Intrinsic low‐dielectric‐constant polyimides based on a novel diamine having −CF₃ groups and kinkable 1,4‐diisopropylbenzene units

Abstract

Polyimides (PIs) with low dielectric constants and optical transparency are of great interest in 5G/6G communication applications and in the microelectronics industry, where they are used as interlayer dielectric materials, wearable display devices and so forth. In this study, we designed and synthesized a novel fluorinated diamine called 4,4′‐(1,4‐phenylenebis(propane‐2,2‐diyl))diphenoxybis(2‐(trifluoromethyl)‐4‐aminobenzene) (BPBTAB) monomer from bisphenol‐P having diisopropyl benzene units and fabricated four novel BPBTAB‐X PIs. These PI films possess excellent properties such as a low dielectric constant (1.13–1.84 at 1 MHz), high 5% loss temperature (395–491 °C), moderate glass transition temperature (223–254 °C), good tensile modulus (0.827–1.076 GPa), excellent optical properties (T450 up to 83.37%), low moisture absorption (<0.63%) and good solubility in organic solvents. Hence, the as‐synthesized PI films exhibit excellent comprehensive properties for high‐frequency 5G/6G communication applications. © 2023 Society of Chemical Industry.