揭示甲基聚乙烯甘乙烯对聚碳酸超塑性剂的性能及其与混凝土相关的脱敏功能的影响
Yongqi Da1, Longgang Yu1, Tingshu He1
1College of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Materials (Basel, Switzerland)
|February 26, 2025
概括
新的聚碳酸乙烯-硬化阻碍 (PCE-st) 超级可塑剂,使用不同分子量的甲基聚乙烯甘乙烯 (MPEG) 合成,有效降低水的敏感性和控制高强度混凝土中的水分. 在MPEG分子量600.0的情况下观察到最佳性能.
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.
- 聚合物化学 聚合物化学
背景情况:
- 高强度混凝土生产面临的挑战包括水含量敏感性,水泥适应性问题和高水温度.
- 聚碳酸乙烯 (PCE) 是修改混凝土性能的关键添加剂,但它们的性能可以受到分子结构的影响.
研究的目的:
- 为了合成新型的PCE-st超级可塑剂,具有不同分子量的甲基聚乙烯糖乙烯 (MPEG).
- 研究这些PCE-st添加剂对水泥和混凝土性能的影响,重点关注水需求,流动性,水分和强度.
主要方法:
- 在MPEG和甲基酸 (MAA) 之间发生化反应,形成MPEG-MAA中间体.
- 自由基共聚合MPEG-MAA,乙烯基醇聚乙烯基醇 (EPEG) 和烯酸 (AA),合成三种类型的PCE-st.
- 分析水泥和混凝土的性能,包括流动性,水含量变化的敏感性,水化温度,定时间和压力强度.
主要成果:
- 具有MPEG分子量600的PCE-st证明了水含量变化灵敏度的最佳降低 (流动性增加62毫米).
- 将MPEG分子量从400增加到1200降低了水化温度 (43.8°C至39.5°C),并将设置时间延迟了大约30分钟.
- 使用PCE-st的混凝土压力强度与商用PCE-et0.0的压力强度相当.
结论:
- 在PCE-st中MPEG的分子量显著影响混凝土中的超级可塑剂性能.
- 与MPEG (MW 600) 合成的PCE-st可以更好地控制水的灵敏度和流动性.
- 这些新型PCE-st添加剂提供了与商业PCE相比的性能,同时在水化控制方面提供了潜在的好处.
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