碳改性水泥的低场NMR:分散和水合研究研究
Mihai M Rusu1,2, Karoly Mostis1,2, Codrut Costinas3,4
1Department of Physics and Chemistry, Technical University of Cluj-Napoca, 400114 Cluj-Napoca, Romania.
Materials (Basel, Switzerland)
|February 13, 2026
概括
这项研究使用NMR放松计来了解碳黑 (CB) 和超塑性化剂 (SP) 如何影响水化和微观结构. 结果显示,SP延迟了水合并提炼了孔隙网络,有助于CB在水泥材料中的分散.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 土木工程 土木工程是指土木工程.
背景情况:
- 了解水化水泥对于开发先进的水泥材料至关重要.
- 碳基填充剂和超级增塑剂是影响水泥性能的关键组成部分.
- 需要使用非破坏性技术来实时评估填充剂的分散和水分.
研究的目的:
- 研究碳黑 (CB) 和烯酸超可塑剂 (SP) 对水化和水泥微观结构的影响.
- 提供基于NMR的洞察力,了解CB在水泥材料中的分散.
- 为了全面分析,将NMR发现与其他表征方法相关联.
主要方法:
- 低场NMR放松计 (in situ和ex situ) 用于监测水泥水化和CB分散.
- 动态光散射 (DLS) 和z电位测量评估了CB/SP混合物的体稳定性.
- 光学显微镜 (OM) 和超声波脉冲速度 (UPV) 用于对硬化样品的补充分析.
主要成果:
- 核磁共振成功地将碳墨水信号与水泥糊信号区分开来,使CB分散的非破坏性评估成为可能.
- 超级塑化剂 (SP) 的添加被证明可以延迟水泥的水化,并改进孔网.
- 随着SP剂量的增加,观察到CB粒子分散的改善,NMR和UPV证实了这一点.
结论:
- 核磁共振放松计是一种强大的工具,用于非破坏性地评估新鲜水泥糊中的碳基填充剂分散.
- 超级可塑剂在控制水泥水化动力学和改善添加剂分散方面发挥着重要作用.
- 结合使用NMR,DLS,z-potential,OM和UPV,提供了一个强大的方法来表征水泥材料.
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