新的高分支多拉克PCL的合成和形态特征
Aleksandra Zioło1,2, Beata Mossety-Leszczak2, Małgorzata Walczak2
1Doctoral School of the Rzeszów University of Technology, al. Powstańców Warszawy 12, 35-959 Rzeszow, Poland.
Molecules (Basel, Switzerland)
|March 13, 2024
概括
一种新方法通过使用高分支聚胺 (HPPA) 宏观发起器合成可生物降解的分支聚烯酸 (PCL). 这种无溶剂的工艺产生具有可调节性质的核心外PCL-HPPA聚合物.
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
- 有机合成 有机合成
背景情况:
- 可生物降解的聚合物,如聚烯 (PCL) 对于可持续材料至关重要.
- 为分支聚合物架构开发高效的合成方法是一个持续的挑战.
- 超分支聚合物由于其球状结构和众多末端组而具有独特的特性.
研究的目的:
- 开发一种简单高效的无溶剂方法,用于合成高分支聚氨酸 (PCL).
- 使用超分支聚胺 (HPPA) 作为创建PCL-HPPA核心外结构的宏观发起者.
- 描述合成的分支PCL聚合物的结构,组成和特性.
主要方法:
- 大量使用氧酸 (Sn(Oct) 催化剂的卡普罗拉克的环开聚合 (ROP).
- 使用超分支聚胺 (HPPA) 作为宏启动器来形成PCL-HPPA核心外结构.
- 使用H NMR进行表征,元素分析,共聚焦拉曼微光谱,飞行时间二次离子质谱,冷传输电子显微镜 (cryo-TEM),凝透色谱 (GPC),微分扫描热度计 (DSC) 和X射线衍射 (XRD).
主要成果:
- 成功合成了具有核心外架构的可生物降解,分支的PCL-HPPA聚合物.
- 1H NMR和元素分析证实了HPPA的高移植转换和共价纳入.
- 光谱和显微技术 (拉曼,ToF-SIMS,冷TEM) 验证了核心外结构.
- GPC表示聚合产品的微小部分,可能是由于转化.
- DSC和XRD表明,PCL-HPPA聚合物保持了类似于线性PCL的结晶性,但具有更小,更不规则的结晶体.
结论:
- 建立了一种简单高效的无溶剂方法来生产分支PCL-HPPA聚合物.
- 合成的PCL-HPPA表现出一个明确的核心外结构,具有可调节的分支.
- 分支架构影响晶体形成,但保留了整体聚合物晶体性,为新型材料应用提供了潜力.
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