Novel low‐dielectric‐constant fluorine‐functionalized polysulfone with outstanding comprehensive properties

Abstract

Abstract In this work, a series of fluorine‐functionalized polysulfone (F‐PSU) copolymers with intrinsic low dielectric constants (low ε ) are reported, which are derived from the polycondensation reaction of 4,4′‐dichlorophenyl sulfone with bisphenol A and bisphenol F (BPF) compounds. The resulting F‐PSU copolymers show high glass transition temperatures ( T g ) varying from 187 to 201 °C and are thermally stable up to 500 °C under an N 2 atmosphere. The introduction of BPF units into the PSU copolymers imparts enhanced hydrophobic properties to the F‐PSU films with increased water contact angle values from 66.2° to 93.7°. Moreover, the dielectric constant and dielectric loss of the F‐PSU (sample V) film are as low as 2.2 and 0.003 at 1 kHz, respectively. Interestingly, the dielectric properties are relatively stable to near the glass transition temperature, which is because of the existence of BPF structures in the molecular backbone. Furthermore, the F‐PSU copolymers are soluble in common solvents and can be readily fabricated into flexible transparent films by the spin casting method. © 2020 Society of Chemical Industry