Preparation of Composite Polymethylmethacrylate /Silver (PMMA/Ag) Films and Studying the Effect of Silver Nanoparticles on their Optical Properties

Abstract

 In this work to a realization the effect of nanoparticle of Silver on the optical properties of Polymethylmethacrylate (PMMA) films prepared by using casting technique at a temperature (50?C) with thickness (8±1?m). The optical properties of the composite were done by measuring the  absorption and transmission spectra  as a function of wavelength (200-800) nm. The results of measurement showed that the transmittance of the films decreased with increasing the addition of silver nanoparticle due to increasing of attenuation of incident light with a clear increase of absorption and a decrease in optical reflectivity. As well as calculated the optical constants (?,k, and ?r) of the prepared films and the results showed an increase when increasing addition.The real part (?r) of the dielectric constant behave like the refractive index, while the imaginary part (?i) of the dielectric constant behave like the extinction coefficient, as for optical conductivity its values increases as increasing the rate of the Nano silver , and the identifying of the types of electronic transitions and determining energy gaps. It was found there is diminution in energy gap for direct electron transmission reaching values (5.4 - 4.9)  eV.