Polymer Journal
Vol. 38, No. 10 (October, 2006)

[Review Article] Web Release Date: September 15, 2006

1005-1022 Morphology Control of Aromatic Polymers in Concert with Polymerization  K. Kimura, S. Kohama, and S. Yamazaki [Full Text PDF(J-STAGE)]

Morphology control methods of aromatic polymers by using polymerization reaction are reviewed. Many attractive methods have been launched including reaction-induced phase separation of oligomers, epitaxial polymerization, shear-induced chain orientation during gelation, template-based polymerization, suspension polycondensation, solid-state polycondensation and liquid-liquid interfacial precipitation and so on. Among them, the reaction-induced phase separation of oligomers possesses high potentiality to create novel polymer materials since it can control not only the morphology but also the molecular chain orientation. Polymer whiskers, microspheres and microspheres having needle-like crystals had been prepared.

[Regular Article] Web Release Date: August 30, 2006

1023-1034 2D NMR Analysis of Acrylonitrile/2-Methoxyethyl Acrylate Copolymers Synthesized by Atom Transfer Radical Polymerization  A. S. Brar and T. Saini [Full Text PDF(J-STAGE)]

The copolymerization of acrylonitrile (A) and 2-methoxyethyl acrylate (M) at three different molar in-feed compositions was carried out under atom transfer radical polymerization (ATRP) conditions using 2-bromopropionitrile (BPN) as initiator and CuCl/2,2′-bipyridine (bpy) as catalyst system in ethylene carbonate at 60 °C. A comprehensive microstructure analysis of A/M copolymers was performed utilizing various 2D (HSQC, TOCSY, and HMBC) NMR techniques in conjugation with 1D (1H, 13C{1H}, and DEPT) NMR experiments. The spectral assignments of carbonyl as well as nitrile carbons were done with the help of heteronuclear multiple bond correlation spectra.

[Regular Article] Web Release Date: August 30, 2006

1035-1042 Helix-Sense-Selective Free Radical Polymerization of N-(Triphenylmethyl)methacrylamide Derivatives  A. K. M. F. Azam, M. Kamigaito, and Y. Okamoto [Full Text PDF(J-STAGE)]

Two novel monomer, N-[(±)-(2-fluorophenyl)(4-fluorophenyl)(phenyl)methyl]methacrylamide (2F4FPhMAM) and N-[(4-butyl)triphenylmethyl]methacrylamide (BuTrMAM), were synthesized and polymerized in the presence of (+)- and (−)-menthol as the chiral additive at different temperatures. The obtained polymers, P2F4FPhMAM and PBuTrMAM, are optically active. P2F4FPhMAM is not soluble in common organic solvents, but PBuTrMAM is soluble in THF and chloroform. The polymers are almost 100% isotactic. The polymers obtained in the presence of various chiral additives had a prevailing helicity. The chiroptical properties of the obtained polymers were studied in detail.

[Regular Article] Web Release Date: August 30, 2006

1043-1054 Soluble Polyimides Based on Diaminobenzoic Acid Alkylester  Y. Tsuda, M. Kojima, and J. M. Oh [Full Text PDF(J-STAGE)]

The synthesis and characterization of a novel series of soluble polyimides, that are based on diaminobenzoic acid alkylester (DBAE) having long-chain linear alkyl groups with 8–14 carbon atoms, are described. Polyimides obtained from BTDA and DBAE-8–14, and copolyimides based on BTDA, DBAE-8–14, and DDE were insoluble, however, the incorporation of branched alkyl group or the use of relatively flexible diamine co-monomer, DDM improved the solubility. These polyimides based on DBAE were soluble in various polar solvents and exhibited good thermal stability.

[Regular Article] Web Release Date: September 7, 2006

1055-1060 Highly Isotactic Poly(vinyl alcohol) Derived from tert-Butyl Vinyl Ether V. Viscoelastic Behavior of Highly Isotactic Poly(vinyl alcohol) Films  H. Ohgi, T. Sato, H. Watanabe, and F. Horii [Full Text PDF(J-STAGE)]

Dynamic viscoelasticity was compared for PVAs of various stereoregularities (mm=0.14–0.78). The αa and βa dispersions reflecting the chain motion in the non-crystalline region hardly change with the stereoregularity. In contrast, the αc and βc dispersions in the crystalline region significantly change with the stereoregularity. This change can be related to a difference in the chain mobility in the crystals that reflects a difference in the magnitude of the intramolecular and intermolecular hydrogen bonding of the chains in respective crystals.

