Polymer Journal最新文献

{"title":"Facile and efficient synthesis of N-benzyl chitosan via a one-pot reductive amination utilizing 2-picoline borane","authors":"Junpei Miyake","doi":"10.1038/s41428-024-00933-6","DOIUrl":"10.1038/s41428-024-00933-6","url":null,"abstract":"In this paper, the use of 2-picoline borane (pic-BH3) as a reducing agent for the reductive amination of chitosan is reported for the first time. By optimizing the feed molar ratio of chitosan, benzaldehyde and pic-BH3, a high yield of isolated N-benzyl chitosan with a nearly perfect degree of substitution is successfully obtained. This material has rarely been obtained with previous methods. The newly developed synthetic 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 wide varieties of N-modified chitosan in the future. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 10","pages":"925-931"},"PeriodicalIF":2.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00933-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improvement in the physical properties of poly(lactic acid)/thermoplastic starch blends using oligo(lactic acid)-grafted starch","authors":"Kazuki Shibasaki, Yu-I Hsu, Hiroshi Uyama","doi":"10.1038/s41428-024-00918-5","DOIUrl":"10.1038/s41428-024-00918-5","url":null,"abstract":"General-purpose petroleum-derived plastic remains in the environment for long periods and has significant impacts on oceans and land. Biodegradable and biomass plastics are being developed around the world as countermeasures. A poly(lactic acid) (PLA)/thermoplastic starch (TPS) blend is a promising ecofriendly alternative to biodegradable plastic made from plants. However, owing to the hydrophilicity of starch and the hydrophobicity of PLA, phase separation occurs between PLA and starch. Furthermore, PLA/TPS blends have poor water resistance because of the presence of starch, limiting their applications. In this study, to improve the affinity of PLA for starch, oligo(lactic acid)-grafted starch (OLAgSt) was synthesized as a compatibilizer for PLA/TPS blends, and the effect of its addition to PLA/TPS blends was evaluated. OLAgSt with different OLA molecular weights and degrees of substitution (DS) were synthesized, and their effects on PLA/TPS were compared. The results indicated that OLAgSt functioned as a good compatibilizer, improving the dispersibility of TPS in PLA with 4 wt% OLAgSt added to PLA/TPS and improving the water resistance. Moreover, the OLA molecular weight of OLAgSt was greater than that of DS. These results are expected to facilitate the development of PLA/TPS applications in the food packaging and biomedical fields. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 10","pages":"905-913"},"PeriodicalIF":2.3,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00918-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141528869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase diagram for the gelation of temperature-responsive and biocompatible poly(oligo ethylene glycol methyl ether methacrylate) polymers in aqueous free-radical polymerization reactions","authors":"Takuma Kureha, Takuto Hirayama, Taichi Nishi","doi":"10.1038/s41428-024-00929-2","DOIUrl":"10.1038/s41428-024-00929-2","url":null,"abstract":"In this study, gel-phase diagrams of temperature-responsive and biocompatible polymers were obtained, and the characteristic gelation behaviors of the polymers were examined. The polymers are based on three oligoethylene glycol methyl ether methacrylate (OEGMA) monomers with different numbers of ethylene oxide (EO) units, i.e., with side chains that differ in length. The gelation thresholds depend on the OEGMA and crosslinker concentrations as well as the side chain length. Long EO side chains fill the polymerization system and reduce the concentration of polymer overlap, resulting in a high ability to occupy the system. Furthermore, the EO side chains may engage in self-crosslinking, i.e., polymers can branch and grow from the side chains depending on their length, resulting in a high bond probability. Based on these unique behavior patterns, gelation occurs more readily as the length of the side chains increases. We also synthesized ultralow crosslinked pOEGMA gels by tuning the gelation conditions; these gels exhibited improved swelling capacity and temperature responsiveness. These results should facilitate the development of a synthesis strategy to control the physical properties and structures of these materials for advanced applications, such as biofilms, actuators, and carriers. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"1017-1029"},"PeriodicalIF":2.3,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00929-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supramolecular methodologies for the assembly of optical microresonators from functional organic materials","authors":"Hiroshi Yamagishi","doi":"10.1038/s41428-024-00925-6","DOIUrl":"10.1038/s41428-024-00925-6","url":null,"abstract":"An optical microresonator is a micrometer-scale object that can confine light inside its body via total internal reflection at the boundary. In addition to well-established applications, including laser oscillators, optical sensors, and quantum memory, 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, which enables the assembly of optical resonators from chemically and biologically functional organic materials in solution. This article reviews our recent progress on the methodologies for making organic optical resonators and their emergent optical properties. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 10","pages":"887-894"},"PeriodicalIF":2.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00925-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141353862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing crystal transitions in low-temperature, low-concentration NaOH solutions to prepare cellulose I and II composite materials","authors":"Yuki Kugo, Takuya Isono, Masashi Fujiwara, Toshifumi Sato, Hirofumi Tani, Tomoki Erata, Kenji Tajima","doi":"10.1038/s41428-024-00928-3","DOIUrl":"10.1038/s41428-024-00928-3","url":null,"abstract":"Cellulose II exhibits exceptional attributes, including flexibility, high stainability, and gloss. However, its strength is lower than that of cellulose I due to reduced crystallinity during the crystal transition. In this study, we devised a novel method to regulate the proportion and distribution of cellulose I and II crystals. This was achieved by employing a low-concentration alkaline solution and liquid nitrogen, resulting in a high-strength composite material that retained the excellent properties of cellulose II. When cellulose powder was immersed in an 8 wt% NaOH solution and quenched with liquid nitrogen, the crystal transition from cellulose I to II occurred outward from the sample periphery to its center. The percentage of cellulose II increased proportionally with treatment time. This technique was extended to cellulose I-rich cotton fibers, facilitating the creation of a composite fiber with cellulose I at the core and cellulose II on the surface. The tensile strength and Young’s modulus of the composite fiber were greater than those of the mercerized cellulose II fiber. Additionally, the elongation at break and toughness of these fibers surpassed those of conventional cotton fibers. This innovative method allows for the preparation of cellulose I and II composite materials with diverse properties. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 10","pages":"939-943"},"PeriodicalIF":2.3,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141354671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of Pd-immobilized porous polymer catalysts via Bayesian optimization","authors":"Xincheng Zhou, Hikaru Matsumoto, Masanori Nagao, Shuji Hironaka, Yoshiko Miura","doi":"10.1038/s41428-024-00923-8","DOIUrl":"10.1038/s41428-024-00923-8","url":null,"abstract":"In this study, a Pd-polymeric porous immobilized catalyst is prepared for the Suzuki–Miyaura coupling reactions by employing a Bayesian optimization method to optimize the catalyst. This research represents the first endeavor to utilize machine learning for the optimization of polymer-immobilized catalysts and provides a novel perspective on utilizing machine learning for the optimization of complex materials. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 9","pages":"865-872"},"PeriodicalIF":2.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00923-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141375975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polymer replica of microcrystalline surface with dual wettability, mimicking a termite wing","authors":"Yuki Hashimoto, Amane Hase, Ayumu Tani, Ryo Nishimura, Yohei Hattori, Hiroyuki Mayama, Satoshi Yokojima, Shinichiro Nakamura, Kingo Uchida","doi":"10.1038/s41428-024-00926-5","DOIUrl":"10.1038/s41428-024-00926-5","url":null,"abstract":"Termite wings are covered with hair shafts and micrasters, which provide it with dual wettability. Although the surface is superhydrophobic for bulk water and large droplets, it is adhesive for microdroplets of water. We mimicked this rough surface by applying a photoinduced crystal growth phenomenon on a photoreactive crystalline surface consisting of two photochromic diarylethene derivatives. This crystalline surface showed dual wettability, but the photoreactive crystalline system was not applicable under daylight. This lack of applicability was apparent because the rough crystalline structures on the surface melted under visible light irradiation. We used soft lithography and transcribed the rough structure of the crystalline film to a stable polycycloolefin polymer (ZEONEX 480) surface. In this case, ultrasonic treatment was indispensable for molding complex structured surfaces. The transcribed surface showed the same characteristics of dual wettability as the crystalline surface. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 9","pages":"847-853"},"PeriodicalIF":2.3,"publicationDate":"2024-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141377085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PJ ZEON Award for outstanding papers in Polymer Journal 2023","authors":"Keiji Tanaka","doi":"10.1038/s41428-024-00905-w","DOIUrl":"10.1038/s41428-024-00905-w","url":null,"abstract":"","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 6","pages":"567-568"},"PeriodicalIF":2.8,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00905-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structure and mechanical properties of biobased polyamide 11 specimens subjected to different heat treatments","authors":"Toyoshi Yoshida, Mei Touji, Hideaki Takagi, Nobutaka Shimizu, Noriyuki Igarashi, Shinichi Sakurai, Makoto Uchida, Yoshihisa Kaneko","doi":"10.1038/s41428-024-00924-7","DOIUrl":"10.1038/s41428-024-00924-7","url":null,"abstract":"The macroscopic mechanical properties of polyamides depend on their microscopic structural properties, such as the crystalline phase, lamellar thickness, and long period, which change depending on the heat treatment conditions. In this study, the relationships between the macroscopic mechanical properties and lamellar structures of polyamide 11 obtained from different heat treatments were investigated. Heat treatments include quench, isothermal, and quench–annealing conditions. Wide-angle X-ray scattering measurements indicated that different crystalline phases formed depending on the heat treatment conditions. Polarized optical microscopy and differential scanning calorimetry revealed spherulite and crystal morphologies that were not spherulite. Small-angle X-ray scattering revealed that the lamellar thickness and long period increased with the heat treatment temperature. With increasing the long period of lamellae, the number of stress transmitters, which are stress transfer factors (entanglements, loop chains, etc.) between lamellae, increases. The lamellar thickness and long period of polyamide 11 were ~1.5 times greater than that of polyamide 6 under similar heat treatment. In uniaxial tensile tests, polyamide 6 specimens heat-treated at high temperatures fractured and did not elongate. Polyamide 11 elongated without fracture. The thick lamellar and long-period structure of polyamide 11 obtained from heat treatments in this study might explain its excellent elongation until the late stage of deformation. 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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 9","pages":"833-845"},"PeriodicalIF":2.3,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supracolloidal step-growth polymerization of isotropic silica nanoparticles: a time-resolved small-angle X-ray scattering study","authors":"Tatsuki Oishi, Ayae Sugawara-Narutaki, Rintaro Takahashi","doi":"10.1038/s41428-024-00922-9","DOIUrl":"10.1038/s41428-024-00922-9","url":null,"abstract":"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.","PeriodicalId":20302,"journal":{"name":"Polymer Journal","volume":"56 11","pages":"1089-1092"},"PeriodicalIF":2.3,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41428-024-00922-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141251819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}