关于低等级硬青的衰老机制和高温风湿学特性研究
Liang Song1,2,3, Xiaodong Xie4,5, Pengcheng Tu5
1Xinjiang Transportation Investment (Group) Co., Ltd., Urumqi 830006, China.
Materials (Basel, Switzerland)
|August 26, 2023
概括
低级硬青具有更好的耐老化和高温性能,使其适用于具有挑战性的环境. 这项研究分析了青在各种条件下的老化,揭示了关键性能指标.
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:
- 在高温和高海拔地区的青性能对于基础设施的耐用性至关重要.
- 了解在热氧化和紫外线压力组合下的青老化机制是必不可少的.
研究的目的:
- 在老化条件下评估低级硬青 (30#,50#,70#) 的性能和高温湿学特性.
- 调查这些青对于高温和高海拔应用的适用性.
主要方法:
- 分析青的基本特性,里埃变换红外光谱法 (FTIR),原子力显微镜 (AFM),凝透色谱法 (GPC).
- 进行了动态剪切风湿学 (DSR) 和多压力爬行恢复 (MSCR) 测试.
- 青样本经过热氧化老化 (RTFOT,PAV) 和紫外线 (UV) 老化.
主要成果:
- 随着老化时间的增加,青的性能下降;塑性因热氧和紫外线老化而显著降低.
- 碳和硫氧化物指数在衰老后增加,表明化学结构发生了变化.
- 30#青在长时间的紫外线照射下,与50#和70#相比,具有更高的耐老性. 高温的风湿性质排名为30#>50#>70#.
结论:
- 低质量的硬青具有优越的抗衰老能力和高温风湿性质.
- 这些发现支持低质量的青在苛刻的环境条件下的潜在应用.
- 老化显著改变了青的组成,将更轻的成分转化为更重的部分,如树脂和青.
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