Synthesis of hydrophilic P(VDF-TrFE) chloride sensitive polymer films for fluorescence sensing

Hydrophilic lucigenine doped P(VDF-TrFE) based chloride sensitive films were prepared by three different methods. These include increased pore size and distribution, introduction of alumina nanoparticles and addition of amphiphilic copolymer. The properties of the films were characterized by scanning electron microscope (SEM), contact angle meter (CAM), fourier transform infrared absorption spectroscopy (FT-IR) and photoluminescence (PL) spectroscopy. The PL intensity of chloride sensitive films is chloride concentration-dependent and the evolution of the lucigenine related PL intensity as a function of the chloride concentration follows the Stern-Volmer equation. From all the results, addition of amphiphilic copolymer shows the best effect on the hydrophilic modification of the film as well as the chloride sensitivity, and one of the optimal linear calibration formula I-0/I=1+15.069[Cl-] (R-2=0.981) was obtained in the concentration range 0.02 M-0.10 M of a standard sodium chloride solution with a detection limit of 0.01M (S/N=3).