Influence of fluoride ion on the performance of PCE in hemihydrate gypsum pastes
Influence of fluoride ion on the performance of PCE in hemihydrate gypsum pastes
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DOI：
10.1016/j.jobe.2021.103582
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发表时间：
2021-11
影响因子：
6.4
通讯作者：
Huahui Qi;B. Ma;H. Tan;Ying Su;Wenda Lu;Zihao Jin
中科院分区：
文献类型：
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作者：
Huahui Qi;B. Ma;H. Tan;Ying Su;Wenda Lu;Zihao Jin
磷石膏中的杂质对磷石膏的性质和掺合料的性能有很大的影响。研究了氟离子（F −）对半水石膏浆体中聚羧酸减水剂（PCE）性能的影响。通过在天然半水石膏-PCE体系中引入F −，系统研究了其工作性、力学性能和水化过程。结果表明，F −对PCE增塑半水石膏浆体的流动性有负面影响。此外，F-显着降低了凝固时间，无论PCE的存在或不存在。结果表明，低溶解度的CaF2优先于CaSO4·2H2O生成，并作为晶核促进半水石膏的水化。PCE在CaF2表面的吸附行为消耗了PCE，导致分散能力下降。
Impurities in phosphogypsum have a significant impact on its properties and the performance of admixture. This study aims to reveal the influence of fluoride ion (F−) on the performance of polycarboxylate superplasticizer (PCE) in hemihydrate gypsum pastes. By introducing F−into the natural hemihydrate gypsum - PCE system, workability, mechanical properties, and hydration process were systematically studied. The results showed that F−had a negative effect on the fluidity of PCE plasticized hemihydrate gypsum pastes. Moreover, F−significantly reduced the setting time regardless of the presence or absence of PCE. It was found that CaF2with low solubility was preferentially formed to CaSO4⋅2H2O and served as nuclei to promote the hydration of hemihydrate gypsum. The adsorption behavior of PCE on the surface of CaF2consumed PCE, resulting in the decline of dispersion ability.