[Regular Article] Web Release Date: September 15, 2006

1061-1067 Self-Assembly of Stereocomplex-Type Poly(lactic acid)  Y. Furuhashi, Y. Kimura, and N. Yoshie [Full Text PDF(J-STAGE)]

Self-assembly behavior of enantiomeric poly(lactic acid) were examined, especially focusing on the stereocomplex formation between poly(L-lactic acid) and poly(D-lactic acid). The casted specimens from dilute solution of 1,4-dioxane were examined using differential scanning calorimetry, wide-angle X-ray diffraction, and atomic force microscopy. It is confirmed that stereocomplex formation is enhanced via homo crystallization upon annealing, because of the easier insertion of enantiomers. The annealing promotes the alignment of the molecular chains, inducing the alternative insertion of deposited enentiomeric molecular chains.

[Regular Article] Web Release Date: September 7, 2006

1068-1073 Preparation of Fully Aromatic Polysilarylenesiloxanes by Melt Polycondensation and Their Thermal Properties  H. Ito, E. Akiyama, Y. Nagase, A. Yamamoto, and S. Fukui [Full Text PDF(J-STAGE)]

The melt polycondensation of the two kinds of monomers, 1,4-bis(hydroxydiphenylsilyl)benzene and 4,4′-bis(hydroxydiphenylsilyl)biphenyl was investigated, and the thermal properties of the obtained polymers were studied. The IR spectra and the XRD patterns of the polymers indicated that the melt polycondensation occurred in the temperature range from 290 °C to 400 °C. The polymers obtained from 4,4′-bis(hydroxydiphenylsilyl)biphenyl showed no phase transition below 400 °C. It was resulted from the cross-linking reaction occurred simultaneously with the condensation reaction of the silanols.

[Regular Article] Web Release Date: September 15, 2006

1074-1080 Synthesis and Properties of a Novel High Sensitive Photo-Radical Initiator Based on Biphenyl-2,2′-Dicarboximide Derivatives  K. Sakayori, Y. Shibasaki, and M. Ueda [Full Text PDF(J-STAGE)]

A new high sensitive photo-radical initiator N-[2-(2-acryloyloxyethoxy)ethyl]biphenyldicarboximide (BDI-5) with good thermal stability was developed. BDI-5 has high thermal stability over 300 °C. BDI-5 acts as a hydrogen transfer type photo-initiator in the presence of triethanolamine (TEA) and has good compatibility with a matrix such as pentaerythritol triacrylate (PETA). The photosensitivity of BDI-5 with TEA for the polymerization of PETA was comparable to the excellent photo-radical initiators, 2-methyl-4′-(methylthio)-2-morpholinopropiophenone (Irg907).

[Regular Article] Web Release Date: September 15, 2006

1081-1088 Dielectric Normal Mode Relaxation of Poly(propylene oxide) and Poly(butylene oxide) in Dilute and Semidilute Solutions  H. Nishimura, O. Urakawa, and K. Adachi [Full Text PDF(J-STAGE)]

We investigated the dielectric normal mode relaxation in dilute and semidilute solutions of poly(propylene oxide)(PPO) and poly(butylene oxide)(PBO) in benzene which is a good solvent for PPO but a marginal solvent for PBO. The normal mode relaxation times τn in dilute solutions of PPO and PBO are proportional to [η]Mw in agreement with the Rouse-Zimm theory where [η] and Mw denote the intrinsic viscosity and weight average molecular weight, respectively. With increasing concentration C, τn increases in proportion to C[η]. The dynamic crossover concentration has been determined by using the dynamic scaling theory. The concentration dependence of ‹ r2› determined from the relaxation strength agrees approximately with the scaling theory.

[Regular Article] Web Release Date: September 15, 2006

1089-1092 Equilibrium Melting Temperature of Aliphatic Polyesters Using Model Compounds  M. Okeda, Y. Ogawa, and N. Matsumoto [Full Text PDF(J-STAGE)]

A series of oligomers for use as a biodegradable aliphatic polyester model compounds such as poly(dodecamethylene dodecanedioate) (C12-n) and poly(tetradecamethylene tetradecanedioate) (C14-n) were synthesized. The melting enthalpies and entropies of n-mers were observed to follow a linear equation in terms of n. The equilibrium melting temperatures Tm0 of C12-n and C14-n obtained from Δ H/Δ S were 104 °C and 108 °C, respectively. We can easily calculate the approximate Tm0 of aliphatic polyesters.

[Note] Web Release Date: August 30, 2006

1093-1097 Providing Natural Water Structure Surrounding Highly Mobile Maltose Groups Conjugated with Polyrotaxanes  H. Hirose, H. Sano, G. Mizutani, M. Eguchi, T. Ooya, and N. Yui [Full Text PDF(J-STAGE)]

Raman and differential scanning calorimetry (DSC) measurements of aqueous solutions containing maltose-polyrotaxane conjugates reveal that maltose groups with high mobility well fit the network structure of surrounding water, leading to an increase in the amount of bound water to preserve bulk water clusters.