预制聚合物微球对低结率的水泥复合材料与精细回收聚合物的抗性能的影响
Maja Kępniak1, Rafał Panek2, Maciej Kalinowski1
1Department of Building Materials Engineering, Faculty of Civil Engineering, Warsaw University of Technology, Al. Armii Ludowej 16, 00-637 Warsaw, Poland.
Materials (Basel, Switzerland)
|December 11, 2025
概括
预制的聚合物微球最初提高了低合物水泥复合材料的抗性. 然而,空气空隙系统随着时间的推移而降解,导致长期耐用性损失,使它们不适合仅仅提高结解的抗性.
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.
- 混凝土技术 混凝土技术
背景情况:
- 低结剂粘合剂在实现足够的抗性方面存在挑战.
- 传统的空气吸附剂 (AEA) 在这些系统中通常是无效的.
- 探索增强冷解耐久性的替代方法至关重要.
研究的目的:
- 研究预制聚合物微球 (PPM) 的使用,作为AEA的替代品,用于提高低凝复合材料的抗性.
- 评估PPM对可加工性,强度,孔隙结构和冷解耐久性的影响.
- 评估PPM创建的空气空洞系统的长期性能和稳定性.
主要方法:
- 用低结剂与飞灰和磨砂颗粒高炉渣 (GGBFS) 制备了水泥复合材料.
- 自然沙子被部分用精细的回收聚合物取代.
- 用作参考,AEA和PPM混合物的可加工性,压力强度,孔隙结构 (使用MIP) 和抗解 (经过100个周期) 被评估.
主要成果:
- 与基准相比,PPM的添加导致28天后压力强度增加25%.
- 最初,PPM创建了离散的空隙,改善了早期的结解能力.
- 然而,随着时间的推移,水化产品填补了这些空隙,导致空气空隙系统的损失,并在100次循环后显著降低强度 (75%的曲,35%的压缩).
- 在100个循环后,AEA混合物显示出有限的强度损失 (6%压缩).
结论:
- 预制的聚合物微球可以提升早期冷解性能,但在用回收聚合物制成的低度水泥复合材料中不能提供可靠的长期耐用性.
- 通过水化产品逐步填充空隙,使PPM的最初好处无效.
- 传统的吸入空气的添加剂仍然是确保这些材料长期耐的更有效的解决方案.
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