热力学特性和相隔形态的热混合环氧青粘合剂与不同的环氧树脂度的相隔形态
Chengwei Wu1, Haocheng Yang1, Xinpeng Cui1
1MOE Key Laboratory of High Performance Polymer Materials and Technology, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Molecules (Basel, Switzerland)
|July 27, 2024
概括
本研究探讨了环氧树脂 (ER) 度如何影响热混合环氧青结合剂 (WEABs). 较高的ER度会影响粘度,热力学性能和相隔,影响粘合剂性能.
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:
- 环氧青粘合剂 (EAB) 在道路建设中至关重要.
- 它们的性能与环氧树脂 (ER) 和含量有关.
- 了解相位分离是优化EAB属性的关键.
研究的目的:
- 研究不同氧树脂 (ER) 度 (10-90%) 对热混合氧青结合剂 (WEAB) 的影响.
- 分析粘度的变化,热力学特性和相隔形态.
- 为了将这些变化与粘合剂性能特征相关联.
主要方法:
- 布鲁克菲尔德旋转粘度计测量粘度随时间的推移.
- 不同扫描热度计 (DSC) 和动态机械分析 (DMA) 用于热力学性能.
- 激光扫描共聚焦显微镜 (LSCM) 用于可视化相隔微观结构.
主要成果:
- 随着ER度的变化,WEAB的粘度行为发生了变化,呈现出不同的阶段.
- 具有10-80%ER的WEAB显示两种玻璃过渡温度 (Tg);90%的ER显示一个Tg.
- 阶段逆转发生在50-90%的ER,从持续青到持续环氧相的过渡.
- 拉力强度在相位逆转后急剧增加;性在70%ER时达到顶峰.
结论:
- 环氧树脂度在很大程度上决定了WEABs的风湿学,热学和形态学特征.
- 阶段逆转是一种影响机械性能的关键现象,例如抗拉强度和性.
- 优化ER度对于为特定应用量身定制WEAB性能至关重要.
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