最新刊期
卷 54 ， 期 10 ， 2023
- 摘要：Inspired by the reversible growth of planaria, we develop a class of photo-regulated reversible growing materials. The materials are made from a photolabile inimer (vinyl-oNB-Br) consisting of three functional moieties, i.e., acrylate-based double bond for incorporation within a network, Br group for further visible light-induced grafting polymerization, and o-nitro benzyl (oNB) moiety for UV light-triggered cleavage. This inimer is copolymerized with di(ethylene glycol)ethyl ether acrylate to prepare "seed" elastomers (I-PDEEA). For growth, these seed elastomers are soaked in "nutrient" solutions containing monomer (NIPAAm) and photoinitiator (Mn2(CO)10). The swollen samples are then irradiated by visible light (460 nm), which induces successful polymerization of NIPAAm from the polymer networks to get the grown material (I-PDEEA-PNIPAAm). For degrowth, the grown samples are exposed to UV light (360 nm), under which the oNB undergoes photocleavage reaction to free the grafted PNIPAAm chains. The samples shrink when these free chains are extracted from the polymer network, showing a degrowing effect. The degrowth can be directly conducted in a DMF solution, leading to direct contraction. Our study indicates that the network topologies and the neat mass change in growth and degrowth can be regulated by the inimer fractions in the seed polymer networks and the concentrations of NIPAAm in nutrient solutions. This reversible growth method allows post-modifying crosslinked polymers in mass, size, bulk, and mechanical properties. For example, the growth of PNIPAAm can lead to a neat increase of up to 0.55 mg/cm3 and tune the hydrophobic matrices to be hydrophilic. Moreover, the materials are stiffened and toughened (toughness: from 0.15 MJ/m3 to 1.18 MJ/m3). After degrowth, the samples return to hydrophobic, soft, and brittle states (toughness: 0.25 MJ/m3). These results indicate that photo-regulated reversible growth is a facile, efficient method for post-regulating the properties of crosslinked polymer materials in situ.关键词：Reversible growth;Photo-regulated;Crosslinked polymers;Mechanical property
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发布时间：2023-09-25
Rapid Communication
- 摘要：Protein-polymer conjugates are an important class of long-acting proteins, and they have been applied in the diagnosis and treatment of various serious diseases. However, due to the shortcomings of non-specificity, low yield, and potential immunogenicity in current PEGylation method, exploring new, efficient, and mild methods for preparing protein-polymer conjugates with well-defined structures and controllable functions is an important scientific issue in this field. In recent years, our research group and colleagues integrated the two technologies of "site-specific protein modification" and "in situ controlled polymerization", proposing the concept of "site specific in situ controlled polymerization (SICP)" to replace traditional PEGylation technology, and made great progress in biomedical applications. The research progress of SICP method is introduced in detail in this review, which mainly focuses on the background of developing SICP methods, site-specific protein modification, in situ controlled polymerization, and its application in the biomedical fields. In the methodology part, the N-terminal site-specific modification method based on 2,6-pyridinedialdehyde and the in situ controllable polymerization method mediated by atom transfer radical polymerization (ATRP) are emphasized. In the biomedical application part, the applications of anti-tumor therapy, antibacterial therapy, and in vitro diagnosis are discussed, with a focus on the application of three different types of protein-polymer conjugates in anti-tumor therapy: self-assembled protein-polymer conjugates promoting protein pharmacokinetics, responsive protein-polymer conjugates enhancing tumor retention, and functional protein-polymer conjugates enhancing targeting efficiency and tumor permeability. Finally, brief summary and outlook on the future directions of developing SICP method are also discussed.关键词：Protein-polymer conjugates;Site-specific in situ controlled polymerization;Atom transfer radical polymerization;anti-tumor therapy;Stimuli-responsiveness
