硬化自愈弹性体具有链式移动性的自愈弹性体
Matthew Wei Ming Tan1,2, Patrick Michael Thornton3, Gurunathan Thangavel1
1School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|June 13, 2024
概括
在软弹性体中调整聚合物链的移动性可以提高骨折性和自我愈合. 这提高了软件设备的耐用性和运行寿命,通过允许更好的损坏恢复.
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
背景情况:
- 软弹性体对于现代设备至关重要,但它们的使用寿命因易受损坏而受到限制.
- 提高骨折性和自我愈合能力对于提高这些材料的耐用性和寿命至关重要.
研究的目的:
- 调查方法,以提高骨折性和自我愈合在碳氧化功能化聚氨.
- 了解聚合物链流动性在实现这些改进材料性能方面的作用.
主要方法:
- 加入增塑剂和热处理来调整聚合物链的流动性.
- 断裂性测试,包括双悬臂梁测试,以评估材料性能.
- 不同的温度 (80-120°C) 和增塑剂度 (最优的是3 wt.%) 来评估性能增强.
主要成果:
- 温度从80°C上升到120°C显著提高了骨折的恢复工作 (2.86到123.7MJ m-3).
- 在最佳的塑化剂 (3重量%) 和温度 (40°C) 条件下,破裂性分别从16.3提高到19.9和25.6kJ m-2.
- 碳酸键和链的移动性被确定为能量消散和应力再分配的关键机制,导致裂变.
结论:
- 调整聚合物链流动性是一种有效的策略,可以同时提高柔软弹性体的断裂性和自我愈合.
- 这些改进有助于防止损坏,并促进更好的恢复,延长软设备的功能寿命.
- 了解治愈接口的断裂力学对于预测材料行为和自我治愈弹性体的故障预防至关重要.
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