The objective of this study is to investigate the role of ZnO nanoparticles in the life cycle of a waterborne polyurethane (PU) nanocomposite during UV exposure. The effects of loadings and sizes of ZnO nanoparticles on photodegradation of ZnO/PU films were evaluated. The chemical changes of the exposed specimens were examined by Fourier Transform Infrared Spectroscopy (FTIR). Changes in surface morphology were characterized by atomic force microscopy (AFM). The results clearly show that ZnO nanoparticles can act as a photo-catalyst or a photo-stabilizer, depending on the UV exposure conditions. The photoreactivity of the ZnO nanoparticles is affected by the nanoparticle properties (e.g., size and loading). It appears that the polymers in the vicinity of the nanoparticles would be preferentially degraded when the nanoparticles behave as a photo-catalyst, or protected when the nanoparticles behave as a photo-stabilizer.
Conference Dates: June 20-25, 2010
Conference Location: Anaheim, CA
Conference Title: Nanotech2010
Pub Type: Conferences
AFM, building technology, life cycle, nanoparticles, nanocomposites, UV exposure