Fluorene-Arylamine Copolymers: Separable Control of Hole Transport and Light Emission Through Composition and Conformation

Lambeva, N.T., Limbu, S., Kim, J.-S. and Bradley, D.D.C. (2025), Fluorene-Arylamine Copolymers: Separable Control of Hole Transport and Light Emission Through Composition and Conformation. J Polym Sci, 63: 2113-2121. https://doi.org/10.1002/pol.20250063

The goal of this study was to investigate how the composition and conformation of fluorene–arylamine copolymers can separately control hole transport and light emission, providing strategies for the design of multifunctional organic semiconductors.

Key findings revealed that hole mobility in these copolymers depends predominantly on chemical composition. Introducing a small percentage (5%) of arylamine units into polyfluorene drastically reduced mobility due to charge trapping. However, increasing the arylamine content restored and improved mobility via direct arylamine-to-arylamine hopping. Conversely, light emission properties were strongly influenced by polymer chain conformation (β-phase formation), but had minimal impact on hole transport. This demonstrates that charge transport and emission characteristics can be independently optimized within a single material.

Fluxim’s Paios platform was critical for measuring charge transport properties via Dark Injection Transient (DIT) techniques. Paios enabled precise evaluation of hole mobilities across different material compositions and conformations, providing reliable, reproducible data essential for correlating molecular design to device-relevant properties.

The findings are important as they offer valuable guidelines for tuning optoelectronic properties separately in polymer semiconductors—crucial for advancing high-efficiency OLEDs, flexible electronics, and next-generation photonic devices.