通过低频拉曼成像来可视化聚[(R) -3-基酸]/聚 (L-乳酸) 中的同热结晶和相分离
1Graduate School of Human Development and Environment, Kobe University, Tsurukabuto, Nada-Ku, Kobe 657-8501, Japan.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
|February 23, 2024
概括
拉曼成像可视化了聚基酸 (PHB) 和聚-L-乳酸 (PLLA) 混合物的分子相互作用. 低频拉曼光谱在PHB/PLLA中对跟踪相位分离和结晶更为敏感.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 聚[(R) -3-基酸] (PHB) 和聚L-乳酸 (PLLA) 是一种可生物降解的聚合物.
- 了解它们的可混合性和相位行为对于材料应用至关重要.
- 分子间相互作用,如键 (C=OCH3),影响混合物特性.
研究的目的:
- 想象PHB/PLLA混合物中相分离和结晶期间分子间相互作用的变化.
- 为了比较低频和高频拉曼光谱的灵敏度,用于监测这些过程.
- 确定最佳的光谱区域,以检测相位分离和结晶的开始.
主要方法:
- 使用拉曼成像来研究PHB/PLLA可混合混合物.
- 在异热结晶过程中获得并比较高频和低频拉曼光谱.
- 专注于与PHB结相关的特定低频带 (75 cm−1) 和C=O拉伸带 (1720 cm−1).
主要成果:
- 拉曼成像成功地可视化了C=OCH3相互作用在相位分离和结晶过程中的变化.
- 75厘米-1的低频带有效地跟踪了结的变化.
- 低频带的结果与高频 C=O 拉伸带在 1720 cm-1.1 的结果相关性很好.
结论:
- 低频拉曼光谱比高频光谱更敏感,用于检测PHB中相分离和结晶的开始.
- 拉曼成像为混合物进化过程中发生的分子层次过程提供了宝贵的见解.
- 这项研究强调了低频拉曼分析对于聚合物混合物表征的有用性.
更多相关视频
相关概念视频
01:21Polymer Classification: Crystallinity
2.9K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
2.9K
01:20Raman Spectroscopy: Overview
390
The underlying principle of Raman spectroscopy is based on the interaction between light and matter, specifically molecules' inelastic scattering of photons. When a monochromatic beam of light, typically from a laser source, interacts with a sample, most scattered light has the same frequency as the incident light. This is known as Rayleigh scattering.
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and...
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and...
390
01:26Polymer Classification: Stereospecificity
2.4K
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
2.4K