An Analytical Method to Quantify Silica Nanoparticles Accumulated on the Surface of Polymer Nanocomposites Exposed to UV Radiation

摘要

Three films containing different mass fractions (0 %, 5 % and 10 %) of silica (SiO_2) nanoparticles have been subjected to controlled degradation conditions at specified humidity, temperature, and ultraviolet (UV) radiation doses over a period of 59 days. The mass fraction of extracted nanosilica is measured by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Results show the presence of nanosilica on the films containing 5 % and 10 % nanosilica, regardless of the exposure conditions. However, after UV exposure for 59 days, the mass fraction of nanosilica in the extracted solutions increase by factors of 2.3 and 1.7 for the 5 % and 10 % nanosilica films, respectively. Measurement variability is lower for the 10 % nanosilica films, likely due to the larger mass of nanosilica that is released. Results of this study will assist in establishing a reliable and sensitive method for measuring the release rate of silica nanoparticles from UV-irradiated polymer nanocomposites.