作为水泥添加剂的聚乙烯:添加方法对化动力学的影响
Sara Beldarrain1, Guido Goracci2, Jorge S Dolado2
1POLYMAT, Kimika Aplikatua Saila, Kimika Fakultatea, University of the Basque Country, UPV/EHU, Joxe Mari Korta Zentroa, Tolosa Hiribidea 72, 20018 Donostia-San Sebastián, Spain.
Materials (Basel, Switzerland)
|November 9, 2024
概括
聚碳酸乙烯 (PCE) 超塑性剂根据添加方法对水泥水化有不同的影响. 直接添加延缓了水合,而延迟添加则减少了没有延迟的速度,与PCE微观结构有关.
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.
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚碳酸乙烯 (PCE) 是水泥配方中至关重要的超塑性剂.
- 最近的研究探讨了PCE分子结构和性能之间的联系.
- 了解PCE对水泥水化的影响对于材料优化至关重要.
研究的目的:
- 为了研究不同侧链长度和电荷密度的PCEs对普通波特兰水泥 (OPC) 水化的影响.
- 为了确定不同的PCE添加方法如何影响水泥水化动力学.
- 为了将PCE微观结构与观察到的水合效应相关联.
主要方法:
- 通过自由基共聚合,合成具有受控侧链长度和电荷密度的PCE.
- 使用直接和延迟方法 (5分钟后添加水) 将合成的PCE添加到OPC糊中.
- 对水泥水化动力学和微观结构的分析.
主要成果:
- 添加PCE的方法显著改变了OPC水化动力学.
- 直接添加PCE显示了水解延迟和PCE微观结构之间的线性关系.
- 延迟PCE添加会降低水合率,但不会导致延迟,不管PCE的微观结构如何.
结论:
- 添加PCE的方法是控制水泥水化的一个关键因素.
- 直接添加提供了一种根据PCE分子设计量身定制水化阻滞的方法.
- 延迟添加提供了一种方法,可以在没有显著延迟的情况下适度降低水合率,从而在混凝土技术中提供灵活性.
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