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Highly active organocatalyst from a trivalent phosphazenium salt for ring-opening copolymerization of epoxides and cyclic anhydrides enhanced by hydrogen bonding interactions

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Science China chemistry 2024年第9期67卷 3111-3120页

作者： Chunhuan Jiang Junqi Wang Xiaoyu Liu Xiaoxia You Ronglin Zhong Chuanli Ren Zhibo Li Key Laboratory of Biobased polymer Materials Shandong Provincial Education DepartmentCollege of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China Laboratory of Theoretical and Computational chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130012China

It is highly desirable to develop simple organocatalysts for the controlled ring-opening alternating copolymerization(ROAC)of epoxides and cyclic anhydrides,leading to high molecular weight ***,a phosphazenium salt,namely tri[tris(dimethylamino)phosphoranylidenamino]phosphonium chloride(P_(4)^(+)Cl^(-)),is developed as a catalyst for the ROAC of epoxides and cyclic ***,the combination of P_(4)^(+)Cl^(-)with a protonic initiator,such as 1,4-benzenedimethanol(BDM)exhibited high efficiency in the copolymerization of propylene oxide(PO)and phthalic anhydride(PA).This led to the production of polyester with an exceptional high molecular weight(M_n)of up to 126 k Da,which represented a rare example of poly(PO-alt-PA)with Mnsurpassing 100 k *** that the core P atom is trivalent status and the tris[tris(dimethylamino)]phosphoranyl group will share one proton in the P_(4)^(+)Cl^(-)*** combined with protonic species,the P_(4)^(+)Cl^(-)will not only serve as a proton acceptor but also as a hydrogen bonding donor for the cyclic ***,it was assumed that the P_(4)^(+)plus proton served dual role in mimic of base/urea pair to effectively catalyze ROAC,which was supported by density functional theory(DFT)calculations.

关键词： ring-opening copolymerization organocatalyst epoxides cyclic anhydrides phosphazenium salt

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A low-swelling hydrogel as a multirole sealant for efficient dural defect sealing and prevention of postoperative adhesion

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National Science Review 2024年第6期11卷 294-307页

作者： Xueliang Cheng Zhen Zhang Hui Ren Zheng Zou Yu Zhang Yang Qu Xuesi Chen Jianwu Zhao Chaoliang He CAS Key Laboratory of polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences department of Orthopedics The Second Norman Bethune Hospital of Jilin University School of Applied chemistry and Engineering University of Science and Technology of China

Dural defects and subsequent complications, including cerebrospinal fluid（CSF） leakage, are common in both spine surgery and neurosurgery, and existing clinical treatments are still unsatisfactory. In this study, a tissue-adhesive and low-swelling hydrogel sealant comprising gelatin and o-phthalaldehyde（OPA）-terminated 4-armed poly（ethylene glycol）(4aPEG-OPA) is developed via the OPA/amine condensation reaction. The hydrogel shows an adhesive strength of 79.9 ± 12.0 k Pa on porcine casing and a burst pressure of 208.0 ± 38.0 cm H2O. The hydrogel exhibits a low swelling ratio at physiological conditions, avoiding nerve compression in the limited spinal and intracranial spaces. In rat and rabbit models of lumbar and cerebral dural defects, the 4aPEG-OPA/gelatin hydrogel achieves excellent performance in dural defect sealing and preventing CSF leakage. Moreover, local inflammation, epidural fibrosis and postoperative adhesion in the defect areas are markedly reduced. Thus, these findings establish the strong potential of the hydrogel sealant for the effective watertight closure of dural defects.

关键词： hydrogel sealant watertight closure low swelling o-phthalaldehyde chemistry dural sealing

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Cellulose-MXene composites: New platforms with outstanding multifunctional characteristics

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Journal of Bioresources and Bioproducts 2024年第3期9卷 243-245页

作者： Farzad Seidi Wensi Jiang Zhaochuan Yu Chao Deng Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials Nanjing Forestry UniversityNanjing 210037China Macromolecular chemistry and bavarian polymer institute University of BayreuthBayreuth 95440Germany

The progress of society has caused a quick rise in the requirement for materials with superior *** composite materials demonstrate exceptional performance due to the synergistic effects resulting from the combination of unique properties exhibited by their constituent *** advantageous characteristic enables these materials to leverage the collective strengths of each component,leading to their outstanding *** leveraging the strengths of each individual component,the shortcomings can be overcome and the strong points can be shared effectively.

关键词： composites MXene composite

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Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-Hui Tang Na Zhang Wei Bao Wei Jiang Yuan Lin Zhao-Hui Su State Key Laboratory of polymer Physics and chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

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Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-Tian Zhang Ming-Xin Niu Qi Zhang Chen-Yang Hu Xuan Pang Key Laboratory of polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

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Facile synthesis of accordion-like porous carbon from waste PET bottles-based MIL-53(Al) and its application for high-performance Zn-ion capacitor

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Green Energy & Environment 2024年第7期9卷 1138-1150页

作者： Jiaxin Li Shuai Zhang Yumeng Hua Yichao Lin Xin Wen Ewa Mijowska Tao Tang Xuecheng Chen Rodney S.Ruoff Faculty of Chemical Technology and Engineering West Pomeranian University of Technology Key State Key Laboratory of polymer Physics and chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Safety Engineering China University of Mining and Technology institute of Advanced Electrical Materials Qingdao University of Science and Technology institute for Basic Science Center for Multiple Dimensional Carbon Materials department of chemistry Ulsan National Institute of Science and Technology (UNIST) department of Materials Science and Engineering Ulsan National Institute of Science and Technology (UNIST) School of Energy and Chemical Engineering Ulsan National Institute of Science and Technology (UNIST)

