探索分子结构对治疗动力学的影响:对双甲和F环氧树脂的滴甘乙烯进行比较研究
Atsuomi Shundo1, Nguyen Thao Phan2, Mika Aoki3
1Department of Applied Chemistry, Kyushu University, Fukuoka 819-0395, Japan.
The journal of physical chemistry. B
|May 3, 2024
概括
环氧树脂中的甲基组 (双A和F的二甲基乙烯) 影响固化动力学. 尽管具有相似的环氧基反应性,但双F的二甲基乙醇由于分子间堆叠而表现出较慢的初始固化.
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
- 有机化学 有机化学
背景情况:
- 环氧树脂是重要的聚合物,其特性取决于其固化过程.
- 固化反应涉及环氧和氨基化合物,形成一个交联网络.
- 基于双A (BPA) 和双F (BPF) 的环氧树脂被广泛使用.
研究的目的:
- 为了研究甲基对环氧树脂固化动力学的影响.
- 为了比较双甲基 (4,4'-DGEBA) 的二甲基乙烯和双乙烯 (4,4'-DGEBF) 的二甲基乙烯的固化行为.
- 阐明导致固化速率差异的潜在机制.
主要方法:
- 里埃变换红外光谱 (FT-IR) 用于监测化学反应.
- 不同扫描热度计 (DSC) 分析固化热力学和动力学.
- 紫外 (UV) 光谱,广角X射线散射 (WAXS),密度函数理论 (DFT) 和分子动力学 (MD) 模拟来研究分子相互作用.
主要成果:
- 在4,4'-DGEBA和4,4'-DGEBF之间的环氧基的内在反应性没有显著差异.
- 当使用相同的氨基酸固化时,4,4'-DGEBF的初始固化反应速度比4,4'-DGEBA慢.
- 4,4'-DGEBF的分子间堆叠被确定为延迟固化的原因.
结论:
- 甲基组的存在导致了4,4'-DGEBF中的分子间堆叠,阻碍了反应分子的扩散和接近.
- 这种分子排列显著影响了环氧树脂的初始固化动力学.
- 了解这些结构效应对于为特定应用量身定制环氧树脂特性至关重要.
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