纠网络抑制了聚碳酸在超高应变速率下的性恶化
Peng Dong1, Jian-Bin Tang1, Han Shang1
1College of Polymer Science and Engineering, State Key Laboratory of Advanced Polymer Materials, Sichuan University, Chengdu, P. R. China.
Macromolecular rapid communications
|December 23, 2025
概括
聚碳酸 (PC) 中的高分子链纠可以在高张力率下提高机械性能. 增加的纠密度抑制了能量吸收的恶化,增强了材料在极端变形下的弹性.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
背景情况:
- 聚碳酸 (PC) 在窗户玻璃等安全应用中至关重要.
- 了解超高拉伸率的PC机械行为对于材料设计至关重要.
研究的目的:
- 为了研究分子链纠对PC机械性能在超高拉变速率的影响.
- 为了阐明背后的机制,应变速率依赖的机械行为和能量消耗.
主要方法:
- 机械测试跨越广泛的应变速率范围 (0.01100s-1).
- 使用数字图像相关性 (DIC) 的实时观测.
- 动态机械分析 (DMA) 用于评估能量消耗特性.
主要成果:
- PC的性随着延展率增加到100s-1而增加,在那里性和性恶化.
- DIC显示了严重的压力度和应变局部化在100s-1.1时.
- 高纠密度抑制了这种恶化,增强了应变硬化,增加了能量消散 (β-放松区域的损失模量和tan δ).
结论:
- 分子链纠显著影响PC在极端变形下的机械性能.
- 定制纠网络可以抑制能量吸收的恶化,提高材料的弹性.
- 由于纠而增强的能量消耗是改善抗变形的关键.
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