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Probing the Catalytic Degradation of Unsaturated Polyolefin Materials via Fe-Based Lewis Acids-Initiated Carbonyl–Olefin Metathesis

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Angewandte Chemie - International Edition 2025年 e202503408页

作者： Chen, Liangyu Wang, Zhihao Fang, En Fan, Zhiqiang Song, Shaofei MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou310027 China

Degradation and recyclability of polymeric materials, including extensively used polyolefins, are becoming increasingly necessary. Chemically stable saturated polyolefin backbones make their degradation frustratingly challenging. The current effective strategy is to create cleavable defects, e.g., C═C double bonds along the backbone, and subsequently depolymerize them via cross-metathesis reaction with olefins. High-value chemicals or reusable polymeric segments are obtained. This two-step protocol provides operable means for alleviating plastics problems. There are several approaches to introduce unsaturation into a polymer backbone, like dehydrogenation or copolymerization of olefins and conjugated dienes. However, for the second step, to conduct a cross-metathesis reaction, only noble metal catalysts can be used most of the time. Regardless of their limited availability, the fact that these organometallics are unfavorably sensitive to impurities would raise barriers in industrial practices. Herein we employed earth-abundant and inexpensive iron-based Lewis acids to initiate carbonyl–olefin metathesis reactions between ketone/aldehyde reagents and unsaturated polyolefins. After explorations in poly(diene)s and industrial thermoplastic elastomers, we extended this protocol to degrade low-density polyethylene (LDPE). Low-molecular weight PE wax-like products were obtained as useful chemicals. This catalytic degradation system is expected to enable the development of more efficient metathesis strategies to promote degradation of polyolefins and pave sustainable ways for reuse of polymeric materials. © 2025 Wiley-VCH GmbH.

关键词： Low density polyethylenes

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Light-driven Self-sustained Rolling of Cylinder Hydrogels with Fast and Anisotropic Responses

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Chinese Journal of Polymer Science 2025年第4期43卷 548-555页

作者： Qing-Li Zhu Han-Lei Cheng Wei-Xuan Liu Yin-Bin Xiao Xin-Lei Wu Josef Breu Wei Hong Zhi-Jian Wang Qiang Zheng Zi-Liang Wu Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou310058China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen518055China Bavarian Polymer Institute and Department of Chemistry University of BayreuthUniversitätsstrasse 3095440BayreuthGermany Institute for Chemical Reaction Design and Discovery Hokkaido UniversitySapporo001-0021Japan

Achieving continuous motions typically requires dynamic external stimuli for cyclic deformation,or crafted geometries with intricate modules to form a self-regulated feedback loop upon static *** is still a grand challenge to realize self-sustained motion in soft robots subject to unchanging environment,without complex geometry or a control *** this work,we report soft robots based on an anisotropic cylindrical hydrogel showing self-regulated,continuous rolling motions under constant light *** robots are animated by mirror-symmetry-breaking induced by photothermal strain *** self-sustained motion is attributed to the fast and reversible deformation of the gel and the autonomous refresh of the irradiated region during the rolling *** hydrogel robots can reach a rolling speed of 1.27 mm·s^(-1)on a horizonal surface and even climb a ramp of 18°at a speed of 0.57 mm·s^(-1)in an aqueous ***,the hydrogel robots can overcome an obstacle,with rolling direction controllable through irradiation angle of the light and local irradiation on selective *** work suggests a facile strategy to develop hydrogel robots and may provide unforeseen inspirations for the design of self-regulated soft robots by using other intelligent materials.

关键词： Self-sustained motions Light-driven Rolling Anisotropic hydrogels Soft robots

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Engineering tiramisu-like phase change nanocomposite for superior thermal energy management and electromagnetic interference shielding

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材料科学技术（英文版） 2025年第3期206卷 113-124页

作者： Boyang Hu Hong Guo Ting Li Xiwei Cao Min Cao Weiyan Qi Ying Cui Baoan Li Carbon Neutrality Interdisciplinary Science Centre Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media PollutionCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China Carbon Neutrality Interdisciplinary Science Centre Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media PollutionCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China Department of Energy and Chemical Engineering Tianjin Ren'ai CollegeTianjin 301636China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Laboratoire des Solides Irradiés CEA/DRF/lRAMISEcole Poly techniqueCNRSInstitut Poly technique de ParisPalaiseau F-91128France