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发布时间：2023-09-25 - 摘要：CO2-responsive polymers are a class of polymers that can respond to CO2 gases and solutions. The reaction with CO2 changes the properties of the polymer such as hydrophobicity and charge. By introducing argon, nitrogen and air, or by slightly heating, CO2 can be removed and the properties of the polymer and composite material can be fully or partially restored. This review summarizes the recent development of CO2-responsive polymers and composites, introduces different types of responsive polymers from chemical structures and responsive groups, including amidines, tertiary amines, guanidines and imidazoles, and summarizes the monomers of common CO2-responsive polymers. The different functions of CO2-responsive polymers are introduced. Different properties of vesicles, spherical micelles and composite assemblies and other morphologies are discussed from the viewpoint of assemblies, while the construction and effects of emulsions, aerogels and hydrogels, functional surfaces and nanofiber membranes, organic-inorganic hybrid materials and composites, and fluorescence sensing and monitoring systems are summarized progressively. Finally, the problems that need to be explored and optimized in this field are discussed, and the future development direction is foreseen.关键词：CO2-switchable;Environmental response;Polymer assemblies;Hydrophobic and hydrophilic performance;Sensor
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发布时间：2023-09-25
Feature Article
- 摘要：Recently, biodegradable polymer materials have drawn much attention due to their environmental friendliness. Among them, natural polyhydroxyalkanoates (PHAs), a type of isotactic polyesters produced by microorganisms, exhibit excellent biocompatibility and biodegradability, and thus are promising alternatives to petroleum-based plastics. Chemical synthesis of PHAs possesses enormous application value due to their high synthesis efficiency, great controllability and easy control of product quality. Since the stereoregularity and crystallinity of PHAs strongly affects their thermal and mechanical properties as well as degradation rates, controlling the stereoregularity and/or crystalline PHAs is a key and also challenging issue in their synthesis process. This review provides a comprehensive overview of the advancements in the chemical synthesis of stereoregular and/or crystalline PHAs in the last 60 years from the perspective of monomer classification. It covers the stereoselective ring-opening (co-)polymerization of four-membered lactones (e.g., β-butyrolactone (β-BL) and its derivatives (BPL, MLA), β-propiolactones with different α-, β-, and α,β-substitutions), eight-membered lactones (β-BL's dimer, 8DL), twelve-membered lactone (β-BL's trimer, TBL) and epoxides/CO. The review places particular emphasis on the effects of different catalyst systems on stereoselectivity, and summarizes the mechanical and thermal properties of the resulting polymers. Furthermore, it briefly touches upon the degradation and recycling strategies of PHAs, followed by an outlook on the approaches for achieving stereoselective controlled synthesis of PHAs.关键词：Biodegradable polymers;Polyhydroxyalkanoates;Crystalline polymers;Stereoselective polymerization;Ring-opening polymerization
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发布时间：2023-09-25 - 摘要：Due to their unique supersoft, superelastic, quick strain hardening, and other fascinating viscoelastic features, cylindrical side-chain polymer systems, such as bottlebrush polymers, have gained significant interest recently. In this mini-review, we intend to summarize the relevant research progresses. Several typical side-chain polymers that demonstrate the structure of the single-chain supramolecular columns, including bottlebrushes, dendronized polymers and mesogen-jacketed liquid crystalline polymers, are introduced along with their linear viscoelasticity. Furthermore, the features of multi-chain supramolecular columns are illustrated by using the self-assembly of wedge-shaped side-chain polymers as the example. After a brief overview of the functional applications of cylindrical side-chain polymer systems, we give some comments on the obstacles and challenges in this research field. Even though the physical mechanisms underlying the complex relaxation behavior of cylindrical side-chain polymers caused by entanglement and microphase separation are still not fully understood, research on these polymers will offer fresh perspectives and a theoretical foundation for creating brand-new viscoelastic materials.关键词：Side-chain polymers;Cylindrical structure;Viscoelasticity;Entanglement;Functional applications
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发布时间：2023-09-25
Review
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Preparation of Imide-based Microporous Organic Polymers by Alternating Free Radical Copolymerization 增强出版
