Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (5): 989-997.doi: 10.3866/PKU.WHXB201503252

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

Synthesis and Properties of Naphthalimide Fluorescent Dye and Covalent Fluorescent Polyurethane Emulsion

JIN Qing-Jun1, XU Min1, HUANG Xin-Yi1, LI Bo-Tian2, WANG Ji-Shuai1, KAN Cheng-You1   

  1. 1 Key Laboratory of Advanced Materials of Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China;
    2 PetroChina Petrochemical Research Institute, Beijing 100195, P. R. China
  • Received:2014-12-23 Revised:2015-03-25 Published:2015-05-08
  • Contact: KAN Cheng-You
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2014CB932202).


The reactive fluorescent dye 4- methoxy-N-(2- hydroxy- 1- hydroxymethylethyl) naphthalimide (MHHNA) was first synthesized by imidization and substitution reactions using 4-bromo-1,8-naphthalic anhydride, 2- amino- 1,3- propanediol, and sodium methoxide as initial materials. A series of covalent fluorescent polyurethane (PU) (PU-MHHNA) emulsions were then fabricated using MHHNA as the chain extender through a phase inverse self-emulsification process. The chemical structure of the synthesized fluorescent dyes and the properties of PU-MHHNA emulsions and their latex films were characterized by 1H nuclear magnetic resonance (1H NMR) spectroscopy, 13C nuclear magnetic resonance (13C NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, elemental analysis, ultraviolet- visible (UV- Vis) absorption spectroscopy, fluorescent spectroscopy, particle size analysis, and xenon arc aging measurements. The fluorescent quantum yields of MHHNA and PU-MHHNA were 0.73 and 0.92, respectively. The amount of MHHNA had no obvious influence on the colloidal properties of the PU-MHHNA emulsions. The maximum wavelength (λmax) of the UVVis absorption spectra was 360.6 nm, and fluorescent spectroscopy analysis indicated that the maximum excitation wavelength (λex) and maximum emission wavelength (λem) of PU-MHHNA in acetone were 362 and 435 nm, respectively. In addition, the fluorescence intensity of PU- MHHNA decreased with increasing temperature. The light fastness and solvent fastness of the PU-MHHNA film were much better than those of the non-covalent fluorescent polyurethane (PU/MBNA) film.

Key words: Fluorescent dye, Polyurethane, Absorbance, Fluorescence intensity, Light fastness