将两极化拉曼光谱和双折射作为3D打印热塑性塑料中分子尺度对齐的探针进行比较
Nora M Hassan1, Kalman B Migler2, Angela R Hight Walker3
1Hopkins Extreme Materials Institute, Johns Hopkins University, Baltimore, MD, USA; Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA; Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA.
MRS communications
|March 14, 2024
概括
了解3D打印中的聚合物链方向是关键. 极化拉曼光谱和双折度测量显示,拉曼比双折度更准确地量化聚合物链对齐在聚碳酸丝.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 增材制造 增材制造 增材制造
背景情况:
- 聚合物链的方向在热塑性挤出添加剂制造中显著影响材料特性.
- 挤出过程中的流场和快速冷却可以诱导链条的拉伸和对齐,影响间扩散和结晶.
- 极化拉曼光谱为量化聚合物链方向提供了一种非破坏性的,对表面敏感的技术.
研究的目的:
- 在3D打印的聚碳酸纤维中研究和量化聚合物链的方向和对齐.
- 为了比较两极化拉曼光谱和双断度测量的有效性,以评估链条方向.
- 为了开发拉曼光谱和双折度之间的相关性,以估计聚合物链的方向.
主要方法:
- 在3D打印的聚碳酸纤维上利用极化拉曼光谱和双折度 (Δn) 测量.
- 采用主要组件分析 (PCA) 来区分取决于方向和独立的振动模式.
- 应用了局部最小平方 (PLS) 回归来将拉曼测量与双折度相关并估计方向度.
主要成果:
- 使用PCA和PLS回归开发了两极化拉曼光谱和双断度测量之间的相关性.
- 发现与拉曼光谱相比,测量的双折值往往低估了聚合物链定向的程度.
- 在各种拉力比率处理的聚碳酸丝中量化链条方向.
结论:
- 极化拉曼光谱为3D打印材料中的聚合物链方向量化提供了一种比双折射更准确的方法.
- 开发的相关性使得从拉曼测量中估计双折射,有助于描述聚合物动态.
- 精确量化链路方向对于优化增材制造工艺和材料性能至关重要.
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