摘要：Hyper-crosslinked organic microporous polymers (HOMPs) are constructed by connecting aromatic building blocks with short carbon bridges, without lab-cost work and expensive catalysts in comparison with metal organic frameworks (MOFs), covalent organic frameworks (COFs) and conjugated microporous polymers (CMPs) counterparts. Usually, hyper-cross-linking processes via Friedel-Craft alkylation reaction produce a large number of corrosive gases during reaction process and waste Lewis acid catalysts after polymerization. In order to achieve greener preparation protocol, in this study, three bismaleimide monomers (m-PBM, p-PBM and DBM) and four vinyl ethers (DOE, DVE, TVE and TAE) are employed as building blocks for radical polymerization, and twelve cross-linked porous polyimides have been successfully prepared. Thanks to the opposite polarity structure, the alternating copolymerization between the above donor and acceptor monomers is very likely to occur due to the formation of charge-transfer complexes, endowing the obtained polymers with predictable and controllable molecular architectures. In addition, only trace amounts of initiator are required for radical copolymerization and no by-products are generated, which greatly simplify the post-processing of the polymers. The highly polar imine rings and abundant microporous structure provide the products good thermal stability, high specific surface area (591 m2/g), and excellent CO2/N2 selectivity (74.38). This study benefits for exploring new building blocks to construct microporous polymers and probe their practical applications.关键词：Radical alternating copolymerization;Porous polyimides;Hyper-crosslinked polymers;Carbon dioxide (CO2) capture and storage- 173
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发布时间：2023-09-25 - 摘要：Polymeric "tailor-made" inhibitors can accomplish excellent resolution performance with low adding amount. However, its large-scale application is limited by the tedious "chiral monomer to polymer" synthetic route. In a previous work, we have developed an efficient modular strategy of constructing "tailor-made" supramolecular additives by combining achiral poly(vinylpyridine) and a variety of small chiral molecules through non-covalent interactions. In order to expand the scope of the modular strategy, in this work, we choose the cheap and commercially available polystyrene sulfonic acid as platform macromolecules, and small chiral molecules with primary amine groups or guanidine groups as the side groups to prepare "tailor -made" inhibitors efficiently. Benefiting from the easy preparation, the rapid structure screening and efficient optimization of the polymeric additives have been achieved. It has been proven that additives prepared using this method can be used in water, methanol, isopropanol, and acetone with good performance for the resolution of amino acids, nimodipine, guaifenesin, and synthetic intermediate hydrobenzoin and methyl 2,3-dihydrobenzo[b][1,4]dioxine-2-carboxylate. Combined with molecular docking simulation, effective suggestions are put forward for the rational design of "tailor-made" additives. We recommend that a batch of alternative small molecules could be selected based on structural similarities, and the crystallization resolution should be performed using the molecule with the smallest binding energy value in the molecular docking calculation of conglomerates crystal plane. Therefore, the number of trial and error and the cost of crystallization additive screening are reduced, improving the effectiveness of inhibitor structure design greatly.关键词：Crystallization resolution;Tailor-made additives;Enantioselectivity;Modular preparation;Chiral medicine
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发布时间：2023-09-25 - 摘要：Polydithiocarbamates are a group of promising functional polymer materials with unique mechanical property and dynamic reversible property, however, the exploration of structures and functionalities of these polymers are limited by the synthetic approaches. In this work, considering the problems regarding the side reactions and low efficiency in the reaction of elemental sulfur, isocyanide, and thiol, one-pot two-step tandem strategy, organic bases, and reaction temperature were carefully designed to improve the efficiency and selectivity of the reaction. The organic base-catalyzed multicomponent tandem polymerizations of elemental sulfur, diisocyanides and dithiols were developed, with N,N-diisopropylethylamine as the base in DMSO, affording polydithiocarbamates with Mns of up to 1.77×104 g/mol. The polymerization was mild and convenient, which could be applied to both aliphatic and aromatic isocyanides, to synthesize polydithiocarbamates with different structures. These polymers possessed good thermal stability, and could be degraded to oligomers in the presence of thiol. The multicomponent tandem polymerizations could provide a mild and convenient synthetic approach for polydithiocarbamates, which may accelerate the development of these sulfur-containing degradable polymer materials.关键词：Elemental sulfur;Multicomponent tandem polymerization;Polydithiocarbamates;Degradable polymers
