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Synthesis of Alkyne-functionalized polymers via Living Anionic polymerization and Investigation of Features during the Post-“thiol-yne” Click Reaction

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Chinese Journal of polymer Science 2019年第9期37卷 841-850页

作者： Lin-Can Yang Li Han Hong-Wei Ma Pi-Bo Liu He-Yu Shen Chao Li Song-Bo Zhang Yang Li department of polymer Science and engineering School of Chemical Engineering Dalian University of Technology

"Thiol-yne" click reaction has already been widely applied in synthesis and modification of new polymer structures or novel materials due to its specific features. However, in most studies, only chain-end strategy was employed when using the di-addition feature of thiol-yne reaction, thus the in-chain di-addition strategy could endow us with a broader space to develop the synthesis of advanced polymers. Therefore, in this paper, the features of in-chain mono and di-addition were investigated when modifying the alkynefunctionalized polymers to prepare grafted polymers via thiol-yne click reaction. The results showed that it is almost impossible to obtain the in-chain di-adducts even under excess feeding of chain-end thiol-functionalized grafts, while only the in-chain mono-adducts could be obtained efficiently. Further researches investigated that the controlled grafting could be encountered when carrying out the thiol-yne click reaction between chain-end alkyne-functionalized polystyrenes and chain-end thiol-functionalized polystyrenes under proper feedings. Therefore, the effect of steric?hindrance might be the primary reason for the alternative grafting via thiol-yne click reaction between in-chain and chain-end alkyne-functionalized polymers.

关键词： Alkyne-functionalized polymers In-chain di-addition Thiol-yne click reaction Living anionic polymerization

Synthesis of crosslinked polystyrene particles by seeded batch polymerization with monomer absorption

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 153-159页

作者： Ki-Chang LEE Han-Ah WI department of polymer Science and engineering Engineering Research Institute Gyeongsang National University

A highly crosslinked, monodispersed polystyrene（PS） particle was prepared by a seeded batch dispersion polymerization with a monomer absorption method. Prior to polymerization, 1,9 lam monodispersed PS seed particles were treated under an optimum condition of monomer absorption. The effects of divinylbenzebe（DVB） concentration and polymerization temperature were examined for styrene（in PS seed）/styrene（in the second stage） mass ratio of 1：1 in the medium range of EtOH/water mass ratio of 100/0-80/20 and 2.3 μm uniform crosslinked PS particles containing 15%-20% （mass fraction） DVB were prepared at 60-70 ℃. The results show that monomer absorption before the second stage of polymerization is more effective to prepare highly crosslinked monodispersed PS particles.

关键词： crosslinked polystyrene particle seeded batch dispersion polymerization monomer absorption divinylbenzene (DVB)

SYNTHESIS OF AMPHIPHILIC COMB-SHAPED COpolymerS USED FOR SURFACE MODIFICATION OF PVDF MEMBRANES

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Chinese Journal of polymer Science 2009年第6期27卷 821-831页

作者：徐又一 department of polymer Science and engineering Zhejiang University

The synthesis of a novel amphiphilic comb-shaped copolymer consisting of a main chain of styrene-(N-(4- hydroxyphenyl) maleimide)(SHMI) copolymer and poly(ethylene glycol) methyl ether methacrylate(PEGMA) side groups was achieved by atom transfer radical polymerization(ATRP).The amphiphilic copolymers were characterized by ~1H-NMR, Fourier transform infrared(FTIR) spectroscopy and gel permeation chromatography(GPC).From thermogravimetric analysis (TGA),the decomposition temperature of SHMI-g-PEGMA is lower ...

关键词： Comb-shaped copolymer Amphiphilic Surface modification Hydrophillicity Anti-fouling property

Biodegradation of beet molasses vinasse by a mixed culture of micro organisms:Effect of aeration conditions and pH control

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Journal of Environmental Sciences 2011年第11期23卷 1823-1830页

作者： Krzysztof Lutoslawski Agnieszka Ryznar-Luty Edmund Cibis Malgorzata Krzywonos Tadeusz Miskiewicz department of bioprocess engineering Wroclaw University of EconomicsKomandorska 118/12053-345 WroclawPoland

