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Copolymerization of ethylene and isoprene via silicon bridge metallocene [rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2] catalyst: A new way to control the composition and microstructure of copolymers

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Chemosphere 2024年 347卷

作者： Ali, Amjad Naveed, Ahmad Maroń, Anna Younis, Muhammad Adnan Moradian, Jamile Mohammadi Yousaf, Balal Aziz, Tariq Ali, Rai Nauman Ahmad, Naushad Alomar, Suliman Yousef Zheqiang, Fan Guo, Li School of Materials Science & Engineering Jiangsu University Zhenjiang212013 China Institute of Chemistry University of Silesia Szkolna 9 Katowice40-600 Poland MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou310027 China Institute of Microscale Optoelectronics Shenzhen University Shenzhen518060 China Department of Technologies and Installations for West Management Faculty of Engineering Silesian University of Technology Konarskiego 18 Gliwice44-100 Poland School of Engineering Yunqi Campus Westlake University Zhejiang Hangzhou310024 China Laboratory of Inorganic Materials for Sustainable Energy Technologies Mohammed IV Polytechnic University Benguirer Morocco Department of Chemistry College of Science King Saud University Riyadh11451 Saudi Arabia Zoology Department College of Science King Saud University Riyadh11451 Saudi Arabia

The copolymerization of ethylene (E) with isoprene (Ip) was performed catalyzed by a symmetrical catalyst exhibiting a silicon bridge [rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2 with the combination of borate/TIBA activator. The effect of cocatalyst, Ip concentration, and polymerization temperature on the activity, molecular weight (Mw), distribution (MWD), comonomer composition, chain structure (regio- and stereoselectivity), and resulting side reactions were logically addressed. Gel-permeation chromatography (GPC) was used to characterize the Mw and polydispersity, while nuclear magnetic resonance (NMR) was employed for the chain structure of the polymers. The catalytic activity was significantly lower by increasing the Ip concentration in the feed, and the isoprene content in resulting polymers was lower under the reaction condition, leading to higher activity. Insertion of isoprene units in polymer structure demonstrates the higher regioselectivity for the 3,4 connections than the 1,4 connections and is expected to be a high-resistance polymer against acids. The MWD presented monomodal even with a higher concentration (1.44 mol/L) and did not appear as low Mw peaks of Ip. The Mw was higher with a broader MWD when purely TIBA was used as a cocatalyst, and it significantly reduced and presented a narrowed MWD with TEA in the cocatalyst. The higher efficiency of the catalyst for the higher insertion of Ip (C=C double bond) effectively modifies the polymer backbone. It is expected to be a promising candidate for easily degradable and favorable solutions for solving environmental problems caused by PE. wastes. © 2023 Elsevier Ltd

关键词： Ethylene

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Aqueous Developable and CO2-Sourced Chemical Amplification Photoresist with High Performance

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Angewandte Chemie 2024年第32期136卷

作者： Dr. Xin-Yu Lu Rui-Sheng Zhang Dr. Guan-Wen Yang Prof. Qiang Li Prof. Bo Li Prof. Guang-Peng Wu MOE Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310058 China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou 310027 China Key Laboratory of Organosilicon Chemistry and Material Technology Ministry of Education College of Material Chemistry and Chemical Engineering Hangzhou Normal University Hangzhou 311121 Zhejiang China

Seeking high-performance photoresists is an important item for semiconductor industry due to the continuous miniaturization and intelligentization of integrated circuits. Polymer resin containing carbonate group has many desirable properties, such as high transmittance, acid sensitivity and chemical formulation, thus serving as promising photoresist material. In this work, a series of aqueous developable CO 2 -sourced polycarbonates (CO 2 -PCs) were produced via alternating copolymerization of CO 2 and epoxides bearing acid-cleavable cyclic acetal groups in the presence of tetranuclear organoborane catalyst. The produced CO 2 -PCs were investigated as chemical amplification resists in deep ultraviolet (DUV) lithography. Under the catalysis of photogenerated acid, the acetal (ketal) groups in CO 2 -PC were hydrolysed into two equivalents of hydroxyl groups, which change the exposed area from hydrophobicity to hydrophilicity, thus enabling the exposed area to be developed with water. Through normalized remaining thickness analysis, the optimal CO 2 -derived resist achieved a remarkable sensitivity of 1.9 mJ/cm 2 , a contrast of 7.9, a favorable resolution (750 nm, half pitch), and a good etch resistance (38 % higher than poly( tert- butyl acrylate)). Such performances outperform commercial KrF and ArF chemical amplification resists (i.e., polyhydroxystyrene-derived and polymethacrylate-based resists), which endows broad application prospects in the field of DUV (KrF and ArF) and extreme ultraviolet (EUV) lithography for nanomanufacturing.

