通过显式溶剂模型对纤维素和环氧化物之间的同质催化交联行为进行机械洞察
Zhifeng Yan1, Youbo Di2, Le Wang2
1College of Textile Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China; College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China; National Advanced Functional Fiber Innovation Center, Suzhou 215228, Jiangsu, China.
International journal of biological macromolecules
|August 13, 2023
概括
均质催化剂影响纤维素与环氧化物交叉连接. 易斯酸提供了活性和区域选择性的平衡,而像NaOH这样的强基显示了最高的催化效率.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 聚合物化学 聚合物化学
背景情况:
- 纤维素材料的功能性改造是一个不断增长的研究领域.
- 了解交联反应是开发基于纤维素的新材料的关键.
- 同质催化提供了对化学反应的可调控控制.
研究的目的:
- 使用各种同质催化剂,系统地研究纤维素与环氧化物的交联.
- 阐明催化剂类型,电子效应和固体阻碍对反应结果的影响.
- 为了比较不同类型的催化剂中的催化活性和区域选择性.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 使用混合微溶解连续的方法来建模反应环境.
- 分析了H2O,布伦斯特德酸,布伦斯特德基,易斯酸和中性盐的催化行为.
主要成果:
- 所有研究的同质催化剂都在纤维素-环氧化物交联反应中表现出活性.
- 催化活性按照以下顺序进行:NaOH > HCl > NCl3 > MCl2 > CH3COOH > NaCl.
- NaOH通过carbanion中间体表现出极好的区域选择性,而易斯酸则在活性和区域选择性之间提供了平衡.
结论:
- 催化剂类型,电子效应和固体阻碍共同决定反应结果.
- 易斯酸由于其平衡的性能,为纤维素交叉连接提供了一个有希望的催化策略.
- 这些发现提供了通过受控交联反应优化纤维素功能化的见解.
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