偏好的形成的立体复杂晶体在多 (L-乳酸) /多 (D-乳酸) 混合由一个富勒烯核子核子
Wei-Wei Chang1, Jinye Niu1, Hui Peng1
1Analysis and Testing Center, Shandong University of Technology, Zibo, Shandong 255049, China.
International journal of biological macromolecules
|October 5, 2023
概括
将C70富勒烯添加到多 (L-乳酸) /多 (D-乳酸) 混合物中,可以促进立体复合体结晶. 这种方法增强了热稳定性,并抑制了高分子量聚酸材料的不必要的同晶化.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 结晶科学 结晶科学
背景情况:
- 立体复合体 (sc) 结晶在等离子多分子 (L-乳酸) /多分子 (D-乳酸) (PLLA/PDLA) 混合物中是改善聚酸 (PLA) 特性的关键.
- 同型结晶 (hc) 通常在高分子量 (HMW) PLLA/PDLA中占主导地位,阻碍了sc的形成.
- 在HMW PLLA/PDLA中开发有利于sc结晶的方法对于先进的材料应用至关重要.
研究的目的:
- 为了研究C70富勒作为核子对HMW PLLA/PDLA混合物中sc结晶的作用.
- 为了抑制HC结晶并促进SC形成,使用C70.
- 通过受控结晶来增强PLLA/PDLA混合物的热性能.
主要方法:
- 非异热结晶研究.
- 广角X射线衍射 (WAXD) 分析.
- 同热结晶实验. 同热结晶实验.
- 富里埃转换红外光谱学 (FTIR).
主要成果:
- 1重%C70压倒性诱导了sc结晶体的形成,同时防止HMW PLLA/PDLA中的hc结晶体.
- C70显著减少了140°C的半结晶期.
- FTIR表示C70增强了分子间相互作用,限制了链的移动性,加速了SC的形成.
- 使用1重%C70的PLLA/PDLA混合物表现出15.5°C更高的热稳定性.
结论:
- 在HMW PLLA/PDLA混合物中,C70作为选择性结晶的有效核子.
- 添加C70抑制了HC结晶,加速了SC的形成.
- 通过C70添加增强sc结晶导致PLA材料的热稳定性得到显著改善.
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