用金胺O作荧光探针研究PVA-H_2O-DMSO体系的凝胶过程

<正> 它在可见光区发荧光,其荧光量子效率随环境的粘度不同有较明显的变化。这是由于其分子中的芳香基团与中心碳是单键连接,易于转动。当环境的粘度增加时,这种转动受到阻碍,因而分子吸收激发光能后,损失于这种转动的热能相对减少,荧光量子效率则相对

STUDY ON GELATION PROCESS OF PVA-H2O-DMSO SYSTEM BY FLUORESCENCE PROBE.AURAMINE O

Polyvinyl alcohol solution in water-dimethyl sulphoxide will automatically change into gel. Auramine O as a fluorescence probe was added into the system. A self-catalytical curve, from which a gelation rate was taken out, of the gelation process was obtained by measuring fluorescence spectra of Auramine O. The effects of various component ratios in system on the gelation rate were examined. Kinetics of gelation was also studied by this method. It is found that the mole fraction of DMSO in the mixture solvent affected the rate of gelation. When the mole fraction of DMSO is 0.25, the rate of gelation reached the maximum. This phenomenon may be interpreted from the view of hydrogen bond formation. It is concluded that fluorescence probe method is efficient and easy for study of gelation process.