in industrial applications. It has a planar zigzag conformation. A comprehensive study of the normal modes and their dispersion in αNY6 using Urey Bradley force field is being reported. Crossing between the various pairs of modes of dispersion curves have been explained as arising due to internal symmetry in the energy momentum space. The heat capacity derived from the dispersion curves via the density-of-states, is in good agreement with the experimental measurements obtained from the Athas data bank.

[Regular Article] Web Release Date: March 5, 2007

369-378 Preparation and Characterization of Polycaprolactone/Diclofenac Sodium and Poly(vinyl alcohol)/Tetracycline Hydrochloride Fiber Mats and Their Release of the Model Drugs  K. Kanawung, K. Panitchanapan, S. Puangmalee, W. Utok, N. Kreua-ongarjnukool, R. Rangkupan, C. Meechaisue, and P. Supaphol [Full Text PDF(J-STAGE)]

Selected SEM image (scale bar = 20 μm) of tetracycline hydrochloride (TH)-loaded electrospun poly(vinyl alcohol) fiber mat from 10% w/v PVA solutions (10 mL) loaded with the initial amount of TH of 0.5 g. The fiber mat was electrospun under the applied electrical potential of 8 kV over a collection distance of 10 cm.

[Regular Article] Web Release Date: March 5, 2007

379-388 Precise Synthesis of Poly(silphenylenesiloxane)s with Epoxy Side Functional Groups by Tris(pentafluorophenyl)borane as a Catalyst  L. Xue and Y. Kawakami [Full Text PDF(J-STAGE)]

Poly(silphenylenesiloxane)s with epoxy side groups were synthesized by cross-polycondensation of the hydrosilane, hydroxysilane and methoxysilane functional groups in the prepolymer and 1,4-bis(epoxys-functionalized methylsilyl)benzene in the presence of a catalyst. Tris(pentafluorophenyl)borane was found to be an excellent catalyst for the polymerization. The epoxy functional groups can be used to prepare the cross-linked structure of the polymers.

[Regular Article] Web Release Date: March 12, 2007

389-396 High Modulus and High Strength Fibers with High Electric Conductivity Prepared by Copper Electroless Plating on the Surface of Poly(p-phenylenebenzobisoxazole) (PBO)  M. Matsuo, H. Ishikawa, Y. Xi, and Y. Bin [Full Text PDF(J-STAGE)]

In attempt to produce high modulus and high strength fibers with high electric conductivity, copper plating on the surface of PBO fibers was carried out by using electroless plating, since PBO is a super-heat resistant polymer with the highest Young′s modulus among polymers but is an insulator. The mechanical and electrical properties of the plated fibers were investigated as a function of copper content. At the maximum volume fraction of copper, ca. 30.1 vol %, the electric conductivity reached 105.1 S/cm and the corresponding Young′s modulus was ca. 130 GPa.

[Regular Article] Web Release Date: March 12, 2007

397-403 Unassociated Molecular Chains in Physically Crosslinked Gellan Gels  S. Tanaka and K. Nishinari [Full Text PDF(J-STAGE)]

It was observed that gellan chains are released from physically crosslinked gellan gels into the external solution at 10 °C. The gellan concentration in the external solution increased with immersion time. It was suggested from differential scanning calorimetry (DSC) that the released gellan chains adopt a double helix conformation at 10 °C. The amount of released gellan chains decreased with increasing concentration of potassium chloride or calcium chloride in the external solution.

[Regular Article] Web Release Date: March 12, 2007

404-410 Grafting of Polymers onto Carbon Microcoil by Use of Carboxyl Groups on the Surface and Electric Properties of Conductive Composite Prepared from Silicone Rubber with the Polymer-Grafted Carbon Microcoil  H. Morohashi, Y. Takahashi, Y. Nishida, K. Fujiki, T. Yamauchi, N. Tsubokawa, and S. Motojima [Full Text PDF(J-STAGE)]

Poly(ethylene glycol) (PEG) was grafted onto the CMC surface by the reaction of carboxyl groups with PEG in the presence of condensing agents. Carboxyl groups on CMC surface have ability to initiate the cationic polymerization of vinyl monomers and the corresponding polymers were grafted onto the surface. Polymer-grafted CMC uniformly dispersed in good solvent for grafted chain and silicone rubber. The response of inductance, capacitance, and conductance of conductive composites of silicone rubber with the polymer-grafted CMC was discussed.