Intrinsically Stretchable Emissive Layer for Green and Red Phosphorescent OLEDs: Small Molecules Blended with SEBS Elastomer
Hyein Ha, Jaeseung Kim, Young Jae Shim, Aqsa Irfan, Ajay Nimbalkar, Ramachandran Elumalai, Thi Na Le, Hyunjung Kim, Min Chul Suh
Abstract
In the field of stretchable electronics, intrinsically stretchable organic light‐emitting diodes (IS‐OLEDs) are considered to be essential units. However, research on stretchable electroluminescent layers for light‐emitting devices is limited. The most common method to obtain an effective stretchable emitting layer is blending a conjugated polymer with an elastomer. In this study, blending small molecules with a thermoplastic styrene‐ethylene‐butylene‐styrene (SEBS) elastomer to fabricate a stretchable emitting layer is proposed. The mechanical, electrical, and morphological properties of the blended films are studied. The results show that the blended films can be stretched up to 200% without any morphological change such as cracking or particle shedding. Additionally, an OLED is fabricated with a stretchable electroluminescent layer and demonstrated its functionality.