Composite polymeric films with photocatalytic properties

Polymeric films and in particular polypropylene (PP) films could be selected as excellent substrates for photocatalytic applications based on TiO2. However, hydrophobic surface of PP makes very difficult the adhesion of TiO2 particles on its surface. In this work corona pre-Treated PP was used as a support for commercial TiO2 in order to remove organic dye methylene blue (MB) from aqueous solution under UV irradiation. In details, the pre-Treated polypropylene PP films were coated with TiO2 particles by dip-coating technique. The corona pre-Treatment is a practical and effective method to increase the wettability of organic polymers due to the introduction of negative groups (COO-,-O-O-) onto the surfaces, which results in a better adhesion of the photocatalyst. The obtained coated films were characterized with different techniques sand the photocatalytic effect under UV light was analyzed in the degradation of MB dye. The photocatalytic tests were carried out in a batch photoreactor irradiated by a UV lamp (nominal power of 8 W and wavelength emission 365 nm). The experimental results showed that the coating of TiO2 onto PP films allowed to achieve a MB discoloration of 47% after about 180 min of UV irradiation. In contrast the unfunctionalized PP film did not shown any photocatalytic activity under the same irradiation conditions.