Poly(arylene benzimidazole)s as novel high-performance polymers

Abstract

Series of novel poly(arylene benzimidazole)s (PABIs) was obtained by condensation polymerization of aromatic bifluorides with the monomers of di(benzimidazolyl)benzenes (synthesized by reaction of the isomeric phthalic acids with o-phenylenediamine) via a C–N coupling reaction. The structures of this series of polymers were characterized by Fourier transform infrared, proton nuclear magnetic resonance (1H NMR) spectroscopy and elemental analysis, and the results showed good agreement with the proposed structures. These synthesized polymers exhibited relatively high glass-transition temperatures (Tg>240 °C), good thermal stability with high decomposition temperatures (Td>450 °C) and excellent solubility in organic solvents. On the atomic scale, the molecular simulation results indicated that the PABI polymers exhibited a zigzag molecular chain structure with a high free volume fraction due to the different linkage modes of the monomers in the polymerization process. On the macro level, the PABI polymers possessed high tensile strength with good toughness; the mechanical behavior of the PABI polymers indicates that they can be considered a new class of high-performance polymers. Series of novel PABIs have been obtained by the condensation polymerization of aromatic bifluorides with di(benzimidazolyl)benzenes via a C–N coupling reaction. PABI exhibited zigzag molecular chain structure with a high free volume fraction, and they showed relatively high glass-transition temperatures (Tg>240), good thermal stability with high decomposition temperatures (Td>450) and excellent solubility in organic solvents. The mechanical behavior of the PABI polymers suggested that they can be considered as a new class of high-performance polymers.