Enhancement of barrier properties by wet coating of epoxy-ZrP nanocomposites on various inorganic layers

• Published in: Progress in organic coatings Vol. 108; pp. 25 - 29
• Main Authors: Kim, Haesook, Ra, Ha Na, Kim, Mansu, Kim, Hyun Gi, Kim, Sung Soo
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.07.2017; Elsevier BV
• Subjects: Atomic layer epitaxy; Atomic structure; Barrier properties; Coating; Dispersion; Encapsulation; Epoxy coatings; Epoxy nanocomposites; Nanocomposites; Optical properties; Organic light emitting diodes; Water vapor; Wet coating; Zirconium; α-zirconium phosphate; Barrier properties; α-zirconium phosphate; Wet coating; Epoxy nanocomposites
• ISSN: 0300-9440; 1873-331X
• DOI: 10.1016/j.porgcoat.2017.04.001

•Epoxy-ZrP nanocomposite coating layer was prepared on various inorganic layer.•The barrier properties were improved after epoxy-ZrP nanocomposite coating.•Organic-inorganic hybrid coating layers were applied to OLED encapsulation. Epoxy-ZrP (α-zirconium phosphate) nanocomposites were wet-coated on various inorganic layers to improve their barrier properties. Inorganic layers were deposited on a plastic substrate by sputtering or atomic layer deposition (ALD). The water vapor transmission rate (WVTR) of the inorganic layers varied from 10−1g/m2/day to 10−4g/m2/day. ZrP nanoplatelets were synthesized using a reflux method and were well dispersed to form an epoxy-ZrP solution for wet coating. TEM images confirmed that the ZrP nanoplatelets were well dispersed in the epoxy matrix. The coating solution was bar-coated on the inorganic layer and thermally cured. The WVTR dramatically decreased up to 92% after epoxy-ZrP nanocomposite coating on all choices of inorganic layer. The optical properties remained constant or in some cases decreased by about 4%. The optimal structure composed of inorganic and epoxy-ZrP nanocomposite layers was used in OLED encapsulation, resulting in an extended lifetime compared to OLEDs encapsulated with bare inorganic layers without a nanocomposite coating.