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Science China Chemistry 2025年第1期 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing Zhou Bin Wang Yuesheng Li tianjin key laboratory of composite & functional materials School of Materials Science and Engineering Tianjin University

Living/controlled cationic ring-opening polymerization （ROP） of L-lactide is a promising approach to isotactic-rich and crystalline poly（L-lactide）.In contrast with the unsubstituted lactones,L-LA can not be polymerized by organic Lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of L-LA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of L-LA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid L-LA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PLLA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of L-LA catalyzed by an organic ion pair.

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Synthesis of Bimodal Distributed Cyclic Olefin Copolymers with Improved Tensile Properties

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Chinese Journal of Chemistry 2022年第16期40卷 1931-1938页

作者： Feng Wang Dong Huang Huan Gao Fei Wang Li Pan Yuesheng Li tianjin key Lab of composite&functional materials School of Materials Science and EngineeringTianjin UniversityTianjin300072 China

Ethylene/norbornene(NBE)copolymers are the most representative and widely-used cyclic olefin copolymers(COCs).Higher NBE content in COCs leads to higher transparency,glass transition temperature and mechanical strength,but also makes the COC more brittle and therefore hampers its end *** this study,to improve the brittleness of COCs while maintaining their high strength,heat-resistant and transparency,bimodal distributed COCs have been prepared via two selective catalysts reactive blending in one *** shape of the molecular weight distribution curves of the obtained COCs could be easily controlled by adjusting the proportion of the two *** COCs maintained high glass transition temperature,balanced tensile performance,high transparency.

关键词： Cyclic olefin copolymer Bimodal distributed polymer Amorphous materials Organocatalysis Mechanical properties

In situ construction of Cu(Ⅰ)-Cu(Ⅱ) pairs for efficient electrocatalytic nitrate reduction reaction to ammonia

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Journal of Energy Chemistry 2025年第1期 106-113页

作者： Muyun Zheng Yuchi Wan Leping Yang Shen Ao Wangyang Fu Zhengjun Zhang Zheng-Hong Huang Tao Ling Feiyu Kang Ruitao Lv State key laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Institute of New Energy materials and Engineering School of Materials Science and Engineering Fuzhou University key laboratory of Advanced materials (MOE) School of Materials Science and Engineering Tsinghua University key laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and Engineering Tianjin University

Electrocatalytic nitrate reduction reaction （NO3-RR） to ammonia under ambient conditions is expected to be a green process for ammonia synthesis and alleviate water pollution *** report a CuO nanoparticles incorporated on nitrogen-doped porous carbon （CuO@NC） catalyst for *** of Cu（Ⅱ） is reduced to Cu（Ⅰ） during the NO3-RR process to construct Cu（Ⅰ）-Cu（Ⅱ） pairs,confirmed by in situ X-ray photoelectron spectroscopy （XPS） and Raman *** functional theory （DFT） calculations indicated that the formation of Cu（Ⅰ） could provide a reaction path with smaller energy barrier for NO3-RR,while Cu（Ⅱ） effectively suppressed the competition of hydrogen evolution reaction （HER）.As a result,CuO@NC catalyst achieved a Faradaic efficiency of 84.2% at -0.49 V versus reversible hydrogen electrode （RHE）,and a NH3yield rate of 17.2 mg *** -0.79 V ***,higher than the HaberBosch process (<3.4 g h-1g-1cat.).This work may open a new avenue for effective NO3-RR by modulating oxidation states.

