Hole-transporting side-chain polystyrenes based on TCTA with tuned glass transition and optimized electronic properties

Limberg, F.R.P.; Miasojedovas, A.; Pingel, P.; Reisbeck, F.; Janietz, S.; Monkman, A.P.; Kruger, H.

Abstract

The development of crosslinkable materials for the fabrication of solution processable OLEDs presents challenges, especially regarding the adjustment of the glass transition (Tg), which has a significant influence on crosslinking kinetics and device life-time. Crosslinkable hole transport materials based on poly(N, N-bis(4-(9H-carbazol-9-yl)phenyl)-4-vinylaniline) (poly-TCTA) with covalently attached plasticizers for Tg control and azide functionalities for azide-alkyne crosslinking are presented. These polymers have an optimal T-g of around 150 degrees C and show superior crosslinking performances and solution resistibilities. Incorporation of electron-pushing alkoxides to the pendant groups combines the Tg adjustment approach with a systematic tuning of the HOMO level from -5.7 to -5.3 eV. All presented polymers have good charge transport and injection properties and are ideal for applications in phosphorescent OLEDs due to their high triplet energies (>2.8 eV). The new crosslinkable poly-TCTA-based materials are applied as hole-transport layers (HTLs) in fully solution-processed OLEDs. An improvement of the device performance is demonstrated for OLEDs with additional crosslinked HTL.

Citation

Limberg, F., Miasojedovas, A., Pingel, P., Reisbeck, F., Janietz, S., Monkman, A., & Kruger, H. (2015). Hole-transporting side-chain polystyrenes based on TCTA with tuned glass transition and optimized electronic properties. RSC Advances, 5(101), 83122-83128

• Journal Article Type: Article
• Publication Date: 2015
• Deposit Date: Jan 18, 2017
• Journal: RSC Advances
• Publisher: Royal Society of Chemistry
• Volume: 5
• Issue: 101
• Pages: 83122-83128
• Publisher URL: <Go to ISI>://WOS:000362438300060