Development of transparent bacterial cellulose nanocomposite film as substrate for flexible organic light emitting diode (OLED) display

Nanocomposite film composed of bacterial cellulose (10-50 wt.%) and poly-urethane (PU) based resin was fabricated and utilized as a substrate for flexible organic light emitting diode (OLED) display. The performance of the nanocomposite satisfied the criteria for the substrate of OLED with an additional feature of flexibility. The visible light transmittance of the nanocomposite film was as high as 80%. Its thermal stability was stable up to 150 degrees C while its dimensional stability in terms of coefficient of thermal expansion (CTE) was less than 20 ppm/K. After OLED was fabricated on the substrate through thermal evaporation technique, the OLED performed highest current efficiency of 0.085 cd/A and power efficiency of 0.021 lm/W at 200 cd/m(2) while retained its flexible feature, suggesting that bacterial cellulose nanocomposite is a promising material for the development of substrate for flexible OLED display. (C) 2011 Elsevier B.V. All rights reserved.