追踪青粘合剂的自我愈合能力的衰老诱导的进化:微观结构和风病学分析
1School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Langmuir : the ACS journal of surfaces and colloids
|November 25, 2024
概括
这项研究介绍了一种新型的自我修复青,该青利用具有动态二硫化物键的聚合物. 紫外线老化通过改变聚合物结构和分布,对其自我愈合能力产生负面影响.
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:
- 青路面由于紫外线辐射和热氧化等环境因素而降解.
- 开发耐用,自我修复的材料对于延长路面的寿命和性能至关重要.
- 具有动态共价键的聚合物为青中的自我修复应用提供了潜力.
研究的目的:
- 开发一种高效,耐用的自我修复青,使用具有动态二硫化物键的聚合物.
- 研究热氧化和紫外线衰老对改性青的自我愈合特性的影响.
- 分析影响衰老后自我愈合能力的微观结构和学变化.
主要方法:
- 开发聚合物改性青 (PUS-MA) 和PUS/乙烯/布他乙烯块共聚合物改性青 (PUS/SBS-MA).
- 在热氧化和紫外线老化条件下使用非脱索热系统促进自我愈合的评估.
- 通过光显微镜,FTIR,GPC和DSR进行微结构和风湿学分析.
主要成果:
- 发现紫外线衰老对PUS的自我愈合促进效果是有害的.
- 衰老引起的变化改变了修饰剂的分布,化学结构和宏分子分解.
- 减少分子链的移动性和改变聚合物中的键与自我愈合能力的降低相关.
结论:
- 经PUS修改的青的自我修复能力受到老化条件,特别是紫外线暴露的显著影响.
- 在动态二硫化物键聚合物中,分子链的移动性和键是自我愈合性能的关键决定因素.
- 了解衰老的影响对于设计强大的自我愈合的青材料至关重要.
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