关键词： carbon dioxide polycarbonate chemical amplification resist water developable organocatalysis

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Corrigendum to "Enzyme-responsive multifunctional peptide coating of gold nanorods improves tumor targeting and photothermal therapy efficacy" [Acta Biomaterialia 2019, 86, 363-372]

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Acta biomaterialia 2024年 186卷 520页

作者： Liming Wu Bingyi Lin Huang Yang Jing Chen Zhengwei Mao Weilin Wang Changyou Gao Division of Hepatobiliary and Pancreatic Surgery Department of Surgery The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 China Key Laboratory of Precision Diagnosis and Treatment for Hepatobiliary and Pancreatic Tumor of Zhejiang Province The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 China. Division of Hepatobiliary and Pancreatic Surgery Department of Surgery The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 China. MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China. MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China. Electronic address: zwmao@***.

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Four-Membered Ring-Embedded Cycloarene Enabling Anti-Aromaticity and Ultra-Narrowband Emission

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Angewandte Chemie 2024年第43期136卷

作者： Rong Zhang Zuping Xiong Dongyue An Jiangyu Zhu Yuanhe Gu Prof. Dr. Haoke Zhang Prof. Dr. Gang Zhou Prof. Dr. Yunqi Liu Prof. Dr. Xuefeng Lu Department of Materials Science State Key Laboratory of Molecular Engineering of Polymers Fudan University Shanghai 200433 China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310058 China Lab of Advanced Materials State Key Laboratory of Molecular Engineering of Polymers Fudan University Shanghai 200433 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The synthesis of fully fused π-conjugated cycloarenes embedded with nonbenzenoid aromatics is challenging. In this work, the first example of four-membered ring-embedded cycloarene ( MF2 ) was designed and synthesized in single-crystal form by macrocyclization and ring fusion strategies. For comparison, single bond-linked chiral macrocycle MS2 without two fused four-membered rings and its linear-shaped polycyclic benzenoid monomer L1 were also synthesized. The pronounced anti-aromaticity of four-membered rings significantly adjusts the electronic structures and photophysical properties of cycloarene, resulting in an enhancement of the photoluminescence quantum yield (PLQY) from 10.66 % and 10.74 % for L1 and MS2 , respectively, to 54.05 % for MF2 , which is the highest PLQY among the reported cycloarenes. Notably, owing to the embedded anti-aromatic four-membered rings that reduce structural displacements, MF2 exhibits an ultra-narrowband emission with a single-digit full-width at half-maximum (FWHM) of only 7 nm (0.038 eV), which sets a new record among all reported organic narrowband luminescent molecules, and represents the first example of ultra-narrowband emission in conventional polycyclic aromatic hydrocarbons (PAHs) devoid of heteroatoms.

关键词： cycloarenes four-membered ring anti-aromaticity ultra-narrowband emission full-width at half-maximum (FWHM)

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Assessing the synergy effect of additive and matrix on single-crystal growth: Morphological revolution resulted from gel-mediated enhancement on CIT-calcite interaction

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Chinese Chemical Letters 2018年第8期29卷 1296-1300页

作者： Yujing Liu Ying Tan Jie Ren Hongzheng Chen Hanying Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering State Key Laboratory of Silicon Materials Zhejiang University

It is well known that in biomineralization, the inorganic solids crystallized in the presence of organic phases, which are generally recognized as additives and matrix, leading to the crystal morphology modification. However, the synergy effects of both soluble additive and insoluble matrix on regulating the morphology of synthetic single-crystals are less studied. Here, we examine the morphological revolution of calcite single crystals induced by the additive, citrate（CIT）, or/and the matrix, agarose gel network. The agarose gel matrix is inert to the crystal morphology in the sense that the agarose gelgrown calcite crystals maintain in characteristic rhombohedra. In contrast, CIT additives are active in crystal morphology modification and crystals begin to exhibit curved rough surfaces when grown in solution with the concentration of CIT coated Au nanoparticles（[CIT-Au NPs]） of more than 2.25 mg/***, once agarose gel and CIT-Au NPs are simultaneously introduced, the curved morphological feature emerges at a much lower [CIT-Au NPs] of around 0.2 mg/mL. Increasing the gel concentrations further reduce the [CIT-Au NPs] needed to trigger calcite morphological modification, suggesting that the gel networks reduce the CIT diffusion and thereby enhance the kinetic effects of CIT on crystallization. As such, this work may have implications for understanding the mechanism of hierarchical biominerals construction and provide rational strategy to control single-crystal morphologies.

