Enhancement of Urbach Energy and Dispersion
Parameters of Polyvinyl Alcohol with Kaolin
Additive
Abstract
Polyvinyl alcohol films have been prepared with various additives of Kaolin by casting method at a thickness of 10 μm.
The impacts of Kaolin additive on some optical parameters has been studied by recording the transmittance spectra
UV-Visible spectrophotometer in the range 200-900 nm after studied the structure from X-ray diffraction and FTIR to
determine the crystallites and the activation groups. Urbach energy increased with the increases of Kaolin additive
leading to decrease bandgap from 4.08 eV of PVA film to 3.77 eV of 4% Kaolin additives.
Key Words: Polyvinyl Alcohol, Kaolin, XRD, Dispersion Parameters, Urbach Energy.