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Journal of Renewable Materials 2023年第2期11卷 625-641页

作者： Dalong Liao Dongxu Li Shun Zhou Xiaotao Zhang Ying Fang College of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China

Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide ***,GO is easy to aggregate in alkaline cement mortar with poor *** hinders its application in practical infrastructure *** this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass *** dispersion of GM in alkaline solution was systematically *** phases and functional groups of GM were characterized by XRD and *** effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and *** results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO *** modified GO can be uniformly dispersed in the cement *** can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain *** can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical *** methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later *** provides an idea for achieving sustainability goals in civil engineering.

关键词： Modified graphene oxide cement polycarboxylate superplasticizer hydration properties me-chanical performance

Influence of High-Robustness polycarboxylate superplasticizer on the Performances of Concrete Incorporating Fly Ash and Manufactured Sand

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2041-2051页

作者： Panpan Cao Xiulin Huang Shenxu Bao Jin Yang Macheng Hubei University Research Academy of Industrial Technology Huanggang438300China Hubei Jueshuo New Material Technology Co. Ltd.Huanggang438300China School of Materials Science and Engineering Hubei UniversityWuhan430000China School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan430070China School of Civil Engineering Architecture and EnvironmentHubei University of TechnologyWuhan430068China

Using ethylene glycol monovinyl polyoxyethylene ether,2-acrylamido-2-methylpropane sulfonic acid(AMPS)and acrylic acid as the main synthetic monomers,a high robustness polycarboxylate superplasticizer was *** effects of initial temperature,ratio of acid to ether,amount of chain transfer agent,and synthesis process on the properties of the superplasticizer were *** molecular structure was characterized by GPC(Gel Permeation Chromatography)and IR(Infrared Spectrometer).As shown by the results,when the initial reaction temperature is 15℃,the ratio of acid to ether is 3.4:1 and the acrylic acid pre-neutralization is 15%,The AMPS substitution is 10%,the amount of chain transfer agent is 8%,and the performance of the synthesized superplasticizer is the *** with commercially available ordinary polycarboxylate superplasticizer in C30 concrete prepared with manufactured sand and fly ash,the bleeding rate decreases by 52%,T50 decreases by 1.2 s,and the slump time decreases by 1.1 *** C60 concrete prepared with fly ash and river sand,the bleeding rate decreases by 46%,T50 decreases by 0.8 s,and the slump time decreases by 3.2 s.

关键词： polycarboxylate superplasticizer EPEG robustness workability

Influence of polycarboxylate superplasticizer on Rheological Behavior in Cement Paste

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Journal of Wuhan University of Technology(Materials Science) 2018年第4期33卷 932-937页

作者：何燕 ZHANG Xiong KONG Yaning WANG Xiaofu SHUI Liangliang 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 Key Laboratory of Advanced Civil Engineering Materials of Education Ministry School of Material Science and TechnologyTongji UniversityShanghai 201804China Shanghai Municipal Engineering Design Institute(Group)Co. Ltd.Shanghai 200092China

Molecular structures of polycarboxylate（PCE） superplasticizer significantly affect the rheological properties of cement paste. Consequently, we employed self-synthesized PCE copolymers with different carboxylic densities to investigate their influence on the rheological behavior of cement paste. Three typical rheological models were applied to analyze the rheological properties, including Power-law model, Bingham model as well as Herschel-Buikley model. In addition, the thixotropical performances of cement paste in the presence of PCE with different carboxylic densities were investigated. The results show that the carboxylic density of PCE greatly influences the dispersing performance of PCE superplasticizers. As carboxylic density increases, the dispersing capability of PCE improves, and P（PEG1-AA6） possesses the strongest dispersing capability, the initial fluidity and 1 h fluidity of cement paste are both the highest, and cement paste has the lowest viscosity and the smallest hysteresis loop.

