Silica nanoparticle-embedded sol-gel organic/inorganic hybrid nanocomposite for transparent OLED encapsulation

Abstract

We report a transparent moisture barrier coating fabricated with a silica nanoparticle-embedded organic/inorganic hybrid (S-H) nanocomposite. We used a photo-curable, cyclo-aliphatic epoxy based hybrid material (hyrimer) as the matrix and a solvent-less, monodisperse silica nanoparticles as the reinforcement responsible for creating tortuous diffusive path for moisture penetrants. The S-H nanocomposite barrier coating exhibits a single layerWVTRof 0.24 g/m(2) day (Ca-test) and an optical transparency of 90% in the visible range. The performance of the barrier coating was also verified in an OLED lifetime measurement test, in which an OLED encapsulated with an S-H nanocomposite barrier coating showed significantly extended lifetime. (C) 2011 Elsevier B. V. All rights reserved.