The effect of aeration conditions and pH control on the progress and efficiency of beet molasses vinasse biodegradation was investigated during four batch processes at 38°C with the mixed microbial culture composed of Bifidobacterium,Lactobacillus,Lactococcus,Streptococcus,Bacillus,Rhodopseudomonas,and *** four processes were carried out in a shake flask with no pH control,an aerobic bioreactor without mixing with no pH control,and a stirred-tank reactor （STR） with aeration with and without pH control,*** experiments were started with an initial pH *** highest efficiency of biodegradation was achieved through the processes conducted in the STR,where betaine （an organic pollutant occurring in beet molasses in very large quantities） was completely degraded by the *** process with no pH control carried out in the STR produced the highest reduction in the following pollution measures：organic matter expressed as chemical oxygen demand determined by the dichromatic method ＋ theoretical COD of betaine （COD sum,85.5%）,total organic carbon （TOC,78.8%） and five-day biological oxygen demand （BOD 5,98.6%）.The process conditions applied in the shake flask experiments,as well as those used in the aerobic bioreactor without mixing,failed to provide complete betaine *** a consequence,reduction in COD sum,TOC and BOD 5 was approximately half that obtained with STR.

关键词： aerobic biodegradation batch process beet molasses vinasse mesophilic conditions mixed culture of microorganisms

ANIONIC SYNTHESIS OF A “CLICKABLE” MIDDLE-CHAIN AZIDE-FUNCTIONALIZED POLYSTYRENE AND ITS APPLICATION IN SHAPE AMPHIPHILES

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Chinese Journal of polymer Science 2013年第1期31卷 71-82页

作者： Kan Yue Jinlin He Chang Liu Mingjun Huang Xue-Hui Dong Kai Guo Peihong Ni Chrys Wesdemiotis Roderic P. Quirk Stephen Z. D. Cheng Wen-Bin Zhang department of polymer Science College of Polymer Science and Polymer EngineeringThe University of Akron College of Chemistry Chemical Engineeringand Materials ScienceJiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSoochow University department of Chemistry The University of Akron

＂Click chemistry＂ is, by definition, a general functionalization methodology （GFM） and its marriage with living anionic polymerization is particularly powerful in precise macromolecular synthesis. This paper reports the synthesis of a ＂clickable＂ middle-chain azide-functionalized polystyrene （mPS-N3） by anionic polymerization and its application in the preparation of novel shape amphiphiles based on polyhedral oligomeric silsesquioxane （POSS）. The mPS-N3 was synthesized by coupling living poly（styryl）lithium chains （PSLi） with 3-chloropropylmethyldichlorosilane and subsequent nucleophilic substitution of the chloro group in the presence of sodium azide. Excess PSLi was end-capped with ethylene oxide to facilitate its removal by flash chromatography. The raPS-N3 was then derived into a giant lipid-like shape amphiphile in two steps following a sequential ＂click＂ strategy. The copper（I）-catalyzed azide-alkyne cycloaddition between mPS-N3 and alkyne-functionalized vinyl-substituted POSS derivative （VPOSS-alkyne） ensured quantitative ligation to give polystyrene with VPOSS tethered at the middle of the chain （mPS-VPOSS）. The thiol-ene reaction with 1-thioglycerol transforms the vinyl groups on the POSS periphery to hydroxyls, resulting in an amphiphilic shape amphiphile, mPS-DPOSS. This synthetic approach is highly efficient and modular. It demonstrates the ＂click＂ philosophy of facile complex molecule construction from a library of simple building blocks and also suggests that mPS-N3 can be used as a versatile ＂clickable＂ motif in polymer science for the precise synthesis of complex macromolecules.

关键词： Living anionic polymerization Polyhedral oligomeric silsesquioxane (POSS) "Click" chemistry Generalfimctionalization methodology (GFM).

Polyaniline and multi-walled carbon nanotube composite electrode for rechargeable battery

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中国有色金属学会会刊：英文版 2012年第S3期22卷 717-721页

作者： Yu-Jeong LIM Min-Young PARK Sang-Keol LEE Won-Ki LEE Nam-Ju JO department of polymer Science & engineering Pusan National University Hankook Tire Co.Ltd. department of polymer engineering Pukyong National University

The multi-walled carbon nanotube was introduced into the polymer matrix (PANI) to improve the electric conductivity as well as mechanical properties of the original polymer ***/multi-walled carbon nanotube (MWCNT) composites were synthesized via ex-situ and in-situ polymerization to improve their electrical *** the DC conductivities of PANI/MWCNT according to content and diameter of MWCNT were measured by four-point *** highest electric conductivity of PANI/MWCNT composite is 20 S/cm when 0.3% (mass fraction) MWCNTs with 10 nm in diameter and 15 μm in length are added in composite.

