改性青的拉伸性质和纳米级阶段结构及其老化行为的表征
Yuhui Zhang1, Ming Wang1, Chengwei Xing2
1School of Traffic Science and Engineering, Civil Aviation University of China, Tianjin 300300, China.
Polymers
|November 27, 2024
概括
这项研究研究了改性青,发现SBS&CR和SBS&TiO2复合材料具有优越的拉伸性能和耐老性. TiO2提高了相结构稳定性,而CR显示了相结构上显著的老化效应.
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.
- 聚合物科学 聚合物科学
背景情况:
- 青改造对于提高路面性能和耐用性至关重要.
- 了解改性青的纳米尺度行为和老化机制对于材料设计至关重要.
- styrene-butadiene-styrene (SBS),碎 (CR) 和二氧化 (TiO2) 是常见的修饰剂,具有不同的效果.
研究的目的:
- 探索不同改性青的拉伸性能和纳米级相位结构.
- 在短期和长期老化条件下研究这些改性青的老化行为.
- 为了将纳米级相位结构与宏观性能和抗衰老性相关联.
主要方法:
- 准备原始青,SBS改性青,SBS和CR复合青,以及SBS和TiO2复合青.
- 强力柔性测试,以评估拉伸性能.
- 原子力显微镜 (AFM) 用于分析纳米级相结构.
- 短期衰老 (STA) 和长期衰老 (LTA) 的实验.
主要成果:
- 这三种修改后的青都表现出柔性骨折.
- 与SBS青相比,SBS&CR和SBS&TiO2青表现出优越的拉伸性能和耐老性.
- TiO2的修饰导致了更稳定的相位结构,具有统一的"蜜蜂"相位,并且在老化过程中抑制了极性分子聚合.
- 由于颗粒和青之间的相互作用,SBS&CR青在老化时显示出更显著的相位结构变化.
结论:
- SBS&CR和SBS&TiO2复合青提供了增强的拉伸性能和耐老化性能.
- 二氧化作为稳定剂,改善了青阶段结构和耐老化的性能.
- 复合材料和青之间的相互作用会影响复合材料的老化行为,从而导致更明显的结构变化.
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