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A conductive and biodegradable hydrogel for minimally delivering adipose-derived stem cells

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Science China(Technological Sciences) 2019年第10期62卷 1747-1754页

作者： SHANG YingYing LIANG Wei TAN BaoYu XIAO Meng ZOU Yang LIU WenGuang WANG Wei tianjin key laboratory of composite and functional materials School of Materials Science and Engineering Tianjin University

Injectable hydrogel is one of the most important biomaterials for tissue engineering and drug delivery. However, it is still a challenge to obtain an injectable hydrogel with conductive property on account of the poor water solubility of conductive polymers. Here, a conductive hydrogel with controllable biodegradability was constructed for minimally delivering adipose mesenchymal stem cells(ADSCs). Firstly, a disulfide containing and hyperbranched polymer structure poly(β-amino ester)(PBAE) with multi-acrylate end groups was synthesized by poly(ethylene glycol) diacrylate(PEGDA) and cystamine, and then tetraaniline(TA) was grafted on the PBAE chain to obtain a conductive PBAE-TA polymer. PBAE-TA shows a good water solubility, which can be crosslinked by thiol-modified hyaluronic acid(HA-SH) due to the click reaction between acrylate and thiol to in situ form a hydrogel within 1 min. The hydrogel illustrates a good electrical conductivity of 9.6×10–3 S/cm and a controllable biodegradable behavior in dithiothreotol(DTT) solution. PBAE-TA/HA-SH hydrogel was subcutaneously injected for delivering ADSCs. The gene expression of Cx43 and TGF-β1 were up-regulated by PBAE-TA/HA-SH hydrogel, suggesting an enhancement in the electrical coupling and an anti-inflammatory property. This injectable, biodegradable, and conductive hydrogel can effectively deliver stem cells, which might be used in skin, muscle, and myocardium regeneration.

关键词： injectable hydrogel conductivity biodegradability ADSCs

PLASMA MODIFICATION OF POLYPROPYLENE SURFACES AND GRAFTING COPOLYMERIZATION OF STYRENE ONTO POLYPROPYLENE

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Chinese Journal of Polymer Science 2012年第3期30卷 423-435页

作者：马桂秋 School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The surface of polypropylene （iPP） is modified with glow discharge plasma of Ar, so that the modified surfaces of iPP films are obtained. The studies of scanning electron microscopy （SEM） show the surface etching pattern of iPP films. The chemical structures of iPP films are confirmed by X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared （FTIR） spectroscopy. The wetting properties of modified surfaces of iPP films are characterized by contact angle, and the free energy of surfaces is calculated. The free radical of modification surfaces of iPP is measured by chemical method. The surfaces of iPP are achieved with Ar plasma treatment followed by grafting copolymerization with styrene （St） in St. The grafting polymer of St onto iPP is characterized by FTIR. The grafting rate is dependent on plasma exposure time and discharge voltage. The studies show that homopolymerization of St is undergone at the sane time during the graftingcopolymerization of St onto/PP.

关键词： Plasma treatment of polymer surface Plasma modification of polypropylene Grafting copolymerization of polypropylene surface.

A high strength, anti-fouling, self-healable, and thermoplastic supramolecular polymer hydrogel with low fibrotic response

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Science China(Technological Sciences) 2019年第4期62卷 569-577页

作者： WANG HongBo LI HaoFei WU YuanHao YANG JianHai LIU WenGuang School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The fibrotic response plays an important role in the performance and longevity of implantable devices. Thus, development of effective anti-inflammatory and anti-fibrosis biomaterial implants has become an urgent task. In this work, we developed a novel supramolecular polymer hydrogel through the copolymerization of N-acryloyl glycinamide(NAGA) and carboxybetaine acrylamide(CBAA) in the absence of any chemical crosslinker, which the mechanical properties being tunable through changing the monomer concentration and the monomer ratio over a broad scope. The hydrogel possessed the superior mechanical performances: high tensile strength(～1.13 MPa), large stretchability(～1200%), and excellent compressive strength(～9 MPa) at high monomer concentration and NAGA/CBAA ratio. Introduction of CBAA could promote the self-healability, thermoplasticity of suparmolecular polymer hydrogels at lower temperatures, meanwhile dramatically improving anti-fouling *** analysis and in vitro cytotoxicity assays testified the excellent biocompatibility of the hydrogel. This high strength supramolecular polymer hydrogel with integrated multiple functions holds promising potentials as a scaffold biomaterial for treating degenerated soft supporting tissues.

