多聚的隐藏的异态结晶 ((ε-Caprolactone-Ran-ω-Pentadecalactone) 的共聚物
Juan Torres-Rodríguez1, Ricardo A Pérez-Camargo1, Yunxiang Shi1
1POLYMAT and Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, Faculty of Chemistry, University of the Basque Country UPV/EHU, Paseo Manuel de Lardizabal, 3, Donostia-San Sebastián 20018, Spain.
Biomacromolecules
|May 15, 2025
概括
聚 ((ε-caprolactone-ran-ω-pentadecalactone) kopo 聚合物是异态的,结晶的条件是独立的. 这挑战了关于它们晶体行为和结构的先前假设.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 聚乙烯 (PCL) 和聚乙烯 (PPDL) 是可生物降解的聚合物.
- 了解共聚合物结晶对于材料性能和应用至关重要.
- 以前的研究表明,PCL-PPDL共聚物可能是异构的.
研究的目的:
- 合成不同成分的PCL-PPDL共聚物.
- 调查它们的结晶行为,并确定它们是异态的还是异态的.
- 在不同的结晶条件下澄清共纳物质的包含/排除平衡.
主要方法:
- 使用Candida antarctica lipase B.进行环开放聚合.
- 不同扫描热量计 (DSC).差异扫描热量计.
- 极化光光学显微镜 (PLOM). 极化光光学显微镜.
- 在现场广角X射线散射 (WAXS) 和小角X射线散射 (SAXS).
- 里埃变换红外光谱法 (FTIR). 福利埃变换红外光谱法.
- 自核化试验. 自核化试验.
主要成果:
- 聚合物在所有组合中都表现出伪学行为.
- 结晶发生在PPDL型或PCL型单元细胞和形状中,无论条件如何.
- 自核化数据表明,域II宽度随着comonomer含量增加而下降.
- 在PCL含量超过83%时,识别出了一个伪学术点.
结论:
- PCL-PPDL共聚物是异态的,而不是之前报道的异态.
- 在各种组成和结晶条件中保持异态性质.
- 已识别的伪修学点解释了以前未被识别的异态形状的特征.
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