关键词： polycarboxylate superplasticizer carboxylic density fluidity rheology thixotropy

Synthesis and Performance Characterization of a Low Adsorption Clay-resistant polycarboxylate superplasticizer

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Journal of Wuhan University of Technology(Materials Science) 2021年第3期36卷 446-455页

作者：张营 WANG Pengshuo 孙国文 YANG Jianming GAO Rui School of Materials Science and Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China College of Civil Engineer-ing Yancheng Institute of TechnologyYancheng 224051China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China Heibei Key Laboratory of Advanced Materials for Transportation Engineering and Environment Shijiazhuang Tiedao UniversityShijiazhuang050043China

A low adsorption clay-resistant polycarboxylate superplasticizer(KN-PC)was synthesized using acrylic acid and isopentenol polyoxyethylene ether as the main reaction *** structural characterization and clay-resistant mechanism of the KN-PC were explored using Fourier transform infrared spectroscopy and X-ray diffraction,and the effect of the KN-PC on the performance of composite paste with various montmorillonite(MMT)contents was *** with ordinary polycarboxylate superplasticizer(PC),the KN-PC has a low sensitivity to the *** the action of the MMT,the adsorption dosage of the KN-PC on the MMT is much smaller than that of the PC.

关键词： polycarboxylate superplasticizer clay-resistant montmorillonite performance synthesis

Effects of Molecular Structure of polycarboxylate-type superplasticizer on the Hydration Properties of C_3S

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Journal of Wuhan University of Technology(Materials Science) 2012年第4期27卷 768-772页

作者：丁庆军 State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology

Effects of polycarboxylate-type superplasticizer（PC） molecular structure on the hydration heat of tricalcium silicate（C3S） paste and polymerization degree of hydration products（C-S-H gel） were researched by using TAM AIR isothermal microcalorimetry（TA） and 29Si nuclear magnetic resonance（NMR）.Methoxy polyethylene glycol-methacrylates-based polycarboxylate superplasticizers with different side chain lengths and main chain lengths were *** molecules with shorter main chain or longer side chains caused stronger retardation of C3S early hydration and lesser increase of C3S 3 d hydration *** measurement indicated that the incorporation of PC increased the hydration degree of C3S paste and the polymerization degree of silicon-oxygen tetrahedron of C-S-H *** tendency for C3S 7 d hydration degree to improve was more pronounced while PC molecules with longer main chain or shorter side chain were ***,PC molecules with longer main chains or longer side chains increased the 7 d polymerization degree of C-S-H gel.

关键词： tricalcium silicate polycarboxylate superplasticizer C-S-H gel hydration NMR

The Room Temperature Synthesis and Performance Study of Cationic polycarboxylate superplasticizer

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The Room Temperature Synthesis and Performance Study of Cati...

Adsorption Mechanism of polycarboxylate-Based superplasticizer in CFBC Ash-Portland Cement Paste

2016第十三届全国商品混凝土可持续发展论坛暨2016...

作者： Liang Xiaotong Zhang Wei Li Jinxia Lin Zhen Guangdong FuTe New Materials Technology Co. Ltd. Guangdong XinYe Concrete Co. Ltd.

In this paper,cationic polycarboxylate superplasticizer has been synthesized by using room temperature process with HPEG,AA,DAC and 3-S as the main raw *** investigated the effect of the dosage of different raw materials on the dispersing property of polycarboxylate superplasticizer,and we knew that AA:DAC HPEG:3-S=4.5:0.05:1:0.12 was the best molar ratio,the synthesized cationic polycarboxylate superplasticizer had excellent dispersity and mud resistance,and it was superior to commercially available ordinary polycarboxylate superplasticizer

关键词： polycarboxylate superplasticizer cationic room temperature process concrete admixture

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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 945-949页

作者：宋远明 GUO Chuanchuan QIAN Jueshi LIU Yiquan CAO Aizhi School of Environmental and Materials Engineering Yantai University School of Materials Science and Engineering Chongqing University School of Civil and Environmental Engineering Nanyang Technological University

Circulating fluidized bed combustion （CFBC） ash exhibits the desirable pozzolanic activity which makes it a potential supplementary cementitious material to replace cement for concrete production. However, the high unburnt carbon content and porous surface structure of CFBC ash may adsorb water reducer and thereby significantly reduce the efficiency of water-reducing agents. The adsorption mechanism of polycarboxylate superplasticizer in CFBC ash-Portland cement paste was investigated by ultraviolet-visible spectrophotometer, and the conception of ＂invalid adsorption site＂ of CFBC ash was presented. The results show that the adsorption behavior of polycarboxylate superplasticizer in coal ash-Portland cement paste can be described by Langmuir isothermal adsorption equation. The adsorption capacity of CFBC ash-Portland cement paste is higher than that of pulverized coal combustion （PCC） fly ash-Portland cement paste. Moreover, the adsorption amount of polycarboxylate superplasticizer increases with the ratio of ash-to-cement in the paste. At last, the fluidity of CFBC ash-Portland cement paste is lower than that of the PCC fly ash paste. This work suggests that when CFBC ash is used as concrete admixture, the poor flowability of the cementitious system due to the high adsorption of water and water-reducing agent should be taken into consideration.

