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  • Multiarmed cyclosiloxanes bearing terminal amine groups (DnA, n = 4, 5) were obtained via a photocatalytic thiol-ene reaction, with regioselectivities of β-adducts as high as 93% irrespective of the repeating unit number in the cyclosiloxane rings. Ketoenamine-linked hybrid networks using D4A and D5A as the starting monomers were successfully synthesized via a mild Schiff base reaction with 2,4,6-triformylphloroglucinol and demonstrated high thermal stability and the formation of nanoparticle assemblies.

    • Huie Zhu
    • Yuhi Watanabe
    • Masaya Mitsuishi
    Original Article
  • Academia and industry are interested in using autotrophic microorganisms as a sustainable/green production platform to produce biochemical products and commercially relevant commodities, including biopolymers. Unlike heterotrophs that require carbohydrates and amino acids for growth, autotrophs have evolved to fix carbon dioxide and drive metabolic processes utilizing either light (photoautotrophs) or chemical compounds (chemolithotrophs) as energy sources. Here, we review the current state-of-the-art in the construction of autotrophic microbial cell factories for efficient biopolymer production and recent breakthroughs in natural autotrophs focusing on biopolymer production.

    • Pisanee Srisawat
    • Mieko Higuchi-Takeuchi
    • Keiji Numata
    Review Open Access
  • Postfunctionalization of aromatic C – H bonds at the main chains of π-conjugated polymers (CPs) is ideal for tuning various functionalities of precursor CPs. In this study, we investigated the electrochemical C – H phosphonylation of the main chain of poly(3-hexylthiophene) (P3HT). Anodic phosphonylation of P3HT was successfully achieved using trialkyl phosphite as an electrically neutral nucleophile in the presence of nonnucleophilic dopants. The chemical structures and the optoelectronic properties of phosphonylated P3HT were characterized. The introduction of phosphonate moieties into the main chain of CPs is potentially useful for improving their processibilities and imparting sensing abilities to them.

    • Kohei Taniguchi
    • Tomoyuki Kurioka
    • Shinsuke Inagi
    Original Article
  • Cationic block copolymers consisting of quaternized pyridinium salt and hydrophobic acrylate segments were synthesized and their basic properties as ink dispersants were evaluated. Among all polymers, the copolymer of 4-vinylpyridine and butyl acrylate shows the best properties in rheology and dispersion stability. However, further optimization of molecular design is necessary to achieve suitable redispersion properties as ink dispersants. Through this study, we demonstrated the potential of cationic block copolymers as ink dispersants and the issues that need to be improved for better ink performance.

    • Toshihiro Ohtake
    • Hiroshi Ito
    • Naoyuki Toyoda
    Original Article
  • Using interfacial-sensitive sum-frequency generation (SFG) spectroscopy, it was found that incorporation of bulky and polar maleic anhydride (MA) into polystyrene (PSt) chains in an alternating manner, forming an alternating copolymer of P(St-alt-MA), led to reductions in π-π and dipolar interactions at the air interface relative to those in the bulk and thus greater Tg confinement effect for the alternating copolymer. The results demonstrate the crucial impacts of interfacial interactions on polymer dynamics under confinement.

    • Zhexiao Xing
    • Ningtao Zhu
    • Biao Zuo
    Original Article
  • Reverse osmosis (RO) membranes composed of polyamides and cellulose acetates are used as separation layers in pure-water production. However, improving the separation performance and antifouling properties of RO membranes is necessary. This focus review described the composite reverse osmosis membranes with optimal amounts of polyhedral oligomeric silsesquioxanes (POSS), which are cage-shaped, subnanosized molecules exhibiting organic–inorganic hybrid structures, showed improved water flux, NaCl rejection, antichlorine and antifouling properties, and mechanical strength.

    • Kazuki Yamamoto
    Focus Review
  • Nanosized keratin particles (Ker-DODAC) were prepared via the assembly of keratin chains with the aid of a cationic surfactant. The obtained nanoparticles (Ker-DODACss) possessed a hydrophobic core composed of surfactants. To modify its internal environment, cholesterol was loaded to nanoparticles. The obtained nanoparticles (Ker-DODACss-Chol) showed retention and release of payloads in response to multiple stimuli. Also, lipophilic antioxidants, α-tocopherol, was loaded to Ker-DODACss-Chol to prevent α-tocopherol from an oxidative degradation and to preserve the antioxidant activity.

    • Yuuka Fukui
    • Kaori Ito
    • Keiji Fujimoto
    Original Article
  • Supramolecular nylon-based materials exhibited changes in their Young’s moduli and underwent bending upon irradiation with UV light as a result of isomerization in 1:2 complexes of γ-cyclodextrin and azobenzene. The photoisomerization of azobenzenes led to photoresponsive actuation of the supramolecular materials. The movable cross-links contributed to the mechanical toughness and photoresponsive actuation of these materials. Shape restoration of the nylon-based materials resulted in an extraordinarily high work efficiency.

    • Junsu Park
    • Hiroki Tamura
    • Yoshinori Takashima
    Original Article
  • The results of comprehensive research on the thermal behavior, molecular and crystalline structures of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV) films of different thicknesses, their molecular weights (Mw) and 3-hydroxyvalerate (3-HV) contents are reported. The film thickness affects the PHB film crystalline structure and crystallinity. A decrease in Mw leads to a smaller number of piezoactive domains in PHB films. The addition of HV significantly reduces the crystallinity and piezoresponse of PHB films. A decrease in Mw results in the increased crystallinity of PHB-HV films.

