拉曼结构分析L-乳/ε-烯酸盐共聚合物和多L-乳/多ε-烯酸盐混合物
S O Liubimovskii1, V S Novikov1, E V Anokhin2
1Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russian Federation.
概括
这项研究介绍了拉曼光谱法,用于分析多聚L-乳酸/多聚ε-烯酸 (PLCL) 共聚物. 这些技术可以准确地确定LLA/CL混合物的共聚合物组成和结晶性.
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L-乳酸/聚ε-烯酸 (PLCL) 共聚合物是重要的生物降解材料.
- 描述它们的组成和结晶性对于理解它们的特性至关重要.
- 现有的PLCL分析方法在范围和准确性方面存在局限性.
研究的目的:
- 开发和验证基于拉曼光谱的方法来分析PLCL共聚合物.
- 扩大现有的分析技术,覆盖更广泛的共聚合物组合物.
- 为评估PLCL共聚合物特性提供一个全面的方法.
主要方法:
- 通过散环开放聚合物合成PLCL共聚合物的合成.
- 对共聚合物样本进行拉曼光谱分析.
- 广角X射线散射 (WAXS) 用于结晶度的确定.
- 对特定拉曼峰强度比率的定量分析.
主要成果:
- 扩展了用PLLA波段 (411/874厘米−1) 测定多L-乳酸 (PLLA) 块结晶度的方法,以达到50mol%的e-caprolactone (CL) 含量.
- 引入了一种新方法,使用聚乙烯 (PCL) 带 (958/1110 cm−1) 来评估PCL块结晶性.
- 通过使用PLLA/PCL波段 (2947/2914厘米−1) 验证了一种方法,用于确定整个CL范围和PLLA/PCL混合物中的相对共同分子含量.
结论:
- 拉曼光谱为表征PLCL共聚合物提供了一种通用且准确的工具.
- 开发的方法允许精确量化共聚合物组成和块结晶性.
- 这些进步促进了PLCL材料的定制设计和应用.
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