80电影天堂网,少妇高潮一区二区三区99,jαpαnesehd熟女熟妇伦,无码人妻精品一区二区蜜桃网站

相關鏈接
聯(lián)系方式
  • 通信地址:杭州市潮王路18號
  • 郵編:310014
  • 電話:0571-88320917
  • 傳真:
  • Email:wangjl@zjut.edu.cn
當前位置:> 首頁 > 論文著作 > 正文
The stability of covalently immobilization of TEMPO on the polymer surface through ionic liquid linkage: a comparative and model research.
作者:Danjie Li, Xianbo Shen, Liang Chen, Huanchang Jiang, Jianli Wang*.
關鍵字:alcohols, heterogeneous catalyst, ionic liquid, recyclability,stability
論文來源:期刊
發(fā)表時間:2015年
Covalently immobilizing the active sites or ligands on a polymer surface is an efficient strategy to achieve a full use of expensive organic parts. In this work, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) was anchored onto polystyrene beads through an ether bond or an ionic liquid bridge. We quantitatively compared their thermal stabilities at nitrogen atmosphere and their chemical stabilities in a biphasic oxidation surrounding. It was found that the ionic liquid-bridged TEMPO exhibited an additional advantage of stability and could be reused for 30 consecutive recycles with a conversion ratio above 90% without any significant loss under the condition of the Montanari oxidation system (NaClO/NaBr, CH2Cl2/water), and the overall reaction time exceeded 2700 min.