在具有化学相同物种的纠聚合物溶液中,广泛的流动诱导度梯度
Shuang Liu1,2, Li Peng2, Siying Xiang3
1Polymer Research Institute, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
ACS macro letters
|January 11, 2024
概括
快速延伸流导致聚合物溶液中的度梯度,这与经典的管模型相矛盾. 这项研究使用光探针可视化了这些梯度,揭示了影响风湿学的微域.
科学领域:
- 聚合物物理 聚合物物理
- 类风病学 类风病学 类风病学
- 材料科学 材料科学 材料科学
背景情况:
- 与在快速延伸流下化的聚合物相比,纠的聚合物溶液表现出明显的质行为.
- 这种差异挑战了经典管模型的预测,突出了聚合物物理学中一个尚未解决的问题.
- 经典的管道模型假定聚合物度均,在动态流量条件下可能不成立.
研究的目的:
- 为了研究聚合物溶液中扩展性流量诱导的度梯度的发生.
- 在快速延伸流中调和聚合物溶液和化物之间观察到的质差异.
- 在特定流量条件下挑战经典管模型的同质性假设.
主要方法:
- 使用聚合诱导排放 (AIE) 探针标记在寡合溶剂上以可视化度变化.
- 结合学测量与现场光显微镜,观察流动诱导的现象.
- 在延伸流下分析溶剂微域的形成和特征.
主要成果:
- 延伸流会导致聚合物溶液中的度梯度,即使化学成分相同.
- 视觉化揭示了小聚合物溶剂的微域,其特征是长度尺度为几十微米.
- 这些观察到的微域显著影响了聚合物溶液的整体质行为.
结论:
- 经典的管道模型需要改进,以考虑聚合物溶液中流量诱导的度异质性.
- 在延伸流下溶剂微域的形成是影响聚合物溶液质学的关键因素.
- 这项研究为了解非平衡流条件下的聚合物动力学提供了新的视角.
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