Encapsulation of flexible organic light emitting diodes by UV-cure epoxy siloxane

摘要

In this research, a silicon additive was synthesized by reaction of the hydroxyl terminated poly-dimethyl siloxane (PDMS-OH) with 3-glycidoxy propyl tri-methoxy silane (TMS-epoxy). The synthesized silicon additive characterized and evaluated to use as a curing agent for preparing high-performance and impermeable epoxy resin for encapsulation of flexible optoelectronic devices such as thin film photovoltaics and polymer light-emitting diodes to protect them against water penetration and increase their lifespan. The synthesized additive was characterized by FTIR, NMR, and elemental analysis. Thermal properties of the UV curable resin were investigated by using DSC and DMTA. The prepared UV cure epoxy resin exhibited an appropriate melting temperature (56.19 degrees C). Contact angle test, SEM, and calcium test was used to investigate the properties of UV-cured coating resin. The water contact angle of the cured prepared resin film showed good hydrophobicity. The SEM results confirmed the uniformity of cured film and UV cure resin dispersion. Transparency and flexibility of the cured film to encapsulate the flexible light emitting diodes are acceptable. The permeability of cured film to water vapor was evaluated by calcium test, which shows the cured film suitability to encapsulate the FOLED. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48033.