Effect of Temperature on Surface Degradation and Nanoparticle Release of Nano-SiO2 Epoxy Coatings under UV Radiation

C.-C. Tien, A.C.-H. Chang, B.H.-C. Liu, L.-P. Sung
National Cheng Kung University, US

Keywords: nanoparticle, polymer, degradation, nanocoating

Summary:

To investigate the mechanisms of polymer degradation, polymer matrix, epoxy, with the addition of nanosilica (SiO2), was chosen. In this study an outdoor environment was simulated in the NIST (Nation Institute of Standards and Technology) SPHERE (Simulated Photodegradation vis High Energy Radiation Exposure) chambers, which are able to provide stable ultraviolet (UV) radiation and control the exposure temperature and relative humidity. After UV degradation, changes in surface morphology and the nanoparticles coverage percentage of specimens were obtained by Atomic Force Microscopy (AFM) measurements. In addition, a rinsing system was used to simulate the rain after the UV radiation exposure, and the rinsing water with released particles were collected and analyzed by inductively-coupled plasma optical emission spectroscopy (ICP-OES). The same experiment procedure was adapted to four different temperatures during UV radiation exposure. Effect of temperature on surface degradation and nanoparticle release of nano-SiO2 epoxy coatings as a function of UV radiation dose will be reported.