关键词： CFBC ash concrete admixture adsorption polycarboxylate superplasticizer invalid adsorption site

Effects of the chemical structure of polycarboxylate-type superplasticizer on the hydration properties of C3S

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Effects of the chemical structure of polycarboxylate-type su...

An alternative approach to improve the compatibility of PCE in cement paste blend with coal gangue powder

2011中国材料研讨会

作者： DING Qingjun,WNAG Yu,HUANG Xiulin,GONG Zicheng,ZHU Yuxue

By using isothermal microcalorimetry,NMR,the effects of the chemical structure of polycarboxylate-type superplasticizer （PC） on the hydration behavior of tricalcium silicate （C 3 S） paste were *** experimental synthesized superplasticizers have been varied by polycarboxylate copolymers with different side chain lengths and main chain *** effects on hydration heat and microstructure of hydration products C-S-H gel were *** results show that:PC molecules with short main chains retarding the hydration and decreasing the heat release of C 3 *** PC molecules with long side chains have the same ***,NMR measurement indicates that PC changes the polymerization state of silicon-oxygen tetrahedron of C-S-H *** degree of polymerization is increased after C 3 S incorporating ***,the longer main chains of PC molecules,the higher degree of polymerization of C-S-H gel,while the shorter side chains have similar effects.

关键词： tricalcium silicate polycarboxylate superplasticizer C-S-H gel

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Waste Disposal and Sustainable Energy 2024年第1期6卷 139-150页

作者： Zonglin Xie Yuxuan Li Dahui Sun Yi Tian Jinyuan Hu Qiang Yuan Zheng Chen School of Civil Engineering Central South UniversityChangshaChina China Railway NO.9 Group CO. LTDShenyangChina National Engineering Research Center for High-Speed Railway Construction Technology ChangshaChina Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanningChina

Coal gangue(CG)is an environmental waste that faces an urgent demand for disposal in *** utilization of CG in construction materials has broad application prospects and gained increasing ***,the poor compatibility of polycarboxylate superplasticizer(PCE)with CG powder hinders its efficiency in a wide range of ***,this paper attempts to improve the compatibility of PCE with CG powder in cement paste based on the regulation of aggregation and the adsorption behavior of *** light scattering(DLS)and fluorescence spectroscopy tests were carried out to understand the improved *** results indicated that the addition of CG powder increases the ionic strengths of the cement liquid phase,which makes PCE tend to aggregate at a lower concentration compared with no CG powder ***(CH_(3)COO)_(2)Cu is beneficial for enhancing the workability of cement paste by reducing PCE aggregation while maintaining the compressive strength of cement ***,(CH_(3)COO)_(2)Cu extra addition can be regarded as an effective and sustainable way to improve the workability of cement paste with CG powder.

关键词： Coal gangue powder polycarboxylate superplasticizer Compatibility Aggregation

Influences of polycarboxylate superplasticizers on Rheological Behavior of Low-cement Castables

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China's Refractories 2013年第2期22卷 33-37页

作者： LI Zhukai HE Tingshu HUANG Xiaoyan College of Material & Mineral Resources Xi'an University of Architecture and Technology Sichuan College of Architectural Technology

Influences of different superplasticizers （ STP. KSJSTO and LMS-P） on rheological behavior of low-cement castables and the mechanisms were analyzed. The shear stress and viscosity under different shear rates of matrix slurry were determined using a NXS-I IA rotary viscometer. Effects of different admixtures on the rheological properties of slurry was analyzed theoretically. Sodium tripolyphosphate and poly＇carboxylate superplasticizers KS-JSTO and LMS-P） can improve the fluidity and initial setting time. With STP. the slurry is plastic flow. With KS-JS70 or LMS-P increasing, the slurrv changes from ***, pseudoplastic flow to dilatant flow successively. Th, e optimum dosages of STP. KS-JSTO and LMS-P are 0. 15%. 0. 25% and 0. 40%, respectively. KS-JS70 and LMS-P can significantly reduce the slurry viscosity and shear stress to improve the workability of construction. Both shear stress and viscosity shall be taken into account for on-site construction.

关键词： polycarboxylate superplasticizer theological behavior apparent viscosity shear stress