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Frontiers of Structural and Civil Engineering 2022年第4期16卷 506-514页

作者： Jinyoung YOON Byoung Il CHOI Jae Hong KIM Department of Structural Engineering Research Korea Institute of Civil Engineering and Building Technology(KICT)Goyang 10223Republic of Korea System Safety Research Department Korea Shipbuilding and Offshore EngineeringSeongnam 13591Republic of Korea Department of Civil and Environmental Engineering Korea Advanced Institute of Science and TechnologyDaejeon 34141Republic of Korea

The cement dispersion performance of a polycarboxylate(PCE)-based superplasticizer is highly related to their adsorption behaviors as a function of *** study evaluated effects of PCEs on rheological properties of cementitious ***,characteristics of PCEs were characterized via permeation chromatography(GPC)and Fourier-transform infrared spectrometry(FT-IR).The adsorption behavior of single and blended PCEs on cementitious composites was identified using total organic carbon analyzer(TOC).Based on the measurement of PCE adsorption,the changes of rheological properties of cementitious materials as well as the number of dispersed cement particles were characterized using a rheometer and laser spectroscopy,*** experimental results support the systematic mechanism of PCE adsorption,cement dispersion,and the decrease in viscosity of cementitious materials.

关键词： adsorption polycarboxylate superplasticizer rheology dispersion

Synthesis of a Novel polycarboxylate Superplasticizer with Carboxyl Group as Side Chain Terminal Group to Enhance Its Clay Tolerance

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 226-232页

作者：陈刚雷家珩 DU Yong CHEN Xuebing School of Materials Science and Engineering Wuhan University of Technology Wuhan New Green Boen Technology Co. Ltd School of Chemistry Chemical Engineering and Life Science Wuhan University of Technology

The dispersion ability of polycarboxylate superplasticizer（PCE） in fresh concrete was much impeded by clay impurities. To improve the dispersion of PCE in the clay-contained concrete, a novel PCE with carboxyl as a specific branched chain terminal group was synthesized, using modified polyether as the raw material which was prepared through esterification between hexahydrophthalic anhydride（HHPA） and isobutenyl polyoxyethylene ether（IPEG） with hydroxy as the terminal group. The esterification product and PCE molecular structure were characterized by infrared spectroscopy and ~1HNMR resonance. The results confirmed that the product molecular structure was a comb-type copolymer with long-chain terminal carboxyl group and PEO attached directly to the backbone chain. The as-synthesized PCEs had favorable dispersibility in cement than conventional PCE in the presence of montmorillonite（Mmt） clay. This can be attributed to the introduction of electronegative carboxyl to PCE long-chain terminal group, which reduces the adsorption of PCE on Mmt, and thus improves the tolerance of PCE to the Mmt.

关键词： polycarboxylate clay cement

Synthesis of New Polyether polycarboxylate Superplasticizer

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 799-802页

作者：麻秀星 Materials College Chongqing University Xiamen Academy of Building Research Group

The effects of various factors on the synthesis process and the performances of product, including batch feeding way and the dosage of the radical initiator, the system concentration, the reaction temperature and the reaction time were discussed. A kind of polycarboxylate superplasticizer with allyl alcohol polyethylene glycol, maleic anhydride and methacrylic acid sulfonic sodium as main raw materials has been synthesized. Their relative effectiveness as dispersants was evaluated in cement paste by measuring paste fluidity. The optimum parameters of technology and the appropriate proportion of raw materials were obtained. As a result,the new high performance superplasticizer suitable for high-performance concrete has been synthesized. The structure of copolymer was characterized and analyzed by FT-IR spectra. Results indicated that product copolymer structure was consistent with the ideal molecular structure designed.

关键词： polycarboxylate maleic anhydride high-performance superplasticizer free radical polymerization

Preparation and Characterization of a New Kind of Nano-rod Shaped polycarboxylate Slump-Retaining Admixture Using for Concrete

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Journal of Shanghai Jiaotong university(Science) 2012年第5期17卷 541-544页

作者：段国荣黄国泓李爱梅祝烨然龚英 Research Center on New Materials in Hydraulic Structures of Ministry of Water Resources Nanjing Hydraulic Research Institute Nanjing R&D High Technology Co.Ltd.

