Na与Ca硫酸盐对硫氨酸合剂水解的作用
Pilar Padilla-Encinas1, Angel Palomo1, Ana Fernández-Jiménez1
1Eduardo Torroja Institute for Construction Science, National Research Council (iETcc-CSIC), 28033 Madrid, Spain.
Molecules (Basel, Switzerland)
|November 25, 2023
概括
硫氨酸 (KCSA) 的水分受硫酸盐的类型和数量的影响. 硫酸 (CaSO4) 增强机械强度,而硫酸 (Na2SO4) 可能导致长期不稳定和裂纹.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 无机化学 无机化学 有机化学
背景情况:
- 硫氨酸 (CSA) 水泥是一种水力水泥,以其快速硬化特性而闻名.
- 硫酸盐添加剂,如硫酸 (CaSO4) 和硫酸 (Na2SO4),对于控制CSA水化过程和CSA水泥的性能至关重要.
- 了解硫酸盐类型和含量的影响对于优化CSA水泥应用至关重要.
研究的目的:
- 调查不同数量 (5%和20%) 和类型 (CaSO4和Na2SO4) 的硫酸盐对硫氨酸 (KCSA) 水解的影响.
- 评估这些硫酸盐添加剂对KCSA糊的机械性能,水化动力学,反应产品和长期稳定性的影响.
主要方法:
- 机械强度的发展被评估在1,3,28和90天.
- 异热传导热量计被用来测量水合过程中的热量流和总热量释放.
- 使用X射线衍射 (XRD),差异热分析/热重力测量 (DTA/TG) 和扫描电子显微镜 (SEM) 来描述反应产品.
主要成果:
- 硫酸盐的数量和类型都显著影响了水化动力学,产品形成和机械强度的发展.
- 加硫酸 (CaSO4) 的加入对KCSA糊的机械强度产生了积极的影响.
- 硫酸 (Na2SO4) 导致pH值升高,乙化的不稳定,并促进碳化和化的降水,在晚年引起不良影响.
结论:
- 选择硫酸盐添加剂及其度是量身定制硫氨酸 (KCSA) 性能的关键因素.
- 虽然CaSO4有助于增强强度,但Na2SO4可能会导致有害的副作用,例如由于二级阶段形成和pH值变化而导致裂纹.
- 对于耐用和高性能CSA水泥材料,需要进一步研究硫酸盐修饰.
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