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SYNTHESIS, CHARACTERIZATION AND BIOLOGICAL ACTIVITY OF POLYKETONES

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Chinese Journal of polymer Science 2013年第3期31卷 471-480页

作者： Ismail A.Alkskas Altaher M.Alhubge Faizul Azam polymer lab Department of ChemistryFaculty of ScienceMisurata University Department of Microbiology Faculty of ScienceMisurata University Faculty of Pharmacy Misurata University

Polyketone resins have been prepared by the Friedel-Crafts polymerization of dithiophenylidenecyclopentanone （I）, dithiophenylidenecyclohexanone （II） and dithiophenylideneacetone （III） with adipoyl, sebacoyl and terephthaloyl dichlorides using boron trifluoride as catalyst and carbon disulphide as solvent. polymers were characterized with IR, 1H- NMR, and the results showed the presence of carbonyl of ketonic groups in the main chain. The polyketones have inherent viscosities of 0.40-0.70 dL/g. All the polymers are semicrystalline and most of them are partially soluble in most common organic solvents but freely soluble in aprotic solvents. The temperatures of 50% weight loss are as high as 185℃ to 280℃ in air, indicating that these aromatic polyketones have excellent thermal stability. All the polyketones were tested for their antimicrobial activity against bacteria and fungi.

关键词： Synthesis Characterization Polyketones Biological activity.

Thermally Conductive,Healable Glass Fiber Cloth Reinforced polymer Composite based onβ-Hydroxyester Bonds Crosslinked Epoxy with Improved Heat Resistance

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Chinese Journal of polymer Science 2024年第5期42卷 643-654,I0009页

作者： Fang Chen Xiao-Yan Pang Ze-Ping Zhang Min-Zhi Rong Ming-Qiu Zhang Key laboratory for polymeric Composite and Functional Materials of Ministry of Education GD HPPC LabIGCMESchool of ChemistrySun Yat-sen UniversityGuangzhou510275China Guangdong Provincial laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Jieyang515200China

To simultaneously endow thermal conductivity,high glass transition temperature(Tg)and healing capability to glass fiber/epoxy(GFREP)composite,dynamic crosslinked epoxy resin bearing reversibleβ-hydroxyl ester bonds was reinforced with boron nitride nanosheets modified glass fiber cloth(GFC@BNNSs).The in-plane heat conduction paths were constructed by electrostatic self-assembly of polyacrylic acid treated GFC and polyethyleneimine decorated ***,the GFC@BNNSs were impregnated with the mixture of lower concentration(3-glycidyloxypropyl)trimethoxysilane grafted BN micron sheets,3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate and hexahydro-4-methylphthalic anhydride,which accounted for establishing the through-plane heat transport pathways and avoiding serious deterioration of mechanical *** resultant GFREP composite containing less boron nitride particles(17.6 wt%)exhibited superior in-plane(3.29 W·m^(-1)·K^(-1))and through-plane(1.16 W·m^(-1)·K^(-1))thermal conductivities,as well as high Tg of 204℃(Tg of the unfilled epoxy=177℃).The reversible transesterification reaction enabled closure of interlaminar cracks within the composite,achieving decent healing efficiencies estimated by means of tensile strength(71.2%),electrical breakdown strength(83.6%)and thermal conductivity(69.1%).The present work overcame the disadvantages of conventional thermally conductive composites,and provided an efficient approach to prolong the life span of thermally conductive GFREP laminate for high-temperature resistant integrated circuit application.

关键词： Thermally conductive composites Boron nitride High-temperature resistance β-Hydroxyl ester bond Healing

Dynamic Sulfur-Rich polymers from Elemental Sulfur and Epoxides

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Chinese Journal of polymer Science 2024年第10期42卷 1479-1487,I0010页

作者： Ke-Xiang Chen Chen-Hui Cui Zhen Li Ting Xu Hao-Qing Teng Zhi-Yuan He Yin-Zhou Guo Xiao-Qing Ming Zhi-Shen Ge Yan-Feng Zhang Tie-Jun Wang School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China State Key lab for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an710049China

