[1]俞晓涵,张倩倩,刘加平.聚羧酸分子量对净浆流变性能的影响[J].东南大学学报(自然科学版),2020,50(3):482-487.[doi:10.3969/j.issn.1001-0505.2020.03.010]
 Yu Xiaohan,Zhang Qianqian,Liu Jiaping.Effects of molecular weight of polycarboxylate superplasticizers on rheological properties of cement pastes[J].Journal of Southeast University (Natural Science Edition),2020,50(3):482-487.[doi:10.3969/j.issn.1001-0505.2020.03.010]
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聚羧酸分子量对净浆流变性能的影响()
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《东南大学学报(自然科学版)》[ISSN:1001-0505/CN:32-1178/N]

卷:
50
期数:
2020年第3期
页码:
482-487
栏目:
化学化工
出版日期:
2020-05-20

文章信息/Info

Title:
Effects of molecular weight of polycarboxylate superplasticizers on rheological properties of cement pastes
作者:
俞晓涵1张倩倩2刘加平1
1东南大学材料科学与工程学院, 南京 211189; 2江苏省建筑科学研究院有限公司高性能土木工程材料国家重点实验室, 南京 210008
Author(s):
Yu Xiaohan1 Zhang Qianqian2 Liu Jiaping1
1School of Materials Science and Engineering, Southeast University, Nanjing 211189, China
2State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Research Institute of Building Science, Nanjing 210008, China
关键词:
聚羧酸减水剂 分子量 水泥净浆 流变性能
Keywords:
polycarboxylate superplasticizers molecular weight cement pastes rheological properties
分类号:
TQ172
DOI:
10.3969/j.issn.1001-0505.2020.03.010
摘要:
试验研究了水泥净浆的流变曲线、颗粒堆积密实度、间隙液黏度和聚羧酸减水剂(polycarboxylate superplasticizers,PCE)的吸附量,探究了相同流动度下PCE分子量对水泥净浆流变性能的影响及其内在机理.结果表明:PCE存在一个最佳的分子量范围,使得处于该范围的PCE具有最强的分散能力.在选取的4种PCE中,重均分子量为29.582 kg/mol的PCE减水剂的分散性能最佳.由于桥接作用的存在,分子量大的PCE需要更多地吸附在水泥颗粒表面,以增大颗粒间距,使得浆体的屈服应力(流动度)基本相同.此时,浆体的剩余黏度主要受颗粒堆积密实度与固相体积分数的影响,呈现出随PCE分子量增加而逐渐降低的变化规律.
Abstract:
The effects and the underlying mechanism of molecular weight of polycarboxylate superplasticizers(PCE)on the rheological properties of cement pastes with the same flow spread were investigated by measuring the flow curves of cement pastes, particle packing density, viscosity of the interstitial PCE solution, as well as the adsorption amount. The results show that there is an optimal molecular weight range. PCE molecules with molecular weight in the range present the best dispersion property. Among the four selected PCEs, the PCE with the mass-average molecular weight of 29.582 kg/mol displays most excellent dispersion. Due to the existence of bridging, PCE with a relatively large molecular weight needs to possess larger adsorption amount on the cement surface to increase the particle separation distance, so that the yield stresses(fluidity)of the cement pastes are essentially the same. The residual viscosity of the cement paste depends primarily on the packing density of particles and the solid volume fraction, showing that it decreases with the increase of the molecular weight of PCE samples.

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备注/Memo

备注/Memo:
收稿日期: 2019-10-10.
作者简介: 俞晓涵(1996—),女,博士生;刘加平(联系人),男,博士,教授,博士生导师,liujiaping@cnjsjk.cn.
基金项目: 国家重点研发计划资助项目(2018YFC0705400)、国家自然科学基金资助项目(51578269).
引用本文: 俞晓涵,张倩倩,刘加平.聚羧酸分子量对净浆流变性能的影响[J].东南大学学报(自然科学版),2020,50(3):482-487. DOI:10.3969/j.issn.1001-0505.2020.03.010.
更新日期/Last Update: 2020-05-20