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Synthesis and Properties of Non-isocyanate Crystallizable Aliphatic Thermoplastic Polyurethanes

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Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1275-1280页

作者： LI Suqing DENG Yong ZHAO Jingbo ZHANG Zhiyuan ZHANG Jnuying YANG Wantai key laboratory of carbon fiber and functional polymers（Bering University of Chemical Technology） Ministry of Educatio State key laboratory of Chemical Resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

A simple non-isocyanate route synthesizing thermoplastic polyurethanes（TPUs） with good thermal and mechanical properties is described. Melt transurethane polycondensation of dimethyl 1,6-hexamethylene dicarbamate with 1,4-butanediol and 1,6-hexanediol was conducted at different molar ratios under the catalysis of tetrabutyl titanate. A series of crystallizable non-isocyanate TPUs with high molecular weight were prepared. The TPUs were characterized by gel permeation chromatography, FT-IR, 1 H-NMR, differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, AFM, and tensile tests. The TPUs exhibited Mn ranging from 12 500 to 26 400 g/mol, Mw from 16 700 to 56 400 g/mol, Tm up to 151.4 °C, and initial decomposition temperature over 241.8 °C. Their tensile strength reached 42.99 MPa with a strain at break of 30.00%. TPUs constructed simply with butylene, hexylene, and urethane linkages were successfully synthesized through a non-isocyanate route.

关键词： thermoplastic polyurethanes non-isocyanate route transurethane polycondensation properties dimethyl 1 6-hexamethylene dicarbamate

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia key laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State key laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National key laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

Simultaneously improved actuated performance and mechanical strength of silicone elastomer by reduced graphene oxide encapsulated silicon dioxide

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International Journal of Smart and Nano Materials 2015年第4期6卷 251-267页

作者： Nanying Ning Minglu Wang Jing Zhang Liqun Zhang Ming Tian State key Lab of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China laboratory of carbon fiber and functional polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029China

Herein,graphene oxide(GO)-encapsulated silica(SiO 2)hybrids(GO@SiO 2)were prepared via electrostatic self-assembly of the 3-aminopropyltriethoxysilane(APS)-modified SiO_(2) and *** as-prepared GO@SiO 2 was introduced into polydimethyl-siloxane(PDMS)elastomer to simultaneously increase the dielectric constant(k)and mechanical properties of ***,the in situ thermal reduction of GO@SiO_(2)/PDMS composites was conducted at 180℃ for 2 h to increase the interfacial polariz-ability of GO@SiO_(2).As a result,the values of k at 1000 Hz are largely improved from 3.2 for PDMS to 13.3 for the reduced GO@SiO_(2)(RGO@SiO_(2))/PDMS ***,the dielectric loss of the composites remains low(<0.2 at 1000 Hz).More importantly,the actuated strain at low electric field(5 kV/mm)obviously increases from 0.3%for pure PDMS to 2.59%for the composites with 60 phr of RGO@SiO_(2),an eightfold increase in the actuated *** addition,both the tensile strength and elastic modulus are obviously improved by adding 60 phr of RGO@SiO_(2),indicating a good reinforcing effect of RGO@SiO_(2) on *** goal is to develop a simple and effective way to improve the actuated performance and mechanical strength of the PDMS dielectric elastomer for its wider application.

关键词： graphene oxide(GO)-encapsulated silica(SiO_(2))hybrids electrostatic self-assembly polydimethylsiloxane(PDMS)elastomer dielectric constant(k)and mechanical properties actuated strain at low electric field

AQUEOUS SEC ANALYSIS OF CATIONIC polymers AS GENE CARRIERS

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Chinese Journal of Polymer Science 2011年第4期29卷 421-426页

作者：蒋序林 key laboratory of Biomedical polymers of ministry of education and Department of Chemistry Wuhan University

Cationic polymers have been receiving much attention as non-viral gene vectors. The aqueous mobile phase was optimized in combination with Shodex OHpak SB columns for size-exclusion chromatography （SEC） analysis of disulfide-containing poly（ethylene imine）（PEI） derivatives used in gene delivery. Addition of acetonitrile in mobile phase was shown to be able to suppress the hydrophobic interactions between polymer analytes and the stationary phase. The absolute molecular weights and distributions of the cationic polymers were determined directly from online SEC-MALS （multi-angle light scattering）/RI （refractive index detector）. The results demonstrate that a good SEC separation of disulfide-containing PEI derivatives used in gene delivery with little band broadening was achieved.

关键词： PEI derivatives Gene delivery Aqueous SEC Molecular weight Online MALS detector.

Local T regulatory cells depletion by an integrated nanodrug system for efficient chem-immunotherapy of tumor

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Science China Chemistry 2019年第9期62卷 1230-1244页

作者： Fan Gao Qian Cheng Miao-Deng Liu Lei Rong Chuan-Jun Liu Xian-Zheng Zhang key laboratory of Biomedical polymers of ministry of education Department of ChemistryWuhan University

T regulatory(Treg) cell is a major immunosuppressive factor that restrains the antitumor effect of immunotherapy, because it gets more after the immune activation and is hardly to be eliminated. Here, an acid-sensitive integrated nanodrug system is designed to activate antitumor immune response as well as locally deplete Treg cells with low side effect. The nanosystem is synthetized by coordinating doxorubicin(DOX) and pentoxifylline(PTX) with Zn ions, then stabilized via liposome encapsulation(denoted as DTX@Lipo). DTX@Lipo can activate antitumor immune effect by chemotherapy of DOX. Besides, the release of PTX inhibits c-Rel expression, leading to the reduction of Treg cells in tumor site. Owing to the good tumor accumulation and local drug release ability, DTX@Lipo exhibits better biosafety and convenience than traditional antibody blockade method for Treg cells depletion. According to the results of in vivo experiments, the nanodrug system can significantly increase the ratio between effector T(Teff) cells and Treg cells locally, resulting in an immunoactivated tumor microenvironment. Importantly, it exhibits significant antitumor effect when combined with PD-1 blockade therapy, providing great potential for tumor therapy.