Sulfur-containing dynamic polymers had attracted significant attention due to their unique chemical structures with high *** sulfur, an inexpensive industrial waste product, to synthesize dynamic polysulfide polymers through reverse vulcanization has been a notable approach. However, this method required high temperatures and resulted in the release of unpleasant oders. In this study, we presented a robust method for the preparation of sulfur-rich polymers with dynamic polysulfide bonds from elemental sulfur and inexpensive epoxide monomers via a one-pot strategy at the mild room temperature. Different types of polysulfide molecules and polymers were synthesized by reacting various epoxide compounds with sulfur, along with the investigation of their structures and dynamic behaviors. It was noteworthy that the obatined polymers prepared from m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl)aniline and elemental sulfur exhibit multiple dynamic behaviors, including polysulfide metathesis and polysulfide-thiol exchange, enabling their rapid stress relaxation, self-healing, reprocessing and degradable properties of the cross-linked polymer. More importantly, the hydroxyl groups at the side chains from epoxide ring opening exhibited potential transesterification. This work provided a facile strategy for designing dynamic sulfur-rich polymers via a mild synthesis route.

关键词： Elemental sulfur Sulfur-containing polymer Dynamic covalent bond Dynamic polymer

Simultaneous enhancement of efficiency and stability of OLEDs with thermally activated delayed fluorescence materials by modifying carbazoles with peripheral groups

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Science China Chemistry 2019年第3期62卷 393-402页

作者： Yunge Zhang Dongdong Zhang Taiju Tsuboi Yong Qiu Lian Duan Key lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Department of polymer Science and Engineering Zhejiang University

Albeit their high efficiencies, the operational stability of the organic light emitting diodes(OLEDs) based on thermally activated delayed fluorescence(TADF) emitters is still far from satisfaction, and few strategies have been proposed to improve their stability. Here, we show that by modifying the carbazole unit, one of the most commonly used donors in TADF emitters, with peripheral groups, both the device efficiency and operational stability can be greatly improved. Awell-known TADF molecule—4,5-di(9H-carbazol-9-yl)phthalonitrile(2CzPN) was chosen as the prototype and modified by introducing peripheral tert-butyl and phenyl groups to the 3,6-positions of the carbazole(named 2tBuCzPN and 2PhCzPN, respectively). The introduced groups not only improve the compounds' electrochemical stabilities referred to the cyclic voltammetry multi-sweep results, but also promote their photoluminescence quantum yields. Furthermore, reduced singlet-triplet energy gaps are observed, leading to the shortened exciton lifetimes which are benefit to suppress the exciton annihilations. Besides, the steric hindrance of introduced phenyl groups can partly restrain the concentration quenching of the TADF emitter. Consequently, OLEDs based on 2tBuCzPN and 2PhCzPN achieved improved maximum external quantum efficiencies(EQEs) of 17.0% and 14.0%, respectively(compared to 8.5% for 2CzPN). Meanwhile, 2PhCzPN based OLED showed reduced roll-off characteristics and a longer lifetime of 7.8 times higher than that of 2CzPN, testifying the effectiveness of subtle modification of the unstable moieties in simultaneous enhancement of efficiency and stability of OLEDs based on TADF emitters.

关键词： TADF OLED stability carbazole peripheral group

Synergistic enhancement of chemotherapy for bladder cancer by photothermal dual-sensitive nanosystem with gold nanoparticles and PNIPAM

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Chinese Chemical Letters 2024年第8期35卷 471-474页

作者： Xiangqian Cao Chenkai Yang Xiaodong Zhu Mengxin Zhao Yilin Yan Zhengnan Huang Jinming Cai Jingming Zhuang Shengzhou Li Wei Li Bing Shen Department of Urology Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Department of Nanomedicine&Shanghai Key lab of Cell Engineering Naval Medical UniversityShanghai 200433China

Bladder cancer is a common malignant tumor of the urinary system with the potential to be treated by nano drug delivery *** current work describes the synthesis and characterization of a novel nanomaterial to construct a nano-carrier based on 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatecholine(POPC)loaded doxorubicin(DOX)and embedded with gold nanoparticles and poly(N-isopropyl acry-lamide)(PNIPAM)(GNPS@PNIPAM-POPC-DOX,GPPD).The dual-sensitive nanosystem gives simultaneous photothermal treatment and chemotherapy for bladder *** vitro and in vivo properties were as-sessed using bladder cancer cell lines and mice and GPPD system distribution,tumor inhibition,and biocompatibility are *** system had favorable stability,low biological toxicity,controlled re-lease efficiency,photothermal synergistic action,efficient photothermal transition,and favorable tumor suppressive *** a result,GPPD is a potential therapeutic approach for bladder cancer.

