High thermal stability and low dielectric constant of soluble polyimides containing asymmetric bulky pendant groups

Two new aromatic diamines with asymmetric structure: 3,5-bis(trifluoromethyl) phenyl-2,4-diaminobenzene (2a) and 3,5-dimethylphenyl-2,4-diaminobenzene (2b), were synthesized by a facile two-step re...