Exploiting advanced nanocomposites isochronally integrating outstanding thermal conductivity(TC)and electromagnetic interference shielding effectiveness(EMI SE)can boost the cutting-edge application of phase change ***,we report a tiramisu-like composite(GMP),where the typical"crust-and-cheese"hierarchical structure is replicated by an innovative two-step bidirectional freezing assem-bly(BFA)and compressive ***-aligned graphene array(G-GA)with ultralow ther-mal resistance is fabricated through 1st BFA and *** the 2nd BFA,the MXene-CNF crosslinking network with hydrogen-bond actions is used for encapsulating polyethylene glycol(PEG)onto the microlayers of the G-GA ***,the microlaminated GMP4 achieves a recorded TC of 34.05 W m-1 K-1,unprecedented EMI SE of 87.4 dB,and preferable enthalpy density of 179.4 J cm-3,along with leakage-free function,and eminent thermal ***,the GMP-loaded equipment is demonstrated for efficient microelectronics cooling and sustainable solar energy *** work opens new avenues for multiscale designing multifunctional macro-composites,broadening the application prospects in advanced electronics and solar energy utilization systems.

关键词： Phase change composite Multiscale structure construction Bidirectional freezing assembly Thermal management EMI shielding

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Grafting Hyperbranched Polylysine to Polysulfone Porous Membrane: A Promising Route for Modulating Membrane Multi-Properties

SSRN

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SSRN 2025年

作者： Cui, Ronglu Wang, Chuyao Zhu, Liheng Zhao, Zihao Zhao, Yu Xue, Yunyun Zhu, Ziran Zhu, Baoku Zhejiang University Hangzhou310058 China Center of Healthcare Materials Shaoxing Institute Zhejiang University Shaoxing312000 China MOE Key Laboratory of Macromolecular Synthesis and Functionalization China

Because of the hydrophobic characteristics of the surfaces of bio-ultrafiltration membranes, these membranes exhibit a propensity for the adhesion of contaminants and bacteria during the separation process, which severely impairing both the efficiency and longevity of the membranes. To address this pressing problem, this study introduces hyperbranched polylysine (HBPL) onto the surface of polysulfone ultrafiltration (PSF UF) membranes. This innovative approach significantly enhances the hydrophilicity of the membrane surface while endowing the membrane with robust antibacterial property. The results indicated that the modified UF membrane presented lower BSA adhesion (40.5% of the original PSF membrane), and higher flux recovery (79.6%) compared with the original PSF UF membrane. Additionally, the modified membranes were demonstrated to exhibit effective broad-spectrum antibacterial activity (95.2% against E. coil and 94.8% against S. aureus). Furthermore, the in vitro hemolytic activity assay and cytocompatibility test confirmed their non-toxicity and good biocompatibility. By controlling the surface grafting density of HBPL, a hydrophilic contact-killing surface with hydration repulsion was obtained, achieving synergistic antibacterial and anti-protein adhesion activity. The method of membrane fabrication employed in this study was found to be convenient and low-cost, suggesting its significant potential for application in practical settings. © 2025, The Authors. All rights reserved.

关键词： Grafting (chemical)

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Bioprosthetic heart valves with zwitterionic copolymer grafting to improve the properties of endothelialization and anti-calcification

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Biomedical Materials (Bristol) 2025年第3期20卷 2025 May 2页

作者： Zhu, Daoyang Luo, Yu Huang, Shenyu Ma, Lie MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310058 China Department of Ophthalmology The Second Affiliated Hospital Zhejiang University School of Medicine Zhejiang Hangzhou China

Heart valve replacement surgery has been the most effective treatment for severe valvular heart disease. Bioprosthetic heart valves (BHVs) crosslinked by glutaraldehyde (GA) have non-negligible advantages in clinical applications. However, structural valve degeneration, calcification, insufficient re-endothelialization and other factors lead to a shortened service life of BHVs. In this study, GA-crosslinked decellularized heart valves (GADHVs) were grafted with zwitterionic copolymer (PSBG) of [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide and glycidyl methacrylate, and further treated with Arg-Glu-Asp-Val (REDV) peptide to obtain REDV-PSBG-GADHVs with anti-fouling ability and endothelial cell affinity. REDV-PSBG-GADHVs exhibited good collagen stability, reliable mechanical property and excellent hemocompatibility. Moreover, in vitro and in vivo experiments demonstrated that REDV-PSBG-GADHVs exhibited better endothelialization property, lower immune responses and reduced calcification than GADHVs. This modified strategy for heart valve fabrication, which can improve the effect of anti-calcification and endothelialization while maintaining the original advantages of BHVs, shows great potential for application in heart valve replacement. © 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.