关键词： Doxorubicin Gold nanoparticles Thermosensitive polymer Photothermal therapy Bladder cancer

A theoretical model for impact protection of flexible polymer material

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 217-226页

作者： Huifeng Xi Hui Pan Song Chen Heng Xiao MOE Key lab of Disaster Forecast and Control in Engineering School of Machanics and Construction EngineeringJinan UniversityGuangzhou 510632China Doctor Workstation of Xuwen County Guangdong Hydropower Energy Co. Ltd.Xuwen 524100China

The relationship between the protective performance of flexible polymer material and material parameters(elasticmodulus,viscosity coefficient)is explored,an impact collision motion equation between two bodies is establishedfrom the viscoelastic material constitutive,and the relationship between the kinematic response and the materialparameters is *** on the Kelvin constitutive model,a theoretical model for impact between the pro-tective body and the protected body is established,then the dynamic response is *** feasibility of themodel was verified by drop hammer experiment,and the material parameters(elastic modulus,viscosity coeffi-cient)were obtained by *** model is discretized and the relationship between local impact response andmaterial parameters is *** discussion results on the relationship between the impact response and theprotective material performance indicate that adjusting the elastic modulus,viscosity coefficient,and thicknessof the protective material can effectively improve protective effect.

关键词： Flexible polymer material Viscoelastic material Kelvin modelDynamic response Elastic modulus and viscosity coefficient

One-pot synthesis of hyperbranched poly(amido amine) clicked with a sugar shell via Michael addition polymerization and thiol click reaction

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Science China Chemistry 2010年第8期53卷 1663-1668页

作者： YU ZhiQiang,CUI MengMeng,YAN JunJie & YOU YeZi CAS Key lab of Soft Matter Chemistry Department of polymer Science and Engineering,University of Science and Technology of China,Hefei 230026,China CAS Key lab of Soft Matter Chemistry Department of polymer Science and Engineering University of Science and Technology of China Hefei China

This paper reports the production of glycopolymers via a simple and flexible method.A novel glycopolymer with a hyperbranched poly(amido amine) core and a sugar shell (HPAA-GLc) was synthesized by using thiol-ene click reaction via facile one-pot *** poly(amido amine) with vinyl terminals was first synthesized by Michael addition polymerization of N,N'-methylene bisacrylamide (MBA) with 1-(2-aminoethyl) piperazine (AEPZ).Subsequently,thiol-ene click reaction between vinyl units of hyperbranched poly(amido amine) and thio-glucose was performed in *** on the NMR result,all the vinyl groups reacted with thiol-glucose in 120 *** photoluminescence emission was observed from the aqueous solution of HPAA-GLc.

关键词： thiol-ene click reaction glycopolymers hyperbranched poly(amido amine) photoluminescence

Redox Reaction of Disulfide/Polyaniline in Aqueous Solution

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Chinese Chemical Letters 1998年第6期9卷 523-526页

作者： Yu, L Wang, XH Li, J Jing, XB Wang, FS Chinese Acad Sci Changchun Inst Appl Chem Polymer Chem Lab Changchun 130022 Peoples R China

The cleavage and formation of the di sulfide bond of 2,5-dimercapto-1,3,4-thiadiazole (DMcT) were examined in an aqueous solution of pH value from 0 to 14 with and without polyaniline (PAn), The redox reaction of DMcT was accelerated by PAn in acidic condition. The cell using this anodic material was set-up and characterized in aqueous electrolyte.

关键词： polyaniline disulfide redox reaction

PRECISE SYNTHESIS OF OLEFIN BLOCK COpolymerS USING A SYNDIOSPECIFIC LIVING polymerIZATION SYSTEM

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Chinese Journal of polymer Science 2013年第4期31卷 541-549页

作者：蔡正国 Hai-hui Su Takeshi Shiono State Key lab for Modification of Chemical Fibers and polymer Materials College of Material Science and EngineeringDonghua University Graduate School of Engineering Hiroshima University

This feature article summarizes the synthesis of novel olefin block copolymers using fast syndiospecific living homo- and copolymerization of propylene, higher 1-alkene, and norbornene with ansa-fluorenylamidodimethyltitanium- based catalyst according to the authors＇ recent results. The catalytic synthesis of monodisperse polyolefin and olefin block copolymer was also described using this living system.

关键词： Single-site catalyst Propylene Norbomene Living polymerization Block copolymer.