关键词： polymer electrode electric conductivity multi-walled carbon nanotube conducting polymer

Optical Properties and Spectroscopic Parameters of Sm(DBM)_3 Doped Polymethyl Methacrylate

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Journal of Rare Earths 2004年第1期22卷 31-35页

作者：董宁陈彪尹民宁利新张其锦夏上达 Structure Research Laboratory department of polymer Science and engineering

Optical absorption spectra of Sm(DBM) 3 doped PMMA (polymethyl methacrylate) in near infrared and visible region are presented. The energy levels were assigned and analyzed in terms of the free-ion Hamiltonian model. Energy levels and reduced matrix elements calculations were carried out using the complete 198 SLJ basis sets for the 4f5 configuration. Judd-Ofelt parameters were evaluated and used to predict the radiative properties of the sample. The theoretical and experimental values for radiative lifetimes and branching ratios were discussed.

关键词： optics radiative properties Judd-Ofelt theory PMMA rare earths

Multi-walled Carbon Nanotubes as a Ligand in Nickel ?-Diimine Based Ethylene polymerization

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Chinese Journal of polymer Science 2015年第10期33卷 1389-1403页

作者： Sasan Talebnezhad Saeed Pourmahdian department of polymer engineering and Color Technology Amirkabir University of Technology

Two novel heterogeneous nickel a-diimine based polymerization catalysts, containing MWCNT as the main ligand, were synthesized by novel in situ catalyst preparation technique. The in situ synthesis was performed by covalent attachment of the acenaphthenic ligand core to amine functionalized MWCNT ligand arms through diimine bonding and further nickel dibromide chelation. The prepared catalysts were fully characterized and their structures and supporting efficiencies were determined. Single or double introduction of the MWCNTs through their ends or sidewall（s） in the catalytic system, as a ligand, influenced the catalytic performance, microstructure and morphology of obtained polyethylenes. MWCNT sidewall bonding to para-aryl position of the tetramethylphenyl moiety performed as more electron-donating ligand than MWCNT ends linked to the imine bond and protected the catalytic system to retain its activity. This character resulted in the maintenance of the resulting polymer topology at elevated temperatures so that the catalytic activity and the obtained polymer melting points remained around 110 g PE·mmol^-1 Ni·h^-1 and 123 ℃ in all polymerization temperatures respectively. In polymerization trials, molecular weight fall against temperature was not as sharp as what had been observed in sequentially prepared catalysts insofar as the molecular weight of resultant polymer at 60 ℃ reached to 310000 g·mol^-1 which was close to the highest value had been reported at 30 ℃ for sequentially prepared catalysts. TEM observations showed the presence of the stopped-growth polymer chains due to geometrical constrains or ligand debonding for both catalytic systems.

关键词： a-Diiminonickel catalyst Ligand Multi-walled carbon nanotubes Ethylene polymerization In situ catalyst preparation.

PHOTOINITIATED CROSSLINKING OF EPDM/INORGANIC FILLER BLENDS AND CHARACTERIZATION OF RELATED PROPERTIES

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Chinese Journal of polymer Science 2010年第1期28卷 119-127页

作者：瞿保钧 department of polymer Science and engineering University of Science and Technology of China

Photoinitiated crosslinking of ethylene-propylene-diene terpolymer （EPDM） blends filled with calcium carbonate, talc and calcined kaolin （CK） in the presence of benzil dimethyl ketal as photoinitiator and trimethylolpropane triacrylate as crosslinker and their related properties have been studied by different analytical methods, The results from gel content and heat extension determination show that the efficiency ofphotocrosslinking of EPDM increases with increasing the content of diene and its molecular weight. The EPDM blends with 100 phr different inorganic fillers can be photocrosslinked to gel content of above 60% by 5 s UV-irradiation under optimum conditions. Under the same conditions of irradiation, the orders of photocrosslinking rate and final gel content are EPDM/CaCO3 〉 EPDM/talc 〉 EPDM/CK. The data from thermogravimetric analysis, dynamic mechanical thermal analysis, electrical properties, mechanical tests and scanning electron microscopy show that UV irradiation crosslinking apparently enhances the thermal stability, mechanical properties and electrical properties of the photocrosslinked EPDM/inorganic filler samples. Although the attenuated total-reflection FTIR data show that inorganic fillers can promote the surface photo-oxidation of EPDM/inorganic filler samples with increasing the irradiation time, the above related properties of the photocrosslinked EPDM blends irradiated within 5 s are enough to satisfy many applications in the cable industry.

关键词： Photocrosslinking Ethylene-propylene-diene terpolymer Inorganic filler Benzil dimethyl ketal Trimethylolpropane triacrylate.