Optical properties of PVC composite modified during light exposure to give high absorption enhancement

Abstract

Modified poly(vinyl chloride) (PVC) films have been synthesized with a simple superficial deposition by using solvent tetrahydrofuran (THF). These modified films were prepared by a casting method over a glass substrate. Different types of the amino group with a suitable aromatic aldehyde as an organic compound, which were reacted to prepare different PVC composite films. These films have been analyzed by UV-Visible spectra. The percentage of PVC was (0.25 g) with (0.05 g) amino group and aromatic aldehyde combinedly, then dissolved with (8 ml) of tetrahydrofuran (THF) at room temperature (300 K). The optical properties as absorption coefficient, reflectance, transmittance, skin depth, energy gap, refractive index, extinction coefficient, and urbach energy were studied. The transmittance value of the pure PVC film was 1.0 then declined gradually after dispersion with the compounds to the lowest value at 0.1, the reflectance also decreased. The energy gap for direct allowed decreased from (5.1 to 2.9 eV), and indirect transition decreased also from (5.0 to 2.8 eV), this behavior indicate that the modified films become work as semi-crystalline compounds toward the light. In tailoring, the optical properties, and urbach energy have been increased after mixed with PVC polymer. The scattering energy (Ed) and the effective single oscillator (Eo), were decreased. In a similar manner the dielectric constant high frequency (ε∞) and effective mass (Nm*), of dielectric constants were increased for PVC modified films. The PVC modified films are appropriate for anti-reflected coating while being good suitable in high refractive lenses and photovoltaic cells applications.