Preparation and characterization of poly( l-lactic acid)/TiO 2 nanoparticle nanocomposite films with high transparency and efficient photodegradability

Abstract

Poly( l-lactic acid)–TiO 2 nanoparticle nanocomposite films were prepared by incorporating surface modified TiO 2 nanoparticles into polymer matrices. In the process of preparing the nanocomposite films, severe aggregation of TiO 2 nanoparticles could be reduced by surface modification by using carboxylic acid and long-chain alkyl amine. As a result, the nanocomposite films with high transparency, similar to pure PLA films, were obtained without depending on the amount of added TiO 2 nanoparticles. A TEM micrograph of the nanocomposite films suggests that the TiO 2 nanoparticles of 3–6 nm in diameter were uniformly dispersed in polymer matrices. Photodegradation of PLA–TiO 2 nanoparticle nanocomposite films was also investigated. The results showed that nanocomposite films could be efficiently photodegraded by UV irradiation in comparison with pure PLA.