机械研究HF/BF3-催化炭聚合物,以准备中相位
Xi Fan1, Qiang Ren2, Haiping Shen2
1Research Institute of Petroleum Processing, SINOPEC, Beijing, 10083, China. fanxi_fanxi@163.com.
Journal of molecular modeling
|January 6, 2024
概括
这项研究使用了分子模拟来研究酸/三化 (HF/BF3) 催化的人青素反应. 研究结果揭示了影响美索相间距形成的碳化机制,影响了聚合物结构和特性.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 对于先进材料至关重要的中相,通常是通过酸催化制备的.
- 酸催化方法可以产生具有理想的低软化点和高溶解度的.
- 了解反应机制是控制美索相距微观结构的关键.
研究的目的:
- 阐明酸/三化物 (HF/BF3) 催化炭反应的机制.
- 为了研究碳酸盐在中相位形成中的作用.
- 为了将反应路径与产生的聚合物微观结构相关联.
主要方法:
- 使用材料工作室 (MS) 2020 采用分子模拟技术.
- 密度函数理论 (DFT) 与B3LYP函数和DNP基础集被用于计算.
- 应用分散校正 (DFT-D) 和过渡状态搜索 (LST/QST) 来分析反应路径和能量障碍.
主要成果:
- 两种类型的碳酸,古典和非古典,被确定为关键中间体.
- 提出了五种反应类型:质子化,链延长,分子内循环,脱质和脱.
- 链条延长以形成烯四度体呈现出比二度和三度体形成更高的能量障碍,而循环化增强了分子刚性和平坦性.
结论:
- 经典的carbocations促进链延长和循环,影响聚合物链的生长和结构.
- 非经典的碳酸可能参与脱反应,这可能解释产品中高酸含量.
- 这项研究提供了通过催化剂选择和反应路径操纵控制中相位调度属性的见解.
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