It is of great scientific and economic value to recycle waste poly（ethylene terephthalate）(PET) into high-value PET-based metal organic frameworks（MOFs） and further convert it into porous carbon for green energy storage applications. In the present study, a facile and costeffective hydrothermal process was developed to direct recycle waste PET bottles into MIL-53（Al） with a 100% conversation, then the MOFderived porous carbon was assembled into electrodes for high-performance supercapacitors. The results indicated that the as-synthesized carbon exhibited high SSA of 1712 m2g-1and unique accordion-like structure with hierarchical porosity. Benefit to these advantageous characters, the assembled three-electrode supercapacitor displayed high specific capacitances of 391 F g-1at the current density of 0.5 A g-1and good rate capability of 73.6% capacitance retention at 20 A g-1in 6 mol L-1KOH electrolyte. Furthermore, the assembled zinc ion capacitor still revealed outstanding capacitance of 335 F g-1at 0.1 A g-1, excellent cycling stability of 92.2% capacitance retention after 10 000 cycles and ultra-high energy density of 150.3 Wh kg-1at power density of 90 W kg-1in 3 mol L-1ZnSO4electrolyte. It is believed that the current work provides a facile and effective strategy to recycle PET waste into high-valuable MOF, and further expands the applications of MOF-derived carbons for high-performance energy storage devices, so it is conducive to both pollution alleviation and sustainable economic development.

关键词： PET Recycling Porous carbon Supercapacitor Energy storage

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Synergistic enhancement of ultrasound therapy for tumors using hypoxia-activated 6-diazo-5-oxo-L-norleucine(DON)prodrug nanoparticles

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Nano Research 2024年第7期17卷 6323-6331页

作者： Mengfei Zheng Zhilin Liu Hang Xu Daping Ye Linjie Cui Chenguang Yang Lili Ma Kun Wang Kazuo Sakurai Zhaohui Tang Key Laboratory of polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Jilin Biomedical polymers Engineering Laboratory Changchun 130022China department of chemistry and Biochemistry The University of Kitakyushu1-1 HibikinoKitakyushu 808-0135Japan

Ultrasound(US)has been applied in clinical practice for its non-invasive and high ***,it is difficult to achieve a satisfactory anti-tumor effect with US ***,the use of US therapy alone can exacerbate tumor *** this study,we prepared hypoxia-activated 6-diazo-5-oxo-L-norleucine(DON)prodrug nanoparticles(HDON-NPs)to improve US therapeutic *** an H22 murine liver cancer model,US therapy selectively disrupted tumor blood vessels,leading to increased tumor hypoxia and a 1.67-fold increase in the expression of nitroreductase(NTR).The combination therapy of US and HDON-NPs demonstrated a synergistic effect,resulting in a tumor suppression rate(TSR)of 90.2%±6.4%,which was 5.93-fold higher than that of US therapy *** combined treatment selectively blocked the glutamine metabolism of the tumor cells while simultaneously activating the T cells in the tumor microenvironment,thereby exerting a robust anti-tumor effect.

关键词： ultrasound therapy hypoxia-activated prodrug nanoparticles 6-diazo-5-oxo-L-norleucine(DON) glutamine antagonist starvation therapy

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Tunable Phase Structure of Side-chain Liquid Crystalline polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng Liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang Ruo-Chen Lan College of chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

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Recent progress and future research directions for electrochromic zinc-ion batteries

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Journal of Energy chemistry 2024年第3期90卷 220-232,I0007页

作者： Tae Gwang Yun Byungil Hwang Jun Young Cheong department of Molecular Science and Technology Ajou UniversitySuwon 16499Republic of Korea School of Integrative Engineering Chung-Ang UniversitySeoul 06974Republic of Korea bavarian Center for Battery Technology(Bay Batt)and department of chemistry University of Bayreuth95447 BayreuthGermany

In recent times,future energy storage systems demand a multitude of functionalities beyond their traditional energy storage *** line with this technological shift,there is active research and development of electrochromic-energy storage systems designed to visualize electrochemical charging and discharging *** conventional electrochromic-energy storage devices primarily integrated supercapacitors,known for their high power density,to enable rapid color ***,the low energy density of supercapacitors restricts overall energy storage capacity,acting as a significant barrier to expanding the application range of such *** this review,we introduce electrochromic zinc(Zn)-ion battery systems,which effectively overcome the limitation of low energy density,and provide illustrative examples of their applicability across diverse *** many recent research works are present for electrochromic Zn-ion batteries,little review has so far taken *** objective is to discuss on the current progress and future directions for electrochromic Zn-ion batteries,which are applicable for wearable electronics applications and energy storage *** review provides an initial milestone for future researchers in electrochromic energy storage and zinc-ion batteries,which will lead to a stream of future works related to them.

关键词： Electrochromic Zn-ion battery Flexible Transition metal oxide Conductive polymer

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Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： Rui-Rui Liu Li-Bo Mao Shu-Hong Yu Division of Nanomaterials and chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

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