化学学报 ›› 2008, Vol. 66 ›› Issue (5): 576-580. 上一篇    下一篇

研究论文

客体小分子在超分子有机凝胶体系中的扩散释放

冯桂龙,王宏,杨亚江   

  1. (华中科技大学化学与化工系 材料化学与服役失效湖北省重点实验室 武汉 430074)
  • 投稿日期:2007-06-28 修回日期:2007-08-21 发布日期:2008-03-14
  • 通讯作者: 杨亚江

Diffusion and Release of the Guest Molecules in Supramolecular Organogel

FENG Gui-Long ,WANG Hong ,YANG Ya-Jiang*   

  1. (Hubei Key Laboratory of Materials Chemistry & Service Failure, Department of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074)
  • Received:2007-06-28 Revised:2007-08-21 Published:2008-03-14
  • Contact: YANG Ya-Jiang

采用二(4-硬脂酰胺基苯基)甲烷(BSAPM)为凝胶剂制备了含有小分子水杨酸和若丹明B的1,1,2-三氯乙烷(TCE)超分子有机凝胶. 以超分子有机凝胶作为主体, 客体小分子水杨酸和若丹明B可轻微降低超分子有机凝胶的相转变温度(TGS). 用紫外-可见光度法研究了超分子凝胶中两种客体小分子在静态下的扩散释放. 结果表明其释放率随凝胶剂浓度的增加而降低. 客体小分子的体积大小对其释放有明显的影响, 分子体积较大的若丹明B的释放率低于分子体积较小的水杨酸. 另外, 若丹明B的扩散系数也低于水杨酸, 且随凝胶剂浓度的增加, 这种趋势更为明显. 两种客体分子的累积释放率与时间的平方根成良好的线性关系, 符合Higuchi方程, 属扩散控制的Fickian释放机理.

关键词: 超分子有机凝胶, 客体分子, 扩散

Bis(4-stearamidophenyl)methane (BSAPM) was used as a gelator for preparation of 1,1,2-trichloroethane (TCE) supramolecular organogels. The existence of salicylic acid and rhodamine B as the guest molecules led to the slight decrease of gel-sol phase transition temperatures (TGS) of the organogels. The diffusion and release of the guest molecules in the organogels were investigated by using UV-vis spectroscopy. The results indicated that release ratios of the guest molecules decreased with the increase of the gelator concentration. Wherein, the release ratios of rhodamine B were less than those of salicylic acid, which could be attributed to the larger molecular size of rhodamine B. In addition, the diffusion coefficients of rhodamine B were also less than those of salicylic acid. This trend was clearer with the increase of BSAPM concentration. The investigation indicated that the diffusion and release behavior of the guest molecules in the self-assembled organogel followed the Higuchi equation and diffusion-controlled mechanism of Fickian model.

Key words: supramolecular organogel, guest molecule, diffusion