A new kind of nano-rod shaped polycarboxylic acid slump-retaining agent was *** electron microscope(TEM) experiment showed that the nano-rod was bound together as macromolecular aggregates in *** performance studying suggested that this kind nano-sized polymer material had excellently plasticity-retaining performance in cement-based materials and could improve endurance performance of hardened cement-based materials *** concrete with an initial slump of 2-9 cm could achieve 3 h plasticity-retaining performance with the help of this kind *** product had extremely wide application value in the market.

关键词： nano-material polymer concrete polycarboxylate slump-retaining admixture

Three Ni（II） Coordination Polymers with Various Architectures Based on Asymmetric Bis-pyridyl-amide and polycarboxylates： Syntheses, Structures and Properties

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Chemical Research in Chinese Universities 2016年第5期32卷 719-724页

作者： WU Xiaomei LIU Guocheng WANG Xiuli SHAO Jiyan LIN Hongyan WANG Xiang Department of Chemistry Liaoning Province Silicon Materials Engineering Technology Research Centre Bohai University Jinzhou 121000 P. R. China

Three different dimensionalNi（II） coordination polymers, [Ni（3-pna）（HIP）（H2O）3]-H20（1）, [Ni（3-pna）- （1,3,5-HBTC）]（2） and [Ni2（H2O）（3-pna）2（1,4-CHDC）2]4（3）（3-pna=3-pyridylnicotinamide, H2HIP=5-hydroxyisoph- thalic acid, 1,3,5-H3BTC=l,3,5-benzenetricarboxylic acid, 1,4-H2CHDC=l,4-cyclohexanedicarboxylic acid）, were synthesized under hydrothermal conditions and characterized by means of infrared spectra（IR）, thermal gravimetric （TG） analyses, powder X-ray diffraction（PXRD） and single-crystal X-ray diffraction. Complex 1 has a structure of 1D single-stranded chain, which is further stretched by hydrogen-bond interactions to form a 2D supramolecular sheet. Complex 2 shows a 2D network, which is stretched to 3D supramolecular frameworks through hydrogen-bond interactions. Complex 3 reveals a 3D skeleton with a （3,3,6,6）-connected {3·72} {32·4 } {33·42·5·73·85·9 } {33·45·52·72·82·9} topology. The effects of different polycarboxylates on the ultimate architectures of the complexes 1--3 were dis- cussed. Furthermore, the fluorescent and photocatalytic properties of the title complexes were also investigated.

关键词： Crystal structure Dipyridylamide polycarboxylate Photoluminescence property Photocatalytic property

Effect of PCEs with Different Functional Groups on the Performance of Cement Paste

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1163-1169页

作者： HE Yan[[ ZHANG Xiong WANG Yiting KONG Yaning JI Tao SHUI Liangliang WANG Xiaofu WANG Haoren School of Civil Engineering Suzhou University of Science and TechnologySuzhou 215011China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Green Building Materials China Building Materials AcademyBeijing 100024China Key Laboratory of Advanced Civil Engineering Materials of Education Ministry Tongji UniversityShanghai 201804China School of Architecture and Engineering Nanjing Institute of TechnologyNanjing 211167China Shanghai Municipal Engineering Design Institute(Group)Co. Ltd.Shanghai 200092China

