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

论文摘要

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.

论文目录

• 1 Introduction
• 2 Experimental
•   2.1 Materials
•   2.2 Synthesis and purification of PCEs
•   2.3 Measurements on cement paste
•     2.3.1 Fluidity and rheological properties of cement paste
•     2.3.2 Adsorption amount
•     2.3.3 Hydration properties analysis
• 3 Results and discussion
•   3.1 Effects of different PCEs on rheological performance of cement paste
•     3.1.1 Fluidity of cement paste
•     3.1.2 Viscosity and yield stress of cement paste
•   3.2 Adsorption behavior of different PCEs
•   3.3 Effects of different PCEs on cement hydration process
• 4 Conclusions

文章来源

类型: 期刊论文

作者: 何燕,ZHANG Xiong,WANG Yiting,KONG Yaning,JI Tao,SHUI Liangliang,WANG Xiaofu,WANG Haoren

来源: Journal of Wuhan University of Technology(Materials Science) 2019年05期

年度: 2019

分类: 工程科技Ⅰ辑,工程科技Ⅱ辑

专业: 无机化工,建筑科学与工程

单位: School of Civil Engineering, Suzhou University of Science and Technology,State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology,State Key Laboratory of Green Building Materials, China Building Materials Academy,Key Laboratory of Advanced Civil Engineering Materials of Education Ministry, Tongji University,School of Architecture and Engineering, Nanjing Institute of Technology,Shanghai Municipal Engineering Design Institute(Group) Co., Ltd.

基金: Funded by the National Natural Science Foundation of China(No.51808369),the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.18KJB560016),the Opening Project of State Key Laboratory of Green Building Materials(No.YA-615),the State Key Laboratory of Silicate Materials for Architectures(No.SYSJJ2018-09),Science and Technology Project of Jiangsu Provincal Department of Housing and Urban-Rural Construction(No.2018ZD049),the Natural Science Foundation of Suzhou University of Science and Technology(No.XKQ2018009)

分类号: TQ172.1

页码: 1163-1169

总页数: 7

文件大小: 1198K

下载量: 7