Surface Modification of Alumina Nano-Particles by UV-Induced Grafting Polymerization of 2-Hydroxyethyl Methacrylate
Alumina nano-particles was grafted with poly(2-hydroxyethyl methacrylate) (PHEMA) utilizing the sequential method; that is, the alumina surface was first rendered with initiator, benzophenone, by UV-irradiation followed by the grafting polymerization of HEMA on the surface which was initiated thermally and propagated via the free-radical polymerization. FT-IR spectroscopy confirmed the successful grafting of PHEMA onto the alumina surface. Determined by thermalgravimetry (TG), the amount of benzophenone on the alumina surface was found to increase with the UV-irradiation time; however upon grafting of PHEMA, the amount of grafted-PHEMA was the same irrespective of the reaction time. The glass transition temperature (Tg) of grafted-PHEMA on alumina particles was approximately 93 °C that is higher than that of PHEMA which has Tg around 85 °C. This indicates the more restricted movement of grafted-PHEMA compared with the ungrafted-PHEMA.
S. Suttiruengwong and W. Sricharussin
K. Yantaboot et al., "Surface Modification of Alumina Nano-Particles by UV-Induced Grafting Polymerization of 2-Hydroxyethyl Methacrylate", Advanced Materials Research, Vols. 93-94, pp. 95-98, 2010