关键词： Biomineralization Synergy effect Additive CIT Gel matrix Calcite single-crystal Morphology

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A non-fullerene acceptor enables efficient P3HT-based organic solar cells with small voltage loss and thickness insensitivity

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Chinese Chemical Letters 2019年第6期30卷 1277-1281页

作者： Ning Wang Weitao Yang Shuixing Li Minmin Shi Tsz-Ki Lau Xinhui Lu Rafi Shikler Chang-Zhi Li Hongzheng Chen MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon Materials Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Department of Physics The Chinese University of Hong Kong Hong Kong 999077 China Department of Electrical and Computer Engineering Ben-Gurion University of the Negev Beer-Sheva 8410501 Israel

Poly(3-hexylthiophene)(P3HT) is a low-cost polymer donor for organic solar cells (OSCs). However, the P3HT-based OSCs usually give low power conversion efficiencies (PCEs) due to the wide bandgap and the high-lying energy levels of P3HT. To solve this problem, in this work, we design and synthesize a new A-D-A type non-fullerene acceptor, DFPCBR, which owns an electron-donating (D) core constructed by linking a 2,5-difluorobenzene ring with two cyclopentadithiophene moieties, and two electron-accepting (A) end-groups of benzo[c][1,2,5]thiadiazole connected with 3-ethyl-2-thioxothiazolidin-4-one. Because of the strong electron-donating ability and large conjugation effect of D core, DFPCBR shows appropriate energy levels and a narrow bandgap matching well with those of P3HT. Therefore, with P3HT as the donor and DFPCBR as the acceptor, the OSCs possess broad absorption range from 350 nm to 780 nm and the reduced energy loss (Eloss) of 0.79 eV (compared with ~1.40 eV for the P3HT:PC61BM device), providing a good PCE of 5.34% with a high open-circuit voltage (VOC) of 0.80 V. Besides, we observe that the photovoltaic performances of these devices are insensitive to the thickness of the active layers:even if the active layer is as thick as 320 nm,~80%of the best PCE is maintained, which is rarely reported for fullerene-free P3HT-based OSCs, suggesting that DFPCBR has the potential application in commercial OSCs in the future.

关键词： Poly(3-hexylthiophene) Non-fullerene acceptors Organic solar cells Energy loss Thickness insensitivity

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synthesis and self-assembly of poly(ethylene glycol)-block-poly(N-3-(methylthio)propyl glycine)and their oxidation-sensitive polymersomes

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Chinese Chemical Letters 2020年第7期31卷 1931-1935页

作者： Yangwei Deng Hui Chen Xinfeng Tao Sylvain Trepout Jun Ling Min-Hui Li Chimie ParisTech PSL University ParisCNRSInstitut de Recherche de Chimie ParisParis 75005France MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Institut Curie Inserm US43University Paris SaclayOrsay Cedex 91405France Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Amphiphilic block copolymers poly(ethylene glycol)-block-poly(N-3-(methylthio)propyl glycine)(PEGb-PMeSPG)were synthesized via ring-opening polymerization of N-3-(methylthio)propyl glycine Nthiocarboxyanhydride(MeSPG-NTA)initiated by amino-terminated *** self-assemblies of three PEG-b-PMeSPG copolymers with different PMeSPG block lengths were first prepared by nanoprecipitation method using THF and DMF,respectively,as the organic solvent,and their morphologies were studied by Cryo-EM and *** prepare polymersomes loaded with glucose oxidase(GOx),double emulsion method followed by extrusion treatment was *** oxidation-responsive disruption of polymersomes was achieved upon the introduction of glucose because of the oxidants generated insitu by GOx/glucose.

