Application Performances and Mechanism of Polycarboxylic Acid in Different Comb-bonded Structures in High-performance Concrete
LIU Xiao1, XU Qian1, LAI Guanghong1, GUAN Jianan1, XIA Chunlei2, WANG Ziming1, CUI Suping1
1 College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124; 2 Beijing Municipal Engineering Research Institute, Beijing 100037
Abstract: The comb-type polycarboxylic acid has excellent architecture designability, providing the theoretical basis and technical support for the ecologicalization and high performance of green concrete. In this study, polyacrylic acid (PAA), hydroxymethoxy polyoxyethylene propylene glycol (HMPEPG) and amino methoxy polyoxyethylene propylene glycol (AMPEPG) were used as reactants based on the esterification and amidation reactions, and the two comb-type polycarboxylic acids (PCEs) which backbone and side chain were connected by ester bond and amide bond were synthesized, respectively. The measurements of Infrared spectroscopy (IR) and molecular weight proved the expected molecular structures. The application results showed that the PCE with ester linkage exhibited better initial fluidity of cement paste and early strength of concrete, and moreover, the PCE with amide linkage exhibited better fluidity retention of cement paste and slump flow of concrete. With respect to their different mechanism, the PCE with ester linkage behaved more stable adsorption behavior and stronger acceleration to hydration, whereas the PCE with amide linkage behaved lower surface tension and stronger ability in gas-liquid interface orientation. These two PCEs can be applied to the concretes with high early strength and high pumping requirements respectively, presenting a good promotion value and application prospect.
刘晓, 许谦, 赖光洪, 管佳男, 夏春蕾, 王子明, 崔素萍. 不同梳状键接结构聚羧酸在高性能混凝土中的应用性能和作用机理[J]. 材料导报, 2018, 32(22): 4011-4015.
LIU Xiao, XU Qian, LAI Guanghong, GUAN Jianan, XIA Chunlei, WANG Ziming, CUI Suping. Application Performances and Mechanism of Polycarboxylic Acid in Different Comb-bonded Structures in High-performance Concrete. Materials Reports, 2018, 32(22): 4011-4015.
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