2,2-Bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (4-BDAF), CAS number 69563-88-8, has two phenoxyanilines connected by a hexafluoroisopropane. 2,2-Bis[4-(4-aminophenoxy)phenyl]hexafluoropropane is commonly used for the synthesis of polyimides. The steric effect from the trifluoromethyl substituents reduces the intermolecular interaction and their electron withdrawing effect to minimize the electron delocalization of the benzene rings. These properties lead to low dielectric constant (1.51–2.42 at 100 kHz) and low dielectric loss (0.00698), making the polyimides promising materials for telecommunication applications. The high optical transparency of these polyimides is exploited for the substrates in solar cells achieving 16.1% powder conversion efficiency.
The polyetherimides derived from 4-BDAF are also used in capacitive energy storage application with discharge density at 3.6 J/cm3 and charge-discharge efficiency at 96.5%.