writer：Junbin Liao, Youqun Chu, Jianli Wang*, Meiqing Zhou, Yiming Cao
keywords：copolymers，dielectric properties， films， glass transition， membranes
source：期刊
Issue time：2015年
A series of thermally stable poly(arylene ether ketone)s (PAEKs) bearing benzimidazole structure in the main chains, named poly(arylene ether ketone-benzimidazole)s (PAEK-BIs), were directly synthesized by polycondensation of dimethyl bisphenol, dibenzimidazole bisphenol, and difluorobenzophenones. By systematically varying the amount ratio of two kind of bisphenols, the content of benzimidazole moiety in the backbone was controlled straightforwardly. The prepared amorphous polymers were characterized in terms of Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, thermal, dielectric, and gas transport properties. Evaluation of solubility reveals that PAEK-BIs with >60% content of benzimidazole units could be soluble in commonly used organic solvents. Also polymers containing content-tunable benzimidazole show high glass-transition temperatures (T-g''s, 157-319 degrees C) and excellent thermal stability (e.g., temperature of 5% weight loss, above 438 degrees C in air). Dielectric constants of PAEK-BIs measured at 25 degrees C are all less than 2.66 in the frequency range of 0.1-50 kHz. For dense films, the ideal gas selectivity and permeability coefficients could be compared with that of commercial Ultem 1000 membrane, which indicate that the PAEK-BIs are potential to be used for gas separation membrane material. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41289.