关键词： supramolecular polymer hydrogel self-healing anti-protein absorption fibrotic response

Shear-induced Crystallization in Phase-separated Blends of Isotactic Polypropylene with Ethylene-Propylene-Diene Terpolymer

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Chinese Journal of Polymer Science 2015年第11期33卷 1538-1549页

作者：马桂秋 Da Li Jing Sheng School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The compatibility between isotactic polypropylene（iPP） and ethylene-propylene-diene terpolymer（EPDM） in the blends was studied. SAXS analysis indicates that iPP and EPDM phases in the binary blend are incompatible. Isothermal crystallization behaviors of iPP in phase-separated iPP/EPDM were studied by in situ POM equipped with a Linkam shear hot stage. It was found that typical spherulites of iPP were formed both in neat iPP and in iPP/EPDM blends. The radial growth rate（d R/dt） of spherulites of iPP in the blend was not influenced by EPDM phases. Further investigations on isothermal crystallization of iPP in iPP/EPDM after shear with a fixed shear time showed that the crystallization rate of iPP in the blends increased with increasing shear rates, whereas, the crystallization rate was much lower than that of neat iPP. WAXD results showed that β-crystal iPP was formed in neat iPP as well as in iPP/EPDM blends after shearing and the percentage of β-crystal bore a relationship to the applied shear rate. The presence of EPDM resulted in lower percentage of β-crystal in the blends than that in neat iPP under the same constant shear conditions. SAXS experiments revealed that shear flow could induce formation of oriented lamellae in iPP and iPP in the blends, and the presence of EPDM led to a reduced fraction of oriented lamellae.

关键词： Shear-induced crystallization Polypropylene EPDM Blends β-Crystal

Preparation of hydroxyapatite layer on Ti-based bulk metallic glasses by acid and alkali pre-treatment

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Rare Metals 2015年第1期34卷 22-27页

作者： Hao Hu Zhen-Duo Cui Sheng-Li Zhu Zhao-Yang Li Yan-Qin Liang Xian-Jin Yang School of materials Science and Engineering Tianjin University tianjin key laboratory of composite and functional materials

In this paper, a thin calcium phosphate layer was prepared on the surface of Ti4oZr10Cu36Pd14 bulk metallic glasses （BMGs）. All samples were dipped in HNO3 aqueous solution and boiled in 1.2 mol-L-I NaOH aqueous solution. After the two preliminary treatment steps, they were soaked in simulated body fluid （SBF） to form an apatite layer on the surface. After immersion for 12 days, a coating composed mainly of Ca-P particles was rapidly deposited on the surface of Ti40Zr10Cu36Pd14 bulk metallic glasses. The surfaces of chemically treated sam- ples and the samples after immersion in SBF were char- acterized by X-ray diffraction （XRD）, X-ray photoemission spectroscopy （XPS）, field emission scanning electron microscopy （FESEM）, and energy dispersive spectroscopy （EDS）. Analysis results indicate that this apatite coating consists of Ca-P particles with different diameters. In addition, the Ca/P ratio of the apatite coatings immersed for 14 days is 1.62, which is close to that of hydroxyapatite （HA）.

关键词： Metallic glass Titanium alloy Hydroxyapatite Thin film

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi Kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai key laboratory of Molecular Catalysis and Innovative materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential composite anode Sodium-ion batteries

Surface Modification of Polypropylene by Ethylene Plasma and Its Induced β-Form in Polypropylene

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Chinese Journal of Polymer Science 2015年第5期33卷 669-669,670-673页

作者：马桂秋 Ya-peng Liu Shu-xian Wei Jing Sheng School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

This study aims to investigate the chemical structure and morphology of plasmapolymers produced by deposition of ethylene on the surface of polypropylene. The deposition films（sediments） of ethylene plasma on the surface of polypropylene are nonuniform, and the characterization results indicate the existence of hydroxyl groups and aldehyde（or ketone） groups in the sediments. The sediment of ethylene plasma on the polypropylene surface could induce the growth of β-form crystals in the surface layer of polypropylene.

关键词： Plasma polymerization Plasma modification of polypropylene β-Form polypropylene