超分支酸聚碳酸超增塑剂对降低水泥糊粘度的影响和机制
Jing Chen1, Changhui Yang2, Yan He2
1College of Materials Science and Engineering, Chongqing University, Chongqing 400030, China.
Materials (Basel, Switzerland)
|April 27, 2024
概括
超分支聚碳酸超塑化剂 (PCEs) 在较低的水与水泥比率下显示出更好的水泥分散. 较厚的吸附层增强了自由水,降低了粘度并提高了分散性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 土木工程 土木工程是指土木工程.
背景情况:
- 聚碳酸超可塑剂 (PCE) 对混凝土的性能至关重要.
- 了解新型PCE架构的吸附行为和分散能力对于优化混凝土混合物至关重要.
- 超分支结构与传统的状聚合物相比,具有独特的特性.
研究的目的:
- 研究高分支聚酸超塑性化剂 (PCE) 的吸附行为和分散能力.
- 探索聚合物架构,特别是含酸单和二的超分支结构对水泥分散的影响.
- 阐明在水泥糊中提高分散性和降低粘度背后的机制.
主要方法:
- 自由基溶液聚合,以合成具有量身定制架构的超分支PCE.
- 在聚合物骨干中改变酸单和酸二的含量.
- 动态光散射 (DLS) 和传输电子显微镜 (TEM) 用于分析吸附层厚度.
- 评估不同水与水泥比率 (w/c) 的分散能力.
主要成果:
- 超分支的PCE在较高的w/c (0.29) 时表现出比状PCE更弱的分散.
- 然而,超分支的PCE在较低的w/c时表现出优越的分散能力.
- 与状PCE相比,DLS和TEM分析显示,高分支PCE的吸附层比状PCE更厚.
- 更厚的吸附层导致更薄的扩散水层,增加了自由水含量.
结论:
- 通过超分支PCE提高水泥糊的分散性和降低粘度的关键机制是由于扩散水层较薄,自由水的增加.
- 超分支PCE为提高水泥材料性能提供了一个有希望的替代方案,特别是在低W/C应用中.
- 定制聚合物架构对于优化超级可塑剂效率至关重要.
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