The adsorption behaviors and dispersing properties of polycarboxylate superplasticizer(PCE) with different functional groups were systematically analyzed to reveal the theory and methods of modifying PCE molecular structures and regulating PCE performances. By substituting carboxylic groups with sulfonic groups, ester groups or acylamino groups, respectively, modified PCEs with different functional groups were synthesized. Results show that introducing low amount of ester groups or sulfonic groups into the PCE molecules has no negative effects on the fluidity of cement paste, while introducing acylamino groups into PCE molecules significantly weakens the fluidity of cement paste. At low amount(when the molar ratio of sodium methallyl sulfonate to TPEG is lower than 0.4), the rapid adsorption of sulfonic groups onto the cement particles contributes to the high dispersing performance of the sulfonic group modified PCEs. When the substitution ratio of acrylic acid by sulfonic acid is higher than 0.4, the viscosity and the yield stress of cement paste increases sharply. Redundant sulfonic groups lead to the excessive charge density of the PCE, which contributes to the inhomogeneous adsorption on the cement grains and hence results in the decline of the dispersing performance. Substitution of carboxylic group by acylamino group or ester group slightly changes the viscosity as well as the yield stress of cement paste. Introducing sulfonic group into PCE molecule improves the adsorption behavior of PCEs, while introducing ester group or acylamino group into PCE depresses the adsorption properties.

关键词： polycarboxylate superplasticizer functional group adsorption behavior rheological properties cement hydration

Microstructural Characteristics Analysis of PCE Copolymer from Methyl Allyl Polyethylene Glycol and Methacrylic Acid based on Determination of Monomer Reactivity Ratios

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Journal of Wuhan University of Technology(Materials Science) 2021年第2期36卷 223-229页

作者： WANG Ziming KANG Yaxin PENG Jingying College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

The reactivity ratio of monomer and the microstructure of copolymer as polycarboxylate ether(PCE)superplasticizer were *** ethers(PCEs)were synthesized from methyl allyl polyethylene glycol(MAPEG,Mw=2400 g/mol)and methacrylic acid(MAA)via aqueous free radical copolymerization in low conversion(P<20%).Gel permeation chromatography(GPC)and high performance liquid chromatography(HPLC)were used to track the residual concentration of the reactants and the amount of copolymer formed during the *** reactivity ratios of monomers,MAPEG and MAA,were determined as r1(MAPEG)=0.0489 and r2(MAA)=1.6173,respectively,by employing the K-T and YBR *** to the obtained monomer reactivity results,the sequence distribution of the copolymer,the number average length of MAA in the polymerisate were found to decline with the decrease of the mole fraction of MAA in the polymerization *** a result,the distribution of chain segments becomes narrower and the copolymer structure becomes more ***,uniform polymers could be obtained by slowly adding MAA monomer during copolymerization process.

关键词： reactivity ratio polycarboxylate K-T method copolymer sequence distribution

Synthesis and Study of Novel superplasticizer

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Synthesis and Study of Novel superplasticizer

河南省化学会2016年学术年会

作者： Cheng-jun Hao guang-pu Bai College of chemistry and Environmental engineering Pingdingshan University

New High Performance polycarboxylate performance more prominent such as: high water reduction,adaptability, cost less, is an important research direction of development in the new century water reducer *** paper introduces the research development process polycarboxylate water reducer, promote the use of home and abroad, analyzes the mechanism of polycarboxylate water reducer, and the synthesis of various factors. Simple Discussion Synthesis polycarboxylate optimal conditions. In this paper, the experiment is divided into two steps to prepare high performance polycarboxylate water reducer,experimental results are as *** experimental materials acrylic acid and methoxy polyethylene glycol acrylate, prepared by orthogonal experiment methoxy polyethylene glycol acrylic acid monomer, esterification rate of solids and infrared spectra of the products were determined in general close to 50%.Introduced by the order of the individual components and add the amount of analyte in the experiment, the researchers in the various processes that monomer addition ratio of n [AA]: n [MPEGA]:n [SAS]: n [AM] = 3.75: 1.00 : 2.5: 3.75 when the AA mixed, MPEGA solution was mixed dropwise a mixture of acrylic acid and allyl sulfonate, the synthesized polycarboxylate superplasticizer plasticity and dispersion is the strongest.

关键词： polycarboxylate maleic anhydride Polyethylene glycol acrylic aci

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链段缓释型聚羧酸减水剂的制备及其性能研究

链段缓释型聚羧酸减水剂的制备及其性能研究