关键词： anti-calcification bioprosthetic heart valves endothelialization REDV zwitterionic polymer grafting

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FERROFERRIC OXIDE/CHITOSAN SCAFFOLDS WITH THREE-DIMENSIONAL ORIENTED STRUCTURE

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Chinese Journal of Polymer Science 2012年第3期30卷 436-442页

作者：胡巧玲 Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of EducationZhejiang University

A facile approach to construct ferroferric oxide/chitosan composite scaffolds with three-dimensional oriented structure has been explored in this research. Chitosan and ferroferric oxide are co-precipitated by using an in situ precipitation method, and then lyophilized to get the composite scaffolds. XRD indicated that Fe304 was generated during the gel formation process, and increasing the content of magnetic particles could destruct the crystal structure of chitosan. When the content of magnetic particles is lower than 10%, the layer-by-layer structure and wheel spoke structure are coexisting in the scaffolds. Increasing the content of magnetic particles, just layer-by-layer structure could be observed in the scaffolds. Ferroferric oxide particles were uniformly distributed in the matrix, the size of which was about 0.48 gm in diameter, 2 gm in length. Porosity of magnetic chitosan composite scaffolds is about 90%. When the ratio of ferroferric oxide to chitosan is 5/100, the compressive strength of the material is 0.4367 MPa, which is much higher than that of pure chitosan scaffolds, indicating that the layer-by-layer and wheel spokes complex structure is beneficial for the improvement of the mechanical properties of chitosan scaffolds. However, increasing the content of ferroferric oxide, the compressive strength of scaffolds decreased, because of the decreasing of chitosan crystallization and aggregation of magnetic particles as stress centralized body. Another reason is that the layer-by-layer and wheel spokes complex structure makes bigger contributions for the compressive strength than the layer-by-layer structure does. Three-dimensional ferroferric oxide/chitosan scaffolds could be used as hyperthermia generator system, improving the local circulation of blood, promoting the aggradation of calcium salt and stimulating bone tissue regeneration.

关键词： Chitosan Ferroferric oxide Scaffold Three-dimensional oriented structure.

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A real-time ATP biosensor based on gradient porous hollow fiber membrane bioreactor with di-enzyme loading

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Microchemical Journal 2025年 214卷

作者： Ma, Shuyan Hu, Mengjia Zheng, Kaijie Bai, Mingxia Sun, Tongtong Bao, Yuheng Xu, Zhikang Chen, Dajing Huang, Xiaojun Key Laboratory of Macromolecular Synthesis and Functionalization (MOE) Engineering Research Center for Membrane and Water Treatment (Ministry of Education) Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China College of Pharmacy Hangzhou Normal University Hangzhou 311121 China

This study presents a novel ATP biosensor based on gradient-pore hollow fiber membranes (GPF) bioreactor with di-enzyme immobilization, enabling real-time monitoring of extracellular ATP release. Carbon nanotubes (CNT) were strategically affixed outside the hollow fiber membrane through vacuum filtration, establishing a three-dimensional conductive network. Platinum nanoparticles (Pt) were electrochemically deposited to enhance catalytic capability. The resulting GPF-CNT/Pt-DE biosensor exhibited high selectivity, excellent long-term stability, and good biocompatibility for simultaneous detection of glucose and ATP. The biosensor maintained 98.06 % (glucose) and 89.83 % (ATP) current responses post 4-day, 4 °C storage. The response of excess common interferents only accounted for 6.92 % of the ATP response. Notably, the biosensor facilitated in-situ monitoring of ATP secretion by culturing living cells within the GPF lumen, providing dynamic insights into cellular responses. This electrochemical approach, characterized by low instrument cost, addresses limitations associated with other detection methods and holds promise for advancing real-time and in-situ monitoring in diverse biomedical applications. © 2025

