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  • This review sheds light on the living CDSA method, which can be used to precisely control length, shape, and branching during the self-assembly of amphiphilic block copolymers (BCPs) in the solution phase, leading to the creation of monodisperse 1D micelles with a crystalline core and solvated corona in a modular fashion. This paper also highlights the growth kinetics underlying the synthesis of cylindrical micelles via CDSA and its application in various fields, such as drug delivery, optoelectronics, and catalysis, which have been discovered recently.

    • Sipradip Mahapatra
    • Pradip Dey
    • Goutam Ghosh
    Review
  • Injectable hydrogels hold promise as cell delivery carriers for cell transplantation therapy in regenerative medicine. Injectable hydrogels possess various benefits, including biocompatibility, biodegradability, tissue adhesive properties, scaffold functions, and minimal invasiveness. To overcome the barriers in clinical translation, biological and physicochemical functionalization, which can improve delivery efficacy to the target and graft survival posttransplantation, is desirable. This review discusses the strategies to design injectable hydrogels for cell delivery and summarizes the approaches available to improve the biological and physicochemical features of hydrogels.

    • Akihiro Nishiguchi
    Focus Review
  • For the first time, this paper revealed that 2-picoline borane (pic-BH3) functioned well in the reductive amination of chitosan. Therefore, N-benzyl chitosan with a nearly perfect degree of substitution was successfully obtained, which has rarely been achieved by other synthetic methods. The new method herein has many advantages, including being more facile, more efficient, and less harmful than conventional methods; thus, this method is applicable to other aldehydes or ketones, leading to a wide variety of N-modified chitosan specimens with desirable degrees of substitution in the future.

    • Junpei Miyake
    NoteOpen Access
  • This study proposes a semiautomated system for synthesizing polyamic acid particles using a custom liquid-handling device and a robotic arm. Integrating cameras and a multimodal large language model enhances continuous monitoring and documentation, improving objectivity in synthetic experiments and enabling future advancements in research.

    • Kan Hatakeyama-Sato
    • Hiroki Ishikawa
    • Teruaki Hayakawa
    Original ArticleOpen Access
  • Blends of poly(lactic acid) (PLA) and thermoplastic starch (TPS) are promising biodegradable plastics, although their poor compatibility results in poor physical properties. In this study, oligo(lactic acid)-grafted starch (OLAgSt) was synthesized and added to PLA/TPS blends as a compatibilizer, and the physical properties of the obtained blends were evaluated. OLAgSt was synthesized by ring-opening polymerization of L-lactide using the hydroxy group of tapioca starch as an initiator. OLAgSt not only enhanced the dispersion of TPS within PLA, but also improved the biodegradability of the blend in a seawater environment.

    • Kazuki Shibasaki
    • Yu-I Hsu
    • Hiroshi Uyama
    Original Article
  • The gel-phase diagrams of temperature-responsive and biocompatible polymers with ethylene oxide (EO) side chains that differ in length were obtained. The gelation thresholds of the polymers depend not only on the monomer and crosslinker concentrations but also on the EO side chain lengths. Long EO side chains reduce the polymer overlap concentration. Furthermore, the EO side chains can engage in self-crosslinking, i.e., polymers can grow from the side chains depending on their length. These unique behaviors indicate that gelation occurs more readily with increasing the side chain length.

    • Takuma Kureha
    • Takuto Hirayama
    • Taichi Nishi
    Original Article
  • Induction of helical structures in peptides have been shown to increase their membrane permeability and facilitate cargo delivery applications. Our study has shown that substitution of an unnatural amino acid into a mitochondrial-targeting peptide induces a helical conformation that is maintained even after conjugation onto carbon nanotubes and confers increased membrane permeability. This led to an increase in DNA delivery efficiencies and gene expression into the mitochondria of intact plants when used as a DNA delivery system.

    • Simon Sau Yin Law
    • Mako Kuzumoto
    • Keiji Numata
    Original ArticleOpen Access
  • Optical resonators have attracted renewed attention in chemistry and biology as minute and highly sensitive sensors that work in the environment and inside biological tissues and cells without any connected wires. Optical resonators should be functional for facilitating molecular interactions and biological compatibility, which is, however, challenging with conventional materials and processing techniques. In contrast, the authors have been tackling this issue by using supramolecular chemistry. This article reviews our recent progress on the methodologies for making organic optical resonators and their emergent optical properties.

    • Hiroshi Yamagishi
    Focus Review
  • This study developed a novel method for the control of the cellulose crystal of cellulose I and II. The crystal transition from cellulose I to II was tracked when cellulose I, which is soaked in a low-concentration NaOH aqueous solution, was quenched using liquid nitrogen. The crystal transition progressed from the surface to the center of the sample. This quench treatment has the potential to fabricate new cellulose materials with a cellulose I core and a cellulose II surface.

    • Yuki Kugo
    • Takuya Isono
    • Kenji Tajima
    Note
  • This study presented the workflow of machine learning-guided optimization of Pd-immobilized porous polymer catalysts. Two independent variables (DVB and 1-decanol content) were involved in polymerization to maximize TOF as target variable in Suzuki–Miyaura coupling reaction. Bayesian optimization was applied for predictive modeling, and the optimized conditions were experimentally validated in subsequent iterations. By applying this workflow, the catalytic activity of immobilized polymer porous catalysts was successfully optimized using machine learning.

