使用基于 (III) 的催化剂系统完美交替的CO2和化的共聚
Guang-Peng Wu1, Sheng-Hsuan Wei, Wei-Min Ren
1State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, People's Republic of China.
Journal of the American Chemical Society
|August 23, 2011
概括
这项研究证明了使用新型催化剂从二氧化碳和化中有效合成可生物降解的聚碳酸盐. 该研究强调了选择性共聚合与缺电子环氧化物所面临的挑战.
科学领域:
- 聚合物化学 聚合物化学
- 绿色化学 绿色化学
- 催化剂是一种催化剂.
背景情况:
- 通过与环氧化物共聚合利用二氧化碳,可以产生可生物降解的聚碳酸盐.
- 之前的研究主要使用阿里法性环氧化物,对带有电子吸收组的环氧化物 (如化水素) 取得的成功有限.
- 开发高效的催化剂,以各种环氧化物共聚化二氧化碳,对于可持续的化学合成至关重要.
研究的目的:
- 报告使用epichlorohydrin和CO2的二氧化碳共聚物的选择性合成.
- 为了研究循环碳酸盐和聚碳酸盐形成之间的动力差异,用于化和氧化物.
- 使用先进的分析技术阐明CO2/epichlorohydrin共聚合的机制.
主要方法:
- 使用二元和双功能 (盐) (III) 催化剂的二氧化碳和化的交替共聚化.
- 现场红外光谱学用于对循环碳酸盐与共聚合物形成的比较动力学研究.
- 电子喷射电离质谱仪 (ESI-MS) 用于直接观察聚合物链物种.
主要成果:
- 制造具有99%以上碳酸链接的二氧化碳共聚合物,由化水素制成.
- 动力分析显示,与氧化物 (53.5 kJ / mol) 相比,与氧化物 (45.4 kJ / mol) 共聚的激活能差异较小,这表明选择性共聚合物合成的难度更大.
- ESI-MS证实了由此产生的共聚合物的完美交替结构,并建议了涉及MTBD的潜在中间体.
结论:
- 该研究成功地从二氧化碳和化中产生高纯度的聚碳酸盐,显示了二氧化碳利用的显著进步.
- 动态洞察力解释了选择性共聚合与缺电子环氧化物的挑战.
- 这些发现为开发基于二氧化碳的聚合物合成更有效的催化剂提供了机制基础.
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