关键词： ATP Enzymatic bioelectrode Hollow fiber membrane In situ detection

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Effects of Nanosilica on Crystallization and Thermal Ageing Behaviors of Polyethylene Terephthalate

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Chinese Journal of Polymer Science 2015年第5期33卷 697-708页

作者： Ying-jie Xu 宋义虎 Qiang Zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

The effects of nanosilica（SiO2） on crystallization and thermal aging behaviors of polyethylene terephthalate（PET） have been studied using differential scanning calorimetry（DSC） and polarized optical microscopy（POM）, viscometry, tensile testing and scanning electron microscopy（SEM）. For non-isothermal and isothermal crystallizations, the crystallization rate of PET increases considerably with increasing content of SiO2 providing a large number of nucleation sites, but the relative crystallinity of the nanocomposites has little differences with that of neat PET. According to POM observation, the nucleation of PET becomes faster and the nucleation density increases significantly with increasing SiO2 content. For PET and its nanocomposites thermally aged at 190 ℃, the results of intrinsic viscosity, carboxyl content and tensile test show that the degradation rate of PET is reduced with the addition of a small content of SiO2, but the degradation rate increases with further addition of SiO2, owing to the dual effect of SiO2 on PET degradation.

关键词： Polyethylene terephthalate Nanosilica Crystallization Thermal ageing

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RHEOLOGICAL PROPERTIES OF WHEAT GLIADINS IN AQUEOUS PROPANOL

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Chinese Journal of Polymer Science 2013年第5期31卷 809-814页

作者： Shao-min Sun 宋义虎 Qiang Zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

Rheological properties of wheat gliadins in 50% （V/F） aqueous propanol were carried out as a function of gliadin concentration c and temperature. The solutions at 20 g L-1 to 200 g L-1 behave as Newtonian fluids with an flow activation energy of 23.5-27.3 kJ mol-1. Intrinsic viscosity [η] and Huggins constant kH are determined according to Huggins plot at c 〈 120 g L-1. The results reveal that gliadins are not spherical shaped and the molecular size tends to increase with temperature due to improved solvation.

关键词： Gliadin Solution Rheological properties Intrinsic viscosity.

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PROBING THE ROLES OF DIETHYLALUMINUM CHLORIDE IN PROPYLENE POLYMERIZATION WITH MgCl_2-SUPPORTED ZIEGLER-NATTA CATALYSTS

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Chinese Journal of Polymer Science 2013年第4期31卷 583-590页

作者： Jie Hu Bin Han Xian-rong Shen Zhi-sheng Fu 范志强 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

In this article, the effect of diethylaluminum chloride （DEAC） in propylene polymerization with MgC12-supported Ziegler-Natta catalyst was studied. Addition of DEAC in the catalyst system caused evident change in catalytic activity and polymer chain structure. The activity decrease in raising DEAC/Ti molar ratio from 0 to 2 is a result of depressed production of isotactic polypropylene chains. The number of active centers in fractions of each polymer sample was determined by quenching the polymerization with 2-thiophenecarbonyl chloride and fractionating the polymer into isotactic, medium- isotactic and atactic fractions. The number of active centers in isotactic fraction （[Ci＊]/[Ti]） was lowered by increasing DEAC/Ti molar ratio to 2, but further increasing the DEAC/Ti molar ratio to 20 caused marked increase of [Ci＊]/[Ti]. The number of active centers that produce atactic and medium-isotactic PP chains was less influenced by DEAC in the range of DEAC/Ti = 0-10, but increased when the DEAC/Ti molar ratio was further raised to 20. The propagation rate constant of Ci＊（k^i） was evidently increased when DEAC/Ti molar ratio was raised from 0 to 5, but further increase in DEAC/Ti ratio caused gradual decrease in kpi. The complicated effect of DEAC on the polymerization kinetics, catalysis behaviors and polymer structure can be reasonably explained by adsorption of DEAC on the central metal of the active centers or on Mg atoms adjacent to the central metal

关键词： Supported Ziegler-Natta catalyst Diethylaluminum chloride Propylene polymerization Catalysis mechanism.

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