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Volume 45 Issue 7, July 2013

Rapid Communication

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Invited Review

  • A number of biomaterials have been proposed, including hydrophilic, phase-separated and zwitterionic polymers. It has not been clearly elucidated which mechanisms are responsible for biocompatibility on a molecular level. Water interactions have been recognized as a fundamental part of the biological response to contact with biomaterials. We have proposed the ‘intermediate water’ concept; the water exhibited both clear peak for cold crystallization in differential scanning calorimetry chart and a strong peak at 3400 cm−1 in a time-resolved infrared spectrum. We found the localized hydration structure consisting of the three hydrated water in poly(2-methoxyethyl acrylate) (PMEA).

    • Masaru Tanaka
    • Tomohiro Hayashi
    • Shigeaki Morita
    Invited Review
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Focus Review

  • The electrostatic self-assembly and covalent fixation (ESA-CF) process, in conjunction with click chemistry and olefin metathesis, was used to construct selectively a variety of unprecedented polymer architectures, such as manacle-shaped and tandem multicycles, as well as doubly fused tricyclic and triply fused tetracyclic topologies. Moreover, the self-assembly of a cyclic amphiphilic block copolymer, which was prepared by intramolecular metathesis, produced a micelle with an approximately 50 °C increase in thermal stability compared with the one from the linear prepolymer. Single-molecule spectroscopic studies also revealed different diffusion modes for cyclic and linear polymers.

    • Takuya Yamamoto
    Focus Review
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Original Article

  • Addition and ring-opening metathesis polymerizations of new monomers (Me3Si- and Me3Ge-substituted tricyclononene and tricyclononadienes) were carried out on Pd- or Ni-catalyst systems and Grubbs first-generation catalyst, respectively. New addition polymers were obtained with good yields up to 70% and molecular weight (Mw) up to 5.6 × 105. The yields of the first obtained metathesis polymers were higher than 80% and Mw were up to 8.8 × 105. It was shown that the novel addition polymer poly[(3-trimethylgermyl)tricyclononene-7] possesses high gas-transport parameters and solubility-controlled permeation of gaseous hydrocarbons.

    • Maxim Bermeshev
    • Boris Bulgakov
    • Eugene Finkelshtein
    Original Article
  • Ab initio statistical mechanics based on the rotational isomeric state scheme and molecular orbital calculations has been applied to poly((R)-3-hydroxybutyrate)(PHB) to elucidate its conformational characteristics and configurational properties. This article presents fully consistent interpretations on its bond conformations, solution properties, crystal structure, thermal properties and interactions with a PHB depolymerase in terms of the conformational characteristics.

    • Yuji Sasanuma
    • Shiori Katsumata
    Original Article
  • Composite polyether electrolytes filled with oriented MMT layers in perpendicular (M) or parallel (M//) to the film surface were successfully obtained by the application of strong magnetic field. The ionic conductivity of the M composite with 5 wt% of Li-MMT was 1.2 × 10−5 S cm−1 at 30 °C, and the value was more than six times greater than that of the original electrolyte (PMEO10LiClO4). We concluded that the ionic migration on the layer of oriented MMT has a crucial role to increase the conductivity with lower activation energy.

    • Shunsuke Kitajima
    • Masahiro Matsuda
    • Yoichi Tominaga
    Original Article
  • A series of maleimide–thiophene copolymers presenting pendent 2-hydroxyethyl and 6-hydroxyhexyl units were synthesized. The maleimide–thiophene copolymers containing different contents of OH groups were then reacted with 3,3′-dimethoxy-4,4′-biphenylene diisocyanate in solution to form the interchain-linked polymers. The photovoltaic performances of the PSCs incorporating the interchain-linked copolymers were superior to those of the corresponding PSCs based on the OH-containing copolymers.

    • Rong-Ho Lee
    • Wei-Yu Chen
    • Sheng-Yi Shiau
    Original Article
  • 4,4′-Bismaleimidediphenylmethane (BMI) was cured finally at 250 °C with cardanol (CD) or CD novolac (CDN) prepared by the reaction of CD and paraformaldehyde with CD/maleimide unit ratios 1/2, 1/4 and 1/6. The obtained cured resins with CD/maleimide ratio lower than 1/2 did not show glass transition until 300°C and had 5% weight loss temperature higher than 450°C. The curing mechanism was elucidated by means of the proton nuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FTIR) analyses of the model reaction products of CD and N-phenylmaleimide (PMI) and the cured resins.

    • Mitsuhiro Shibata
    • Yusuke Itakura
    • Hironori Watanabe
    Original Article
  • Bis-pyrrolidone-type monomers (obtained from itaconic acid, which is a renewable chemical identified in the top 12 value-added chemicals from biomass) with alkylidene spacers of variable size were synthesized and polycondensed with various diamines. The resulting polycondensates were used as compatibilizers to improve interfacial adhesion in poly (butylene succinate) (PBS)/plasticized starch blends. The interfacial adhesion between PBS and plasticized starch was improved using these polycondensates.

    • Farouk Ayadi
    • Saskia Mamzed
    • Patrice Dole
    Original Article
  • Pentaerythritol-zinc (Penzinc) has been synthesized and its thermal stability, especially its synergism with β-diketone and calcium stearate, was characterized. Experimental results show that PVC stabilized with complex of Penzinc and β-diketone has an excellent initial color and long-term thermal stability. Moreover, the thermal stability mechanism of Penzinc and β-diketone are also discussed with the help of quantum chemical calculations. Results indicate that both α-H atom of β-diketone and zinc atom of Penzinc, having low electron density, can easily react with labile chloride atom of PVC, which has high electron density.

    • Degang Li
    • Min Zhou
    • Shouyu Tang
    Original Article
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