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  • A novel block copolymer, poly(3-hexylthiophene)-b-poly(vinyl catechol) (P3HT-b-PVC) was successfully synthesized via a Click reaction between chain-endfunctionalized P3HT with an alkyne group (P3HT-Alkyne) and chain-end-functionalized poly(3,4-di-tert-butyldimethylsilyloxystyrene) with an azide group (PSVC-Azide), followed by deprotection of tert-butyldimethylsilyloxy groups from the PSVC-Azide segment. Tape test results showed that the adhesion property of the P3HT-b-PVC film was considerably better than that of the corresponding P3HT film. Furthermore, despite the presence of an insulating PVC block in P3HT-b-PVC, the P3HT-b-PVC thin film exhibited a hole mobility comparable to that of the corresponding P3HT thin film.

    • Shin Inagaki
    • Kazuhiro Nakabayashi
    • Tomoya Higashihara
    Rapid Communication
  • Achieving a wearable artificial kidney hinges on overcoming the critical challenge of developing efficient urea adsorption materials for dialysate regeneration. An acidic hollow polystyrene nanoparticle was synthesized by modified emulsion polymerization, DMF etching and sulfuric acid treatment sequentially. The nanoparticles had a urea absorption capacity of up to 1 mmol/g after two hours of adsorption in a 30 mM urea aqueous solution at 37 °C. Additionally, the adsorption capacity dramatically increased with increasing urea concentration, while sharply decreased with increasing ionic strength.

    • Yiheng Huang
    • Yifan Jiang
    • Yong Guo
    Rapid Communication
  • The aggregation states from the interface to the bulk of the adhesive/adherend is a key to unraveling adhesion at the molecular level. We applied X-ray absorption spectroscopy (XAS) in combination with an Ar gas cluster ion beam (Ar GCIB) to poly(methyl methacrylate) (PMMA) films adsorbed onto a SiOx/Si(111) surface. GCIB-XAS analysis revealed that the orientation of the C=O group in the side chain of PMMA differs between the region from the SiOx interface to a distance on the order of 1 nanometer and the bulk PMMA region.

    • Hiroyuki Yamane
    • Masaki Oura
    • Takaki Hatsui
    Rapid CommunicationOpen Access
  • The effects of the addition of a hyperbranched polymer (HBP) on the degradability characteristics of linear polyglycolide (PGA) fiber mats. It was revealed that HBP acted as a plasticizer, especially in underwater environments. The weight loss of the PGA fiber mats was accelerated with increasing HBP content. Considering that the structural changes in the PGA crystals depended on the feed amount of HBP, it was claimed that HBP promoted PGA degradation in both the amorphous and crystalline phases.

    • Reiki Eto
    • Haruki Mokudai
    • Keiji Tanaka
    Rapid Communication
  • We designed multiblock amphiphilic cyclophanes that possess twisted aromatic units with axial chirality. Electronic absorption and emission spectroscopy revealed that these cyclophanes are molecularly dispersed in organic solvents, while they form aggregates in aqueous environments. We also found that under aqueous conditions, the chiral aromatic units within homochiral cyclophanes adopt a more planar conformation compared to their diastereomer, demonstrating the possibility of stereoselective recognition. Furthermore, by comparing the corresponding multiblock amphiphiles that are linear and chiral, we found that the macrocyclic structure might be essential for recognition.

    • Ryoto Matsuda
    • Haruki Otake
    • Kazushi Kinbara
    Rapid Communication
  • Inspired by mussel adhesion, polydopamine ultrathin films were formed at silicone oil/water interfaces even in neutral solutions. The MCF-7 cells successfully adhered to the oil/water interface without aggregation during cell growth. The interfacial wrinkles were induced by changes in the oil volume and the compressive stress, and the MCF-7 cells adhered to the oil/water interface and were arranged along the wrinkles. The polydopamine interfacial films provide new opportunities to investigate the relationships between toughness and patterns for tissue engineering and regenerative medicine.

    • Hiroya Abe
    • Tomoya Ina
    • Matsuhiko Nishizawa
    Rapid Communication
  • The grazing incidence diffracted X-ray blinking was proposed to evaluate the molecular motions occurring at polymer surfaces by measuring X-ray diffraction patterns near the total reflection angle over small time periods. When the crystallized polymer poly{2-(perfluorooctyl)ethyl acrylate}(PC8FA) film was measured, the results of the decay constants, which are indexes of molecular motions, suggested that the PC8FA surface is mobile compared to the bulk.

    • Rena Inamasu
    • Hiroki Yamaguchi
    • Yuji C. Sasaki
    Rapid CommunicationOpen Access
  • We demonstrated biomolecular motors driven swarming of microtubules and their dissociation under UV and visible light irradiation, respectively. A photoresponsive molecule, para tert-butyl-substituted azobenzene was incorporated to the backbone of single strand DNA, which functions as a photoswitch to control the swarming of microtubules in a reversible manner. This work is expected to expand the potential applications of biomolecular motors in developing photoregulated molecular machines.

    • Satsuki Ishii
    • Mousumi Akter
    • Akira Kakugo
    Rapid Communication
  • The first ultrasoft aqueous lithium-ion batteries with coaxial fiber structures were fabricated with an all-hydrogel design. The all-hydrogel fiber aqueous Li-ion battery exhibited a high specific discharge capacity of 84.8 mAh·g−1 and superior cycling behavior and rate capacity performance. A low Young’s modulus (e.g., 445 kPa) for the battery was achieved by making it entirely from hydrogels, which ensured mechanical compatibility with biological tissues.