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发布时间：2023-09-25 - 摘要：Zinc porphyrin-based covalent organic framework (COF) DhaTph-Zn-COF and conjugated microporous polymer (CMP) DhaTph-Zn-CMP as heterogeneous photocatalysts were prepared to activate photoinduced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization under broad-range wavelengths. They could efficiently transfer electrons to chain transfer agents to synthesize polyacrylamides and polyacrylates with controllable molecular weight, narrow molecular weight distribution (<1.20), and high chain-end fidelity. The apparent polymerization rate constants were 0.0522 h-1 and 0.0621 h-1 for polymerization of N,N-dimethacrylamide with 2.5 mg/mL DhaTph-Zn-COF or DhaTph-Zn-CMP, respectively, under yellow light irradiation. The different stacking patterns and the degree of conjugation for the freshly prepared COF and CMP materials affected structure and photophysical properties, such as crystallinity, specific surface area, band gap, fluorescence lifetime, charge transfer resistance, etc. Although DhaTph-Zn-COF had an ordered stacking with better electron transfer properties, their similar catalytic properties indicated that the stacking patterns were not the primary factor to enhance the performance of photocatalysts. Meanwhile, the difference in photocatalytic polymerization of metalloporphyrin-based COFs displayed that a building block (zinc porphyrin) with high photocatalytic efficiency in a homogenous system is vital to the design of the heterogeneous photocatalysts for polymerization. Besides, the stability of photocatalysts directly affected the efficiency of catalytic cycles. Compared with DhaTph-Zn-COF, the amorphous DhaTph-Zn-CMP showed more robust chemical stability after several rounds of polymerization and could be used at least five times. The reduced efficiency of DhaTph-Zn-COF after recycling resulted from the loss of active components. The scanning electron microscopy (SEM) revealed the morphological difference between the COF and CMP photocatalysts. Better stability could be credited to the tight-packed particles formed by the disorderly stacked structure, which avoided the destruction by external factors such as monomers, solvents, and stir. This work provides insights into the design factors of heterogeneous POP photocatalysts for photopolymerization and promotes the development of efficient semiconductors and heterogeneous photocatalysts.关键词：Covalent organic frameworks;Conjugated microporous polymers;Heterogeneous photocatalysts;Photoinduced electron transfer reversible addition-fragmentation chain transfer polymerization
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发布时间：2023-09-25 - 摘要：Most of polymeric vesicles not only lack the specific recognitions of immune cells and the bioactivities of adjuvants to trigger efficient adaptive immunities, but also lack good biodegradability and biocompatibility, which hamper the immunotherapy applications. To develop biodegradable polymer nano-carries with both immune activity and cell-targeting, three kinds of glycopolypeptide nanovesicles constructed by linear polypeptide-glycodendrimer copolymers were synthesized and the applications in co-delivery of protein antigens and agonists were studied. The glycopolypeptide nanovesicles (PNLys-4Man, PNLys-4Gal, PNLys-4Glu) were fabricated in aqueous solution by a dialysis method, which had similar sugar density, hydrodynamic size of about 100 nm and Zeta potential of about 35 mV, and present sugar-dependent recognition with lectins. Those glycopolypeptide vesicles could co-load ovalbumin (OVA) and imiquimote (R837) in phosphate buffer solution (pH=7.4) to give a hydrodynamic size of about 75 nm, and the loading capacity of OVA and R837 was about 7.5% and about 1.3%, respectively. Moreover, those vesicles showed sugar-dependent adjuvant effects of promoting dendritic cell (DCs) maturation, in which the mannosylated ones enhanced the maturation of DCs to 34.6% compared to the galactosylated ones of 29.4% and the glucosylated ones of 27.7%. These data evidence that the mannosylated glycopolypeptide vesicles exhibited a cell-targeting enhanced immunity. Furthermore, the mannosylated nanovesicles activated the maturation of DCs to secret costimulatory molecules of IL-6 and TNF-α, and their levels were respectively enhanced by 19.5% and 20.3% than the galactosylated ones, and by 17.7% and 37.4% than the glucosylated ones, further confirming the sugar-dependent maturation effect on DCs. Especially, UV light triggered intracellular rapid co-release of OVA and R837, and the levels of IL-6 and TNF-α remarkably enhanced by 2.19-fold and 1.82-fold, demonstrating that OVA antigen and R837 agonist possessed synergistic effect to promote DCs maturation and induce strong immune response. Consequently, this work opens a new avenue to construct the immune cells-targeted biodegradable nanocarriers for delivering antigens and agonists to fight against infectious diseases and cancers.关键词：Glycopolypeptide;nanovesicle;protein delivery;agonist;immune adjuvant