关键词： Polypeptoid Self-assembly Polymersome Oxidation-responsive Glucose oxidase

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A Binary Silicon-Centered Organoboron Catalyst with Superior Performance to That of Its Bifunctional Analogue

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Angewandte Chemie 2023年第48期135卷

作者： Cheng-Kai Xu Guan-Wen Yang Chenjie Lu Prof. Dr. Guang-Peng Wu MOE Key Laboratory of Macromolecular Synthesis and Functionalization Key Laboratory of Adsorption and Separation Materials and Technologies of Zhejiang Province Department of Polymer Science and Engineering Zhejiang University Yuhangtang Road 866 Hangzhou 310058 China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material Technology Ministry of Education Hangzhou Normal University Hangzhou 311121 China

This work reported that a silicon-centered alkyl borane/ammonium salt binary (two-component) catalyst exhibits much higher activity than its bifunctional analogue (one-component) for the ring-opening polymerization of propylene oxide, showing 7.3 times the activity of its bifunctional analogue at a low catalyst loading of 0.01 mol %, and even 15.3 times the activity at an extremely low loading of 0.002 mol %. By using 19 F NMR spectroscopy, control experiments, and theoretical calculation we discovered that the central silicon atom displays appropriate electron density and a larger intramolecular cavity, which is useful to co-activate the monomer and to deliver propagating chains, thus leading to a better intramolecular synergic effect than its bifunctional analogue. A unique two-pathway initiation mode was proposed to explain the unusual high activity of the binary catalytic system. This study breaks the traditional impression of the binary Lewis acid/nucleophilic catalyst with poor activity because of the increase in entropy.

关键词： Boron Catalysts Ethers Polymerization Silicon

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Virtually Wall-Less Tubular Sponges as Compartmentalized Reaction Containers

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Research 2019年第1期2019卷 868-877页

作者： Shaohua Jiang Viktoria Gruen Sabine Rosenfeldt Anna S.Schenk Seema Agarwal Zhi-Kang Xu Andreas Greiner College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China Universitat Bayreuth Physical ChemistryUniversitatsstrasse 3095447 BayreuthGermany Universitat Bayreuth Macromolecular ChemistryBavarian Polymer InstituteUniversitatsstrasse 3095440 BayreuthGermany MOE Key Laboratory of Macromolecular Synthesis and Functionalization Key Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceDepartment of Polymer Science and EngineeringZhejiang University310027 HangzhouChina

Sponges are open cellular materials with numerous interesting ***,the potential of compartmentalized sponges has not been explored although many new properties and applications could be *** found that compartmentalized fbrous ultraporous polymer sponges with superhydrophobic surfaces could be designed as virtually wall-less reaction *** this,for example,the efcient removal of CO_(2) from water and the controlled mineralization of calcium carbonate are *** high porosity(>99%)and superhydrophobicity make these sponges ideal candidates to hold alkanolamine solution for absorbing CO_(2) and exchange gas through the walls of the *** tubular sponge exhibits a much higher evaporation rate than a glass tube with the same diameter due to the much larger contact area between water and ***,the spongy reaction container also possesses a much faster adsorption rate,smaller equilibration time and higher efciency for CO_(2) adsorption than the glass tube *** addition,these tubular sponges are also utilized to precipitate calcium carbonate by ammonium carbonate decomposition,which can control the deposition rates and products by tailoring the porosity and surface chemistry in the *** new sponges provide an ideal basis for numerous new applications,for example,as breathable pipe lines for gas-liquid exchange,slag slurry carbonization,humidifer,and blood enricher.

关键词： sponge porosity adsorption

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Vertically Oriented Microporous Membranes Prepared by Bidirectional Freezing

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Chinese Journal of Polymer Science 2018年第7期36卷 880-887页

作者： Sen-He Chen Bai-Heng Wu Jin-Cheng Fu Guo-Jun Wang Ling-Shu Wan Zhi-Kang Xu Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Key Laboratory of Adsorption and Separation Materials &Technologies of Zhejiang Province Zhejiang University

Polystyrene membranes with precisely controlled and vertically oriented pores are fabricated by a bidirectional freezing process. In this process, the influence of polymer in growth of diphenyl sulfone （DPS） crystals has been demonstrated by XRD and simulated by DFT based on the interaction between DPS crystal faces and polystyrene （PS）. The influence of temperature gradient on membrane structures is also elucidated. Compared to the original membrane and modified traditional membranes, modified PS membranes with vertically oriented pores show large and stable fluxes in the processes of multiple oil and water separation.

关键词： Separation membrane Vertical pores Bidirectional freezing Oil separation

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