    • Roman V. Chernozem
    • Igor O. Pariy
    • Maria A. Surmeneva
    Original Article
  • An approach inspired by biomineralization has allowed us to develop various organic/inorganic hybrid materials with environmental benignity. In the present study, we have achieved the orientation control of zinc hydroxide carbonate (ZHC) thin-film crystals through the chemical structures and morphologies of the templates. After the thermal treatment of the ZHC thin films, the crystal orientations of the resultant zinc oxide (ZnO) thin films are maintained. The effects of the thickness and annealing time for the polymer templates on the formation of ZnO thin films have been examined.

    • Takahiro Mikami
    • Shunichi Matsumura
    • Takashi Kato
    Original Article Open Access
  • Mannich-type polycondensation of diamines, bisphenols and PF was conducted in CHCl3, CHCl3/triethylamine, and CHCl3/triethanolamine, respectively. The products were greatly affected by the solvents used. Owing to the combination of alkalinity and solvation effect of triethanolamine, CHCl3/triethanolamine was preferable for Mannich-type polycondensation which gave main-chain benzoxazines possessing Mn up to 10,000, oxazine content >80.0% and yield >96.0%.

    • Ping Wang
    • Xuya Liu
    • Po Yang
    Original Article
  • We describe the synthesis of polycarbonate (PC) by means of the polycondensation of diol formate and dialkyl carbonate through an ester-carbonate exchange reaction. Furthermore, the polycondensation of diol formate and diethyl carbonate in the presence of polyester (PEs) under reduced pressure affords a statistical copolymer of PC and PEs. The composition of PC and PEs in the copolymer can be arbitrarily altered by changing the feed ratio of the monomers to PEs.

    • Takayoshi Katoh
    • Maai Saso
    • Tsutomu Yokozawa
    Original Article
  • The effect of the nucleating agent masterbatch carrier resin on the nonisothermal crystallization of a pipe-grade polypropylene block copolymer was investigated at three different cooling rates using differential scanning calorimetry (DSC). Crystallization kinetic parameters obtained from DSC cooling curves showed that incorporation of a nucleating agent by means of a masterbatch increased the crystallization rate by approximately two times compared to that of the sample with the same concentration of nucleating agent without the use of a masterbatch.

    • Maryam Shokrollahi
    • Bahereh T. Marouf
    • Reza Bagheri
    Rapid Communication
  • A pair of the oppositely charged diblock copolymer was used to prepare the polyion complex (PIC) micelle by mixing them in an aqueous medium using electrostatic, hydrophobic, and π–π interactions. The PIC micelles attained the maximum size and aggregation number when the charges of the cationic and anionic blocks were neutralized. The PIC micelle was stable against NaCl because the core was formed by electrostatic, hydrophobic, and π–π interactions. The micelle can encapsulate charge and hydrophobic guest molecules.

    • Thu Thao Pham
    • Tien Duc Pham
    • Shin-ichi Yusa
    Original Article
  • The encapsulation of polymer chains into MOF pores is a powerful strategy for controlling polymer chain assemblies at the molecular level. In this focus review, recent developments of hybridization of conjugated polymers and MOFs are described. This approach can facilitate the study of the inherent optoelectronic properties of conjugated polymers. Furthermore, the formation of nanocomposites can provide unprecedented material platforms to accomplish nano-synergistic functions.

    • Takashi Kitao
    Focus Review
  • We investigated stereospecific copolymerization of styrene with p-divinylbenzene (DVB) using an aryl-substituted [OSSO]-type zirconium(IV) precatalyst with dried modified-methylaluminoxane (dMMAO) as an activator. The resulting poly(iso-styrene‐co‐DVB)s possessed very high molecular weights (Mw = 93,000−131,000 g mol−1) and unimodal polydispersity indices (PDI = 1.8−2.5). The DVB contents (7–20 mol %) in the copolymer could be varied depending upon the feed concentration. These copolymers exhibited an amorphous phase structure with glass transition temperatures (Tg values) of 84.8–110.9 °C.

    • Kazuaki Nakamura
    • Takuya Kishi
    • Norio Nakata
    Note
  • Organic compounds with conjugated carbonyl groups used as electrode material for secondary battery is attractive attention. We have been focused on disodium terephthalate and its polymer derivative as active anode material for secondary battery. Herein, we synthesized a novel vinyl polymer bearing an extended conjugated disodium dicarboxylate and it was evaluated as an anode active material for sodium-ion battery to discuss the correlation between structure and electrochemical properties. We suggest that the longer π-extended systems on the side chains provide a better anode performance of sodium-ion batteries.

    • Kazuki Sugawara
    • Naoaki Yabuuchi
    • Makoto Miyasaka
    Original Article
  • Poly(substituted methylene)s possess higher dense side chains and their chain mobilities are restricted, relative to conventional vinyl polymers. The surface of poly(substituted methylene)s was more hydrophobic. In particular, the poly(substituted methylene) with perfluoroalkyl groups showed lower surface free energy than the corresponding vinyl polymer. Moreover, the surface of block-like copolymer of poly(substituted methylene) was more hydrophobic than that of random copolymer. The preparation methods of films of poly(substituted methylene) with ethyl ester side chains controlled their surface free energies and structures.

    • Takuya Matsumoto
    • Eichi Kannan
    • Takashi Nishino
    Original Article