Optical and Microstructural Changes in 5(6)-Carboxyfluorescein Doped PVA

Abstract

Abstract

The effect of 5(6) Carboxyfluorescein dye on microstructural and optical properties of a Poly(vinyl alcohol) (PVA) have been studied by using FTIR and UV-Visible absorption techniques. FTIR spectral result shows the possible interaction between the dye and PVA. The UV-Visible spectra shows three absorption bands (around 227nm, 310nm and 450nm) and from the observed optical band edges in the UV-Visible spectra, three optical band gaps and three activation energies for the doped PVA were estimated. The variation of optical band gap and activation energies with different dopant concentration indicates the existence of additional levels in the doped samples which reflects the modification in the microstructure of the polymer composite. Fluorescence emission band around 515nm was observed for 493nm excitation. These results are discussed based on charge transfer complex (CTC) formation. Increase in decay time of dye doped PVA matrix increases with the increasing concentration of 5(6) CF was observed.

Keywords: Dye, PVA, optical parameters, microstructure and lifetime decay

Cite this Article

Renuka Sali, Naik LR, Mohan S. Optical and Microstructural Changes in 5(6)-Carboxyfluorescein Doped PVA. Journal of Polymer & Composites. 2016; 4(3): 45–51p