Journal of South China University of Technology (Natural Science Edition) ›› 2006, Vol. 34 ›› Issue (8): 75-78.

• Chemistry & Chemical Engineering • Previous Articles     Next Articles

Influence of Solventa Properties on Fluorescent Properties of Water-Soluble Cellulose Ethers/Eu(Ⅲ)

Ye Jun1  Xiong Jian2   

  1. 1·State Key laboratory of Pulp and Paper Engineering,South China Univ.of Tech.,Guangzhou 5 10640, Guangdong,China;2·School of Light Industry and Food Sciences, South China Univ.of Tech.,Guangzhou 5 10640, Guangdong,China
  • Received:2006-03-06 Online:2006-08-25 Published:2006-08-25
  • Contact: 叶君(1963-)，女，博士，副教授，主要从事纤维素及其他天然大分子的化学改性和功能化应用的研究 E-mail:jye@scut.edu.cn
  • About author:叶君(1963-)，女，博士，副教授，主要从事纤维素及其他天然大分子的化学改性和功能化应用的研究
  • Supported by:

    国家自然科学基金资助项目(50573025，20436020)

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Abstract:

The effects of solvent polarity and protonic solvent on the fluorescent properties of hydroxyethvl cellulose (HEC)/Eu(Ⅲ)，methyl cellulose(MC)/Eu(Ⅲ)and carboxymethyl cellulose(CMC)/Eu(m)complexes were investigated by fluorescent spectroscopy to reveal the interaction between the fluorescent substance and the solvent on the microcosmic level.The results show that(1)the dipole moment of HEC/Eu(Ⅲ)complex in the excited state greatly changes with the increase in the polarity of H2O/CH3OH solvent,which makes the fluorescent spec.trum of HEC.Eu(Ⅲ)complex,whose intensity depends on various factors,shifts to the long-wavelength side:(2) the Increase in the H2 concentration of H2O/HAc solvent results in a reorientation of the solvent cag es around MC/Eu(Ⅲ)complex as well as a great Stokes shift of the fluorescent spectrum due to the solvent relaxation:and(3)
the increase in the polarity of H2O/CH3COCH3 solvent has no obvious efect on the Stokes shilt of CMC/Eu (Ⅲ)complex,but it may break the equilibrium between intra-and inter.molecular hydrogen bonds in the complexes.thus changing the structure of the fluorescent substance and the intensities of the fluorescent spectra

Key words: solvent property, Stokes shift, water-soluble cellulose ethers/Eu(Ⅲ), fluorescent propeny