关键词： tumor T regulatory cell nanodrug system PD-1 immune response

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： Li-Xu You Lan Tian Chun-Ling Guo Shun-Xi Li Yu-Cheng Liu Yu-Long Li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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Origin of Modulus Improvement for Epoxide-terminated Hyperbranched Poly(ether sulphone)/DGEBA/TETA Systems

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Chinese Journal of Polymer Science 2018年第8期36卷 991-998页

作者： Xue-Pei Miao Dao-Jian Cheng Ya-Dong Dai Yan Meng Xiao-Yu Li key laboratory of carbon fiber and functional polymers Ministry of Education College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State key laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China Neo Trident Technology Ltd (Beijing) Beijing 100190 China

It has been experimentally shown that epoxide-terminated hyperbranched polyether sulphone （EHBPES） can significantly improve the mechanical properties of traditional diglycidyl ether of bisphenol A/triethylenetetramine （DGEBA/TETA） systems, but the origin of the improvement is still unclear. In this work, we used molecular dynamics （MD） simulations to gain a thorough understanding of the origin of modulus improvement for EHBPES/DGEBA/TETA systems. It is found that the modulus of EHBPES/DGEBA/TETA systems increases with the increase of EHBPES loading. In addition, the crosslinking density, cohesive energy density （CED）, and free volume can be used to understand the modulus for EHBPES/DGEBA/TETA systems. It is shown that the highest modulus is achieved at 7 wt% EHBPES loading due to the highest crosslinking density and CED. When EHBPES loading is below 7 wt%, the higher CED and crosslinking density are responsible for the higher modulus. At higher loadings （〉 7 wt%）, the decreased modulus is closely related to the decreased crosslinking density and increased fractional free volume. It is expected that our results could be of great implications for designing high-performance epoxy materials.

关键词： Modulus Molecular simulation Epoxy resin

调控串联三金属AuAgCu异质结上*CO中间体的吸附构型,促进CO2通过不对称C-C耦合电还原为乙醇（英文）

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Science China Materials 2025年第1期 173-179页

作者：石永霞李俊俊闵志雯王鑫亿侯曼马昊庄泽超秦毓辰孙源淼王定胜张志成 key laboratory of Organic Integrated Circuit Ministry of Education & Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of Chemistry School of Science Tianjin University Faculty of Materials Science and Energy Engineering/Institute of Technology for carbon Neutrality Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Department of Chemistry Tsinghua University College of Sciences Henan Agricultural University

在电化学CO2还原反应中,合理调节关键中间体*CO的吸附构型可以促进碳-碳（C–C）偶联生成多碳产物.在这项工作中,理论计算表明,通过顶式吸附的*CHO和三重位吸附的*CO在Cu位点上进行C–C耦合是一种能量有利的途径.作为概念验证,制备了串...

在电化学CO2还原反应中,合理调节关键中间体*CO的吸附构型可以促进碳-碳（C–C）偶联生成多碳产物.在这项工作中,理论计算表明,通过顶式吸附的*CHO和三重位吸附的*CO在Cu位点上进行C–C耦合是一种能量有利的途径.作为概念验证,制备了串联三金属AuAgCu异质结（Au@Ag/Cu）,其中Au@Ag位点上顶式吸附的*CO溢流到Cu位点后转变为三重位吸附,然后该三重位吸附的*CO和Cu位点上顶式吸附的*CHO进行不对称C–C偶联,促进了乙醇产物的形成.在-0.3 V ***的低电位下,乙醇法拉第效率最高为65.9%.我们的工作通过调节中间产物的吸附构型,为串联催化的内在机制提供了新的见解.

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Silicone Elastomer with High Elongation at Break Used in Digital Light Processing 3D Printing

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Chinese Journal of Polymer Science 2023年第11期41卷 1786-1795,I0010页

作者： Tian-Xin Yu Ya-Yuan Liu Fu-Yue Tian Nan-Ying Ning Bing Yu Ming Tian State key laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China key laboratory of carbon fiber and functional polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029China

3D printing silicone elastomer has demonstrated great potential in diverse areas such as medical devices,flexible electronics and soft *** is of great value to investigate how to improve the mechanical properties,including tensile strength and elongation at break of printed *** this work,a light curing system that can be applied in silicone elastomer 3D printing is explored,which is composed of vinyl terminated polysiloxane as the macromer and thiol containing polysiloxane as the crosslinking agent,and a chain extension reaction is also introduced into this light curing system via the addition of the chain extender dithiol molecules,and a light curing system accompanied with chain extension is designed and realized based on the thiol-ene click reaction *** reinforced with silica fillers,the obtained light curing system can endow the light curing silicone elastomer with better mechanical properties under the condition of a lower viscosity of the precursor,the tensile strength and elongation at break can reach 525.5 k Pa and 601%,*** light curing system provides a feasible method to solve the contradiction between the viscosity of the precursor and the mechanical properties of the light curing elastomer in the digital light processing(DLP)3D printing field.

关键词： Silicone elastomer Thiol-ene click chemistry Light curing 3D-printing Chain extender