    • Xincheng Zhou
    • Hikaru Matsumoto
    • Yoshiko Miura
    Original Article
  • The crystalline surface using two photochromic diarylethenes was prepared to mimic a termite wing showing dual wettability. The surface is useful to correct small water droplets in the air. However, the crystalline system was not applicable for the use because crystalline structures on the surface melt under daylight. We copied the rough structure of crystalline film to a stable polycycloolefin polymer (Zeonex 480) surface. The copied surface showed the dual wettability as same as that of the crystalline surface.

    • Yuki Hashimoto
    • Amane Hase
    • Kingo Uchida
    Original Article
  • We have investigated the self-assembly kinetics of silica nanoparticles (SNPs) into the polymer-like structure by time-resolved small-angle X-ray scattering (SAXS). The analysis of the SAXS data with a kinetic model revealed that the SNPs undergo self-assembly in a process akin to the step-growth polymerization of bifunctional monomers. This study offers a facile strategy to construct polymer-like structures from isotropic spherical nanoparticles.

    • Tatsuki Oishi
    • Ayae Sugawara-Narutaki
    • Rintaro Takahashi
    Rapid CommunicationOpen Access
  • The relationships between the macroscopic mechanical properties and lamellar structures of polyamide 11 obtained from different heat treatments were investigated. From the tensile tests, the maximum stress and strain at necking increase with the heat treatment temperature. WAXS measurements indicated that different crystalline phases formed depending on the heat treatment conditions. SAXS revealed that the lamellar thickness and long period increased with the heat treatment temperature. Based on these results, we elucidated that the macroscopic mechanical properties correlate with the lamellar thickness and long period.

    • Toyoshi Yoshida
    • Mei Touji
    • Yoshihisa Kaneko
    Original Article
  • We explored the feasibility of Tetra-PEG gel, a controllable hydrogel, as a new biomaterial to develop a coating agent for post-ESD ulcers. We examined the optimal conditions for hydrogel application and developed a specialized catheter, then investigated its properties. Ultimately, we successfully used the optimized hydrogel and device to cover post-ESD ulcers in the porcine stomach. Further optimization of the hydrogel and ongoing research through animal experiments are expected to deepen our understanding of the material’s effects on ulcer healing and contribute to its clinical applications.

    • Rina Cho
    • Hiroyuki Kamata
    • Mitsuhiro Fujishiro
    Original ArticleOpen Access
  • Triptycene-containing polymers featuring a rigid propeller-shaped structure have attracted attention for a wide range of potential applications including guest recognition, material transports, separations, catalysis, and organic electronics. Herein, with a thorough literature survey, we present the synthesis of the various types of triptycenes that provide components for functional polymers. We particularly focus on triptycene-containing polymers and two-dimensional assemblies based on the space-filling design that uses nested packing. Future perspectives on the functionalities brought about by the design of triptycene-containing polymers and molecular assemblies are also discussed.

    • Fumitaka Ishiwari
    • Yoshiaki Shoji
    • Takanori Fukushima
    ReviewOpen Access
  • The effects of an organic monoglyceride (OMG) plasticizer on the crystallization of the PLLA/PDLA (50/50) blend were investigated by examining the isothermal crystallization of the blend with different contents of OMG (1–5 wt%) using POM, DSC, and time-resolved WAXD. It was found that the increase of the OMG content promoted the exclusive formation of stereocomplex crystallites and enhanced its crystallinity while suppressing the formation of homocrystals.

    • Neimatallah Hosni Mohammed Mahmoud
    • Hideaki Takagi
    • Shinichi Sakurai
    Original Article
  • The thiol-Michael polyaddition of three dialkynyl monomers with several dithiols proceeded using triethylamine as the catalyst to give unsaturated poly(ester-thioether)s with the expected structures (Mn, 2.4 × 103 to 22.6 × 103; molecular dispersity index [Mw/Mn], 1.26–2.00). All of the poly(ester-thioester)s had single glass-transition temperature values between −27 and 49 °C. While the rigid main chains improved the glass transition temperature, all of the poly(ester-thioester)s showed apparent enzymatic hydrolysis by lipase but low biodegradability in biodegradation tests using activated sludge.

    • Katsuhisa Yano
    • Akinori Takasu
    • Hiroshi Eguchi
    Original ArticleOpen Access
  • The Suzuki–Miyaura coupling reaction of BrC6H4-SiRR’-C6H4Br 1 with phenylboronic acid 3 in the presence of tBu3PPd precatalyst 4 and CsF/18-crown-6 produced a phenyl-disubstituted product, indicating that the Pd catalyst underwent catalyst transfer on the silylene group. The polycondensation of 1 and phenylenediboronic acid 2 yielded cyclic polymers even when excess 1 was used. The obtained cyclic polymers containing the silylene group showed stronger fluorescence in solution than did the methylene counterpart.

    • Natsumi Harada
    • Rina Yachida
    • Tsutomu Yokozawa
    Note
  • Three cyclic oxoester-thioester hybrid monomers were studied for anionic and cationic ring-opening polymerizations. Anionic polymerizations using thiol with 2,6-lutidine were successful for the chemoselective cleavage of the thioester with the thiol propagating end, exhibiting the living character to some extent. The polymerization in 2,6-lutidine without an initiator produced macrocyclic polymers. The cationic polymerizations occurred with the aid of CF3SO3H and benzyl alcohol but involved side reactions with low chemoselective ring cleavage. The thioester unit caused the polymers to exhibit a lower Tg with greater thermal and photo degradability.

    • Mao Hirata
    • Tomoki Yoshimatsu
    • Masato Suzuki
    Original ArticleOpen Access