Functionalized Poly(phenylene ether) with high thermal stability as flexible dielectrics and substrates for organic field-effect transistors

Extensive research efforts are devoted into seeking the thermally and mechanically durable dielectric materials for flexible electronics. In this work, a series of sulfonylated poly (phenylene ether)s (PPEs) were synthesized and served as gate dielectrics in the flexible OFET devices with crosslinked poly (2-allyl-6-methylphenol-co-2,6dimethylphenol) (APPE) as substrate. The chemical structure, thermal, morphology, and dielectric properties were investigated, and the corresponding OFET devices were accordingly fabricated and characterized. We found that the discrepancy in sulfone content of PPE-xS renders the difference in thermal stability, surface polarity and dielectric constants. Among them, PPE-9kS with the highest sulfone content of 63% shows the best dielectric properties in the flexible OFET devices with hole mobility (mu p) of 0.45 cm2 V-1 s- 1, outperforming its parent polymer without sulfone group (PPE-9k) with mu p of 0.14 cm2 V-1 s- 1. Besides, the flexible device with PPE-9kS as dielectric exhibits highly retained device performance after cyclic bending or thermal treatment, which indicates the decent mechanical and thermal durability. The present study documents a practical methodology to fabricate a high-performance flexible OFET with excellent thermal and mechanical stability.

Automated summary

The research focuses on seeking durable dielectric materials for flexible electronics, with sulfonated PPEs showing promising results. Among them, PPE-9kS with the highest sulfone content of 63% exhibits the best dielectric properties in flexible OFET devices. With excellent mechanical and thermal stability, devices with PPE-9kS as dielectric show highly retained performance after cyclic bending or thermal treatment.