    • Jiacheng Wang
    • Tingting Ye
    • Ye Zhang
    Rapid Communication
  • The liquid-phase exfoliation of graphite is mass-producible and cost-effective method of graphene production. Polymers can be employed as dispersants to facilitate the exfoliation of graphite in organic solvents. We synthesized methacrylate polymers with various monomer ratios and molecular weights and investigated the efficient acquisition of graphene from graphite. Graphene with a uniform thickness was obtained when graphite was exfoliated using an optimized polymer dispersant.

    • Shimpei Takeda
    • Yuta Nishina
    Rapid Communication
  • 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
  • Using a facile method, a gelatin hydrogel with anisotropic gel properties was prepared on a substrate via hydrogelation to induce self-assembly. Three kinds of surface properties (structural control factors) of the template induce the formation of an anisotropic gelatin network by self-assembly. The swelling behavior and mechanical properties of the anisotropic and isotropic gelatin hydrogels are different. When the hydrogel is compressed in a direction perpendicular to the tube-like gelatin network, the inner space of the network is compressed.

    • Kohei Kawaguchi
    • Syuuhei Komatsu
    • Kazuki Murai
    Rapid Communication
  • This work studied the crosslinking of PLA/star-shaped polycaprolactone to enhance the toughness and resistance to thermal deformation of PLA. The tensile and thermal properties of the blend and crosslinked films were investigated. The simple test of resistance to thermal deformation by immersing in hot water was done. The crosslinked film shows resistance to deforming in hot water (80 °C, above its Tg).

    • Chantiga Choochottiros
    Rapid Communication
  • Polytetrafluoroethylene (PTFE) has a weak boundary layer (WBL) on the surface. A cross-section of PTFE was observed using a scanning electron microscope for investigating the difference in morphology between WBL and bulk layer. Large voids of 0.5–2.0 µm in diameter were observed on the surface side of PTFE but not on the bulk side. These voids existed up to approximately 5 µm from the outermost surface of the PTFE. This result indicated that the thickness of WBL of PTFE was in the order of single µm.

    • Yosuke Seto
    • Misa Nishino
    • Yuji Ohkubo
    Rapid Communication
  • An optically active acylhydrazine-functionalized biphenyl (AHB) carrying L-alanine-derived oligoamide side chains supramolecularly coassembled with the corresponding achiral AHB to form a one-dimensional helical nanofiber, in which intermolecular hydrogen bonding between the chiral/achiral oligoamide pendant units resulted in modest chiral amplification (the sergeants-and-soldiers effect). The chiral/achiral AHB-based covalent copolymers folded into a preferred-handed helical structure with amplification of the helical sense excess driven by intramolecular hydrogen bonds and further polymerized into a higher molar mass supramolecular helical polymer stabilized by end-to-end intermolecular hydrogen bonding.

    • Tomoyuki Ikai
    • Satoshi Kawabata
    • Eiji Yashima
    Rapid Communication
  • Composites of fluoropolymer (FKM) and nano-carbon fillers have been considered as sealing materials for hydrogen fuel storage. We here characterize, structurally and dynamically, FKM chains adsorbed on single-walled carbon nanotubes (SWCNTs) and carbon black (CB), which were prepared by a solvent leaching method.

    • Daisuke Kawaguchi
    • Kazuki Sasahara
    • Keiji Tanaka
    Rapid Communication
  • For n-type organic semiconductors, low thermoelectric conversion properties are an issue that needs to be resolved, moreover current manufacturing methods are not compatible with printing technology. In this communication, we report the systematic preparation of carbon nanotube (CNT) sheets containing dopant polymers using a drop-casting method that enhances thermoelectric performance. The inclusion of 1,2-diphenylhydrazine as a secondary dopant significantly improved the ZT value of poly(N-vinyl-2-pyrrolidone)-poly(vinyl alcohol) graft copolymer/CNT, from 5.26 × 10−3 for the undoped system to 1.34 × 10−2. The developed approach, which is expected to provide on-demand manufacturing through printed electronics technologies.

    • Shinichi Hata
    • Jin Tomotsu
    • Naoki Toshima
    Rapid Communication
  • A fluorescent microarray comprising polythiophene-based chemosensors functionalized with pyridinium boronic acid has been developed for the detection of the components of sake such as glucose and pyruvate. The sensor microarray was fabricated on a glass chip for on-site detection utilizing imaging analysis and pattern recognition. The selected four nondiluted sake samples were discriminated by the cross-reactive response pattern. Moreover, the facile chemosensor array realized the prediction of unknown concentrations of glucose and pyruvate in the diluted sake, which indicated its usability for drink analysis.

    • Xiaojun Lyu
    • Akira Matsumoto
    • Tsuyoshi Minami
    Rapid Communication
  • A novel superabsorbent polymer crosslinked with diacylhydrazine DC-SAP was prepared. A very-high water uptake (ca. 80,000%) was observed in DC-SAP at a crosslinking ratio of 1%. The swollen gel was instantly (<5 s) solubilized by treatment with a small amount of sodium hypochlorite solution. A commercially available bleacher could also be used for the solubilization of DC-SAP. Despite the high degradability of DC-SAP, it exhibited high chemical and thermal stability. The decomposition product is composed of pure poly(sodium acrylate), which is extremely safe substance.

    • Kazuya Yanaze
    • Nobuhiro Kihara
    Rapid Communication
  • A novel thermoresponsive diblock copolymer of methyl poly (ethylene glycol)-b-poly (O-benzyl-L-threonine) was synthesized. The copolymer solutions exhibited gel-to-sol UCST transition behavior with temperature. The gel-to-sol transition was due to the disassembly of the initial β-sheet layered nanoassemblies that induced the transformation of self-organized morphology from nanosized fibrils to spherical aggregates.

    • Hongyu Zhu
    • Dongxu Gu
    • Jianyuan Hao
    Rapid Communication