Structural and optical properties of new poly vinyl alcohol grafted methyl red (PVA-G-MR)‎

Abstract EN

New polymeric dye films have been synthesised by condensation polymerization and reaction polyvinyl alcohol with methyl red dye to produce a new graft copolymer (PVA-g-MR) .The structural properties of these samples were investigation by FTIR and XRD .The FTIR spectra indicated the important functional groups for polymer and dye ,The peak at 1708cm-1 related to carbonyl groups indicated the correct reaction between PVA and dye.

XRD investigation indicated the crystalline structure to new polymer .Optical parameters have been studied by preparing thin films on glass substrates using cast technique.

Many optical parameters have been calculated depending on absorption and reflective spectra in the wavelength range (300-1000)nm , such as refraction index n(1.58) , absorption coefficient α , optical energy gap Eg (2.05eV), dielectric constant (2.52), Urbach tail (186meV) and real and imaginary part of dielectric constant , Surface energy(SELF) and volume energy loss(VELF) were also investigated by depending on real and imaginary parts of dielectric constant .It is clear that the value of VELF greater than the peak of SELF ,it is also clear that of SELF and VELF around energy region 2.35eV and 2.5eV respectively.

Optical ,electrical conductivities (σopt , σe ) were also investigate , σopt increasing by increased the photon energy related to strong absorption .The results satisfied Wimple –Dideminco formula .Optical parameters of (PVA-g-MR) are useful to make the materials a prominent one for solar cell applications.