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发布时间：2023-09-25 - 摘要：The self-assembly behavior of the supramolecular complex system of polydimethylsiloxane-b-poly(2-vinylpyridine) (PDMS-b-P2VP, DV) and 4-hydroxyazobenzene (Azo) based on hydrogen bonding interaction was investigated. Supramolecular block copolymer was prepared by solution blending method. The interaction between Azo molecules and PDMS-b-P2VP and the effect of Azo molecules content on the self-assembly behavior of the system were investigated by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM). The results demonstrate that Azo can effectively form hydrogen bond with pyridine group in PDMS-b-P2VP. The glass transition temperature of P2VP block decreased with the increase of the molar ratio (x) of Azo/2VP. With x value changed from 0 to 0.5, the supramolecular block copolymers presented lamellae (LAM), hexagonally packed cylinder (HEX), and body centered cubic (BCC) structures. However, when x is higher than 0.5, the self-aggregation of Azo occurred and the phase-separated nanostructure becomes disordered. Our future work will focus on the light-responsive structure regulation of these supramolecular block copolymers.关键词：Polydimethylsiloxane;Poly(2-vinylpyridine);Hydrogen bond;Self-assembly;Supramolecular block copolymer
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发布时间：2023-09-25 - 摘要：A new type of supramolecular mesogen-jacketed liquid crystalline polymer (MJLCP) was constructed by hydrogen bonding with poly(4-vinyl pyridine) (P4VP) as the hydrogen-bonding acceptor and carboxyl-containing molecules as hydrogen-bonding donors. The formation of hydrogen bonds was proven by Fourier-transform infrared spectroscopy (FTIR) and wide-angle X-ray scattering, and the effect of molecular structures on the phase behaviors of supramolecular MJLCPs was systematically studied. The results showed that because the "jacketing" effect of hydrogen-bonding donor molecules with only one (8MP) and three benzene rings (4TP and 6TP) and relatively short alkyl-chain tails was not strong enough when they were complexed with P4VP, the complexes P4VP(4TP)x, P4VP(6TP)x, and P4VP(8MP)x are disordered at a molar complexing ratio x (between the donor and the acceptor) of 1.0. The four types of complexes P4VP(8TP)x, P4VP(10TP)x, P4VP(12MP)x, and P4VP(16MP)x undergo a transition from an disordered structure to the smectic (Sm) phase when the complexing ratio increases, and the minimum ratio for the appearance of liquid crystalline phases gradually decreases when the length of alkyl-chain tails and the rigidity of the hydrogen-bonding donor increase. Because of the high rigidity of the hydrogen-bonding donor and its long alkyl-chain tails, the P4VP(12TP)x undergoes a phase transition from disordered to the Sm phase and then to a hexagonal columnar (Colh) phase with the increase in the complexing ratio. However, if the size of the hydrogen-bonding donor molecule is too large, the formation of hydrogen bonds would be hindered, and macroscopic phase separation occurs in P4VP(8PP)x even when the complexing ratio is very low. The use of hydrogen bonding greatly simplifies the construction of MJLCPs. The liquid crystalline phase can be flexibly regulated by controlling the structure of small molecules and the complexing ratio, which provides a new idea for the structural design of MJLCPs with complex structures.关键词：Mesogen-jacketed liquid crystalline polymer;Hydrogen bonding;Supramolecular liquid crystal;Self-assembly
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发布时间：2023-09-25 - 摘要：A class of polystyrene liquid crystalline polymer PS-n (n=2, 6, 8, 10, 12) with unconventional side chain structure was designed and synthesized. The influence of flexible spacer on the supramolecular columnar liquid crystalline phase formation was systematically studied. All polymers exhibit enantiotropic thermotropic liquid crystalline phase behaviour. When the flexible spacer is short (n≤6), the polymer forms a two-dimensional supramolecular ordered oblique columnar (Colob) phase structure, which results from the periodic fluctuation of the one-dimensional layered structure caused by the ortho substitution of two biphenyl mesogens per side chain. As the spacer length increases (n≥8), the polymer can exhibit two Colob phases with different lattice parameters at different temperatures. The Colob(I) phase with relatively small lattice parameter appeared near room temperature shows a characteristic undulated lamellar structure with oblique symmetry. With the increase of temperature, the polymer enters a higher ordered Colob(Ⅱ) phase with larger lattice parameter, showing the specific self-assembly behaviour at high temperature. When further increasing temperature, all polymers exhibit Colob to lamellar phase transition before entering isotropic state. The existence of long spacer length tends to promote the self-organization behaviour of side chain, which makes the appearance of highly ordered mesophase. Due to the parallel orientation of columnar structure, the fingerprint-like morphology can be found on the surface of thermal annealed PS-n thin film, and the macroscopic orientation can occur along the shear direction under shear induction.关键词：Liquid crystalline polymer;Supramolecular columnar phase;Polymer thin film;Small angle X-ray scattering
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发布时间：2023-09-25 - 摘要：In recent years, polyimide has shown great application prospects in the fields of cover sheet for space solar cell due to its outstanding mechanical property, excellent thermal stability, light weight, easy processing and other properties. However, the transparency and irradiation-resistant properties of optically transparent polyimides need to be further improved. Herein, a new transparent polyimide film is prepared by the copolymerization of 2,2'-bis(trifluoromethyl)diaminobenzene, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride and doping with fluorine-containing ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. Magnesium fluoride and silicon dioxide antireflective films are successively coated on the surface of the polyimide film by electron beam evaporation technology, and a novel silicon dioxide/magnesium fluoride/transparent polyimide (SiO2/MgF2/CPI) composite film that can be used as cover sheet for solar cell is obtained. The investigation of the thermal, optical, mechanical and irradiation-resistant properties shows that the initial thermal decomposition temperature of this SiO2/MgF2/CPI composite film is 394.8 ℃, the tensile strength reaches 65.81 MPa, and the light transmittance at 550 nm is as high as 93.43%. After electron irradiation with electron energy of 50 keV and irradiation fluences of 4×1014, 2×1015 and 4×1015 e/cm2, the thermal stability, light transmittance and mechanical properties of the SiO2/MgF2/CPI composite film have no significant decrease, showing excellent irradiation-resistant property and good application prospect in solar cell cover sheets of space vehicles.关键词：Transparent polyimide;Solar cell cover;Antireflective film;High transmittance;Irradiation-resistant
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发布时间：2023-09-25 - 摘要：In order to understand the effects of N-substitution on the water/salt transport behavior of polybenzimidazole (PBI), in this work, considering that the N―H bond on the imidazole ring in PBI is reactive, three comparable N-substituted groups (p-benzoyl, p-benzenesulfonyl, and butyl) were selected to react with the N―H group, and the physical and chemical properties of PBI after N-substitution were investigated by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and surface zeta potential, and solution-diffusion theory to investigate the effects of different N-substituted groups on the water/salt transport behavior of PBI. The results show that the N-substitution modification leads to the reduction of interactions between polymer chains and the increase of polymer molecular chain spacing, while the electronegativity of the membrane surface is enhanced. At the same time, the N-substitution modification results in larger free volume cavities between PBI molecular chains, which increase the water transport channels, and increases the accessibility of hydrophilic groups and decreases the content of free water; thus, it can improve the water/salt solubility, diffusivity and permeability selectivity of PBI effectively. Among them, p-biphenylsulfonyl whose diffusive water permeability coefficient is 30 times higher compared with PBI, exhibits the most excellent water/salt transport properties. It provides an understanding of the effect of polymer modification on the water/salt transport properties of PBI, and also provides a reference for future molecular structure design of high performance polymers oriented to desalination.关键词：Polybenzimidazole;N-substitution;Solution-diffusion theory;Water/salt transport;Desalination
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发布时间：2023-09-25 - 摘要：Alkaline anion exchange membrane (AEMs) is an important component in the preparation of alkaline fuel cells, which should have high ionic conductivity and alkaline stability. In this work, we present a rationally designed block copolymer of polynorbornene as the backbone of AEMs, which maintains excellent stability in strong alkaline media. Furthermore, ionic conducting fluorophenyl quaternary ammonium salt and non-conducting triethyl silicon group are introduced in side chains to attain tunable polymer structures. Due to the hydrophilic and hydrophobic interactions, channels are formed in the polymer membrane for the transfer of hydroxide. In addition, in order to achieve nondestructive detection of AEMs, tetraphenyl ethylene with aggregation-induced luminescence, for the first time, is introduced as crosslinking monomer to prepare block copolymers via ring-opening metathesis polymerization with Grubbs II as catalyst. The copolymers exhibit excellent thermostability, mechanical properties and alkali resistance. The maximum stress and elongation at break of PNB-NOHPhF1-3Si-TPE are σb = 36.56 MPa and δ=16.92%, respectively, and the 5% weight lost temperature is over 250 ℃. Compared with the reported AEMs with single quaternary ammonium salt, the block copolymers PNB-NOHPhF1-3Si-TPE show better alkali resistance and higher conductivity of 24 mS/cm at 80 ℃. The ion channels formed by microphase separation can be observed with scanning electron microscopy (SEM) by scanning the polymer cross section. Under 365 nm UV-light, the film emits uniform green fluorescence. Because of the lack of fluorescence at the damage sites, the integrity of film is non-destructively visualized.关键词：Alkaline anion exchange membrane;Polynorbornene;Ring-opening metathesis polymerization;Microphase separation;Aggregation-induced emission
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发布时间：2023-09-25 - 摘要：The mass production of multifunctional integrated fiber electrodes is the foundation for achieving large-scale wearable applications of fiber or fabric-based electronic devices. Based on the flexible, functional and molecular structure adjustable characteristics of polymer semiconductor materials, a method for segmental in situ synthesis of polyaniline functional layers on long fiber surfaces has been put forward in this work. And then, coated with conductive carbon materials, this allows for the successful continuous preparation of segmental multifunctional integrated fiber electrodes. By modifying the fiber substrate with oxidative treatment, the affinity of the fiber substrate to the aniline substrate can be enhanced, which overcomes the problem of polymer functional layer boundary diffusion caused by capillary wetting or detachment. On this basis, according to a kind of novel textile-based circuit design, a textile-structured integrated circuit module has been developed, which can simultaneously realize continuous monitoring of human sweat pH value, health status judgment, and early warning. Co-woven with the fiber-structured Zn/MnO2 batteries, as well as integrated with mini wireless chips, light-emitting diodes, etc., this integrated circuit textile enables consecutive human body wireless monitoring and timely emergency warning for abnormal situations, demonstrating its potential application in future wearable AI hardware.关键词：Polymer semiconductor;Polyaniline;Segmental in situ synthesis;Multifunctional integrated fiber electrodes;Wearable
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发布时间：2023-09-25 -
Ultralong Organic Room Temperature Phosphorescence Polymer Films Based on 9
H -Dibenzo[a,c]carbazole 增强出版摘要：Benzocarbazole and its derivatives have excellent ultralong organic room temperature phosphorescence (RTP) properties. Polymer films can help benzocarbazole molecules achieve better phosphorescence performance. In this paper, a new organic phosphorescence unit named 9H-dibenzo[a,c]carbazole (CzNPh) is designed and synthesized, and thin films are prepared by using different polymer materials. Compared with the doped poly(methyl methacrylate) (PMMA) films, the doped poly(vinyl alcohol) (PVA) films of CzNPh have higher phosphorescence intensity, longer phosphorescence lifetime (τ = 2.12 s), higher phosphorescence quantum yield (Φp=7.95%). Radical ions participate in formation of charge separation states and are involved in the emitting process of ultralong phosphorescence. Rigid environment in PVA films and enhanced interactions between CzNPh and PVA facilitate formation of charge separation states and reduce non-radiative transition caused by molecular motion and the quenching of triplet excitons by oxygen. In addition, CzNPh@PVA films can also realize the stimulation response to water because water can damage the interactions between CzNPh and PVA, so CzNPh@PVA films can be applied in information encryption, humidity detection, etc.关键词：9H-Dibenzo[a;c]carbazole;Room-temperature ultralong phosphorescence;Poly(vinyl alcohol) polymer film;Free radical- 154
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发布时间：2023-09-25 - 摘要：A highly carboxylated sponge monolithic adsorbent material (PVA/BTCA porous material) was prepared using SiO2 nanofibers as a three-dimensional structural rigid support framework and an esterified cross-linking reactant of poly(vinyl alcohol) (PVA)/butane tetracarboxylic acid (BTCA) as a functional organic binder. As a kind of adsorption material, it is proven that PVA/BTCA material has good structural stability under water by underwater cyclic compression test. The highly carboxylated and high porosity of the PVA/BTCA porous material provided the basis for protein adsorption, which could selectively adsorb positively charged proteins. Using lysozyme as the main model protein, the maximum adsorption of PVA/BTCA porous material for lysozyme at pH=7 was 1342.3 mg/g. The isothermal adsorption model of PVA/BTCA porous material for the adsorption of lysozyme is in close agreement with the Freundlich adsorption model. The excellent mechanical stability and chemical structural stability confer reusability to the PVA/BTCA porous material. This work is expected to provide a new separation material for protein separation.关键词：Lysozyme;three-dimensional material;Adsorption;Poly(vinyl alcohol